v6.0.2

See: https://github.com/ArthurSonzogni/FTXUI/pull/1021?notification_referrer_id=NT_kwDOAEieQrMxNTU3OTg4MDA1MDo0NzU5MTA2#discussion_r2019827970

.github/workflows/build.yaml

@@ -19,18 +19,16 @@ jobs:
           - name: Linux GCC
             os: ubuntu-latest
             compiler: gcc
-            gcov_executable: gcov
 
           - name: Linux Clang
             os: ubuntu-latest
             compiler: llvm
             gcov_executable: "llvm-cov gcov"
 
-          # https://github.com/aminya/setup-cpp/issues/246
-          #- name: MacOS clang
-            #os: macos-latest
-            #compiler: llvm
-            #gcov_executable: "llvm-cov gcov"
+          - name: MacOS clang
+            os: macos-latest
+            compiler: llvm
+            gcov_executable: "llvm-cov gcov"
 
           - name: Windows MSVC
             os: windows-latest
@@ -85,7 +83,7 @@ jobs:
           ctest -C Debug --rerun-failed --output-on-failure;
 
       - name: Unix - coverage
-        if: runner.os != 'Windows'
+        if: matrix.gcov_executable != ''
         working-directory: ./build
         run: >
           gcovr
@@ -220,6 +218,8 @@ jobs:
           rsync -amv
           --include='*/'
           --include='*.html'
+          --include='*.css'
+          --include='*.mjs'
           --include='*.js'
           --include='*.wasm'
           --exclude='*'

.github/workflows/codeql.yml

@@ -1,76 +0,0 @@
-# For most projects, this workflow file will not need changing; you simply need
-# to commit it to your repository.
-#
-# You may wish to alter this file to override the set of languages analyzed,
-# or to provide custom queries or build logic.
-#
-# ******** NOTE ********
-# We have attempted to detect the languages in your repository. Please check
-# the `language` matrix defined below to confirm you have the correct set of
-# supported CodeQL languages.
-#
-name: "CodeQL"
-
-on:
-  push:
-    branches: [ "main" ]
-  pull_request:
-    # The branches below must be a subset of the branches above
-    branches: [ "main" ]
-  schedule:
-    - cron: '45 22 * * 5'
-
-jobs:
-  analyze:
-    name: Analyze
-    runs-on: ${{ (matrix.language == 'swift' && 'macos-latest') || 'ubuntu-latest' }}
-    permissions:
-      actions: read
-      contents: read
-      security-events: write
-
-    strategy:
-      fail-fast: false
-      matrix:
-        language: [ 'cpp' ]
-        # CodeQL supports [ 'cpp', 'csharp', 'go', 'java', 'javascript', 'python', 'ruby' ]
-        # Use only 'java' to analyze code written in Java, Kotlin or both
-        # Use only 'javascript' to analyze code written in JavaScript, TypeScript or both
-        # Learn more about CodeQL language support at https://aka.ms/codeql-docs/language-support
-
-    steps:
-    - name: Checkout repository
-      uses: actions/checkout@v3
-
-    # Initializes the CodeQL tools for scanning.
-    - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
-      with:
-        languages: ${{ matrix.language }}
-        # If you wish to specify custom queries, you can do so here or in a config file.
-        # By default, queries listed here will override any specified in a config file.
-        # Prefix the list here with "+" to use these queries and those in the config file.
-
-        # For more details on CodeQL's query packs, refer to: https://docs.github.com/en/code-security/code-scanning/automatically-scanning-your-code-for-vulnerabilities-and-errors/configuring-code-scanning#using-queries-in-ql-packs
-        # queries: security-extended,security-and-quality
-
-
-    # Autobuild attempts to build any compiled languages  (C/C++, C#, Go, or Java).
-    # If this step fails, then you should remove it and run the build manually (see below)
-    - name: Autobuild
-      uses: github/codeql-action/autobuild@v2
-
-    # ℹ️ Command-line programs to run using the OS shell.
-    # 📚 See https://docs.github.com/en/actions/using-workflows/workflow-syntax-for-github-actions#jobsjob_idstepsrun
-
-    #   If the Autobuild fails above, remove it and uncomment the following three lines.
-    #   modify them (or add more) to build your code if your project, please refer to the EXAMPLE below for guidance.
-
-    # - run: |
-    #     echo "Run, Build Application using script"
-    #     ./location_of_script_within_repo/buildscript.sh
-
-    - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
-      with:
-        category: "/language:${{matrix.language}}"

.gitignore

@@ -38,14 +38,16 @@ out/
 !doc/**/*.md
 
 # examples directory:
-!examples/**/*.txt
 !examples/**/*.cpp
+!examples/**/*.css
 !examples/**/*.hpp
-!examples/**/*.ipp
 !examples/**/*.html
-!examples/**/*.py
-!examples/**/*.js
 !examples/**/*.html.disabled
+!examples/**/*.ipp
+!examples/**/*.js
+!examples/**/*.mjs
+!examples/**/*.py
+!examples/**/*.txt
 
 # include directory:
 !include/ftxui/**/*.hpp

CHANGELOG.md

@@ -1,8 +1,26 @@
 Changelog
 =========
 
-current (development) 
----------------------
+6.0.2 (2025-03-30)
+-----
+
+### Component
+- BugFix: Fix major crash on Windows affecting all components. See #1020
+- BugFix: Fix focusRelative.
+
+6.0.1 (2025-03-28)
+-----
+
+Same as v6.0.0.
+
+Due to a problem tag v6.0.0 was replaced. This isn't a good practice and affect
+developers that started using it in the short timeframe. Submitting a new
+release with the same content is the best way to fix this.
+
+See #1017 and #1019.
+
+6.0.0 (2025-03-23)
+-----
 
 ### Component
 - Feature: Add support for raw input. Allowing more keys to be detected.
@@ -16,6 +34,9 @@ current (development)
 - Feature: Add support for `Input`'s insert mode. Add `InputOption::insert`
   option. Added by @mingsheng13.
 - Feature: Add `DropdownOption` to configure the dropdown. See #826.
+- Feature: Add support for Selection. Thanks @clement-roblot. See #926.
+  - See `ScreenInteractive::GetSelection()`.
+  - See `ScreenInteractive::SelectionChange(...)` listener.
 - Bugfix/Breaking change: `Mouse transition`:
   - Detect when the mouse move, as opposed to being pressed.
     The Mouse::Moved motion was added.
@@ -35,16 +56,43 @@ current (development)
 - Bugfix: Fix cursor position in when in the last column. See #831.
 - Bugfix: Fix `ResizeableSplit` keyboard navigation. Fixed by #842.
 - Bugfix: Fix `Menu` focus. See #841
+- Feature: Add `ComponentBase::Index()`. This allows to get the index of a
+  component in its parent. See #932
+- Feature: Add `EntryState::index`. This allows to get the index of a menu entry.
+  See #932
 - Feature: Add `SliderOption::on_change`. This allows to set a callback when the
   slider value changes. See #938.
+- Bugfix: Handle `Dropdown` with no entries.
+- Bugfix: Fix crash in `LinearGradient` due to float precision and an off-by-one
+          mistake. See #998.
 
 ### Dom
+- Feature: Add `italic` decorator. For instance:
+  ```cpp
+  auto italic_text = text("Italic text") | italic;
+  ```
+  ```cpp
+  auto italic_text = italic(text("Italic text"));
+  ```
+  Proposed by @kenReneris in #1009.
 - Feature: Add `hscroll_indicator`. It display an horizontal indicator
   reflecting the current scroll position. Proposed by @ibrahimnasson in
   [issue 752](https://github.com/ArthurSonzogni/FTXUI/issues/752)
 - Feature: Add `extend_beyond_screen` option to `Dimension::Fit(..)`, allowing
   the element to be larger than the screen. Proposed by @LordWhiro. See #572 and
   #949.
+- Feature: Add support for Selection. Thanks @clement-roblot. See #926.
+  - See `selectionColor` decorator.
+  - See `selectionBackgroundColor` decorator.
+  - See `selectionForegroundColor` decorator.
+  - See `selectionStyle(style)` decorator.
+  - See `selectionStyleReset` decorator.
+- Breaking change: Change how "focus"/"select" are handled. This fixes the
+  behavior.
+- Breaking change: `Component::OnRender()` becomes the method to override to
+  render a component. This replaces `Component::Render()` that is still in use
+  to call the rendering method on the children. This change allows to fix a
+  couple of issues around focus handling.
 
 ### Screen
 - Feature: Add `Box::IsEmpty()`.

CMakeLists.txt

@@ -2,7 +2,7 @@ cmake_minimum_required(VERSION 3.12)
 
 project(ftxui
   LANGUAGES CXX
-  VERSION 5.0.0
+  VERSION 6.0.2
   DESCRIPTION "C++ Functional Terminal User Interface."
 )
 
@@ -56,11 +56,12 @@ add_library(dom
   include/ftxui/dom/flexbox_config.hpp
   include/ftxui/dom/node.hpp
   include/ftxui/dom/requirement.hpp
+  include/ftxui/dom/selection.hpp
   include/ftxui/dom/take_any_args.hpp
   src/ftxui/dom/automerge.cpp
+  src/ftxui/dom/selection_style.cpp
   src/ftxui/dom/blink.cpp
   src/ftxui/dom/bold.cpp
-  src/ftxui/dom/hyperlink.cpp
   src/ftxui/dom/border.cpp
   src/ftxui/dom/box_helper.cpp
   src/ftxui/dom/box_helper.hpp
@@ -81,13 +82,16 @@ add_library(dom
   src/ftxui/dom/graph.cpp
   src/ftxui/dom/gridbox.cpp
   src/ftxui/dom/hbox.cpp
+  src/ftxui/dom/hyperlink.cpp
   src/ftxui/dom/inverted.cpp
+  src/ftxui/dom/italic.cpp
   src/ftxui/dom/linear_gradient.cpp
   src/ftxui/dom/node.cpp
   src/ftxui/dom/node_decorator.cpp
   src/ftxui/dom/paragraph.cpp
   src/ftxui/dom/reflect.cpp
   src/ftxui/dom/scroll_indicator.cpp
+  src/ftxui/dom/selection.cpp
   src/ftxui/dom/separator.cpp
   src/ftxui/dom/size.cpp
   src/ftxui/dom/spinner.cpp

README.md

@@ -43,7 +43,7 @@ A simple cross-platform C++ library for terminal based user interfaces!
  * **Cross platform**: Linux/MacOS (main target), WebAssembly, Windows (Thanks to contributors!).
  * Learn by [examples](#documentation), and [tutorials](#documentation)
  * Multiple packages: CMake [FetchContent]([https://bewagner.net/programming/2020/05/02/cmake-fetchcontent/](https://cmake.org/cmake/help/latest/module/FetchContent.html)) (preferred), vcpkg, pkgbuild, conan.
- * Good practises: documentation, tests, fuzzers, performance tests, automated CI, automated packaging, etc...
+ * Good practices: documentation, tests, fuzzers, performance tests, automated CI, automated packaging, etc...
 
 ## Documentation
 
@@ -73,7 +73,7 @@ A simple cross-platform C++ library for terminal based user interfaces!
 
 #### DOM
 
-This module defines a hierarchical set of Element. An element manages layout and can be responsive to the terminal dimensions.
+This module defines a hierarchical set of Element. An Element manages layout and can be responsive to the terminal dimensions.
 
 They are declared in [<ftxui/dom/elements.hpp>](https://arthursonzogni.github.io/FTXUI/elements_8hpp_source.html
 )
@@ -109,6 +109,7 @@ Element can become flexible using the the `flex` decorator.
 
 An element can be decorated using the functions:
   - `bold`
+  - `italic`
   - `dim`
   - `inverted`
   - `underlined`
@@ -199,7 +200,7 @@ Complex [examples](https://github.com/ArthurSonzogni/FTXUI/blob/master/examples/
 
 #### Component
 
-The ftxui/component is needed when you want to produce dynamic UI, reactive to the user's input. It defines a set of ftxui::Component. A component reacts to Events (keyboard, mouse, resize, ...) and Render Element (see previous section).
+ftxui/component produces dynamic UI, reactive to the user's input. It defines a set of ftxui::Component. A component reacts to Events (keyboard, mouse, resize, ...) and Renders as an Element (see previous section).
 
 Prebuilt components are declared in [<ftxui/component/component.hpp>](https://arthursonzogni.github.io/FTXUI/component_8hpp_source.html)
 
@@ -293,7 +294,10 @@ Prebuilt components are declared in [<ftxui/component/component.hpp>](https://ar
 </details>
 
 ## Libraries for FTXUI
-- *Want to share a useful component using FTXUI? Feel free adding yours here*
+- *Want to share a useful Component for FTXUI? Feel free to add yours here*
+- [ftxui-grid-container](https://github.com/mingsheng13/grid-container-ftxui)
+- [ftxui-ip-input](https://github.com/mingsheng13/ip-input-ftxui)
+- [ftxui-image-view](https://github.com/ljrrjl/ftxui-image-view.git): For Image Display.
 
 
 ## Project using FTXUI
@@ -301,12 +305,12 @@ Prebuilt components are declared in [<ftxui/component/component.hpp>](https://ar
 Feel free to add your projects here:
 - [json-tui](https://github.com/ArthurSonzogni/json-tui)
 - [git-tui](https://github.com/ArthurSonzogni/git-tui)
+- [ostree-tui](https://github.com/AP-Sensing/ostree-tui)
 - [rgb-tui](https://github.com/ArthurSonzogni/rgb-tui)
 - [chrome-log-beautifier](https://github.com/ArthurSonzogni/chrome-log-beautifier)
 - [x86-64 CPU Architecture Simulation](https://github.com/AnisBdz/CPU)
 - [ltuiny](https://github.com/adrianoviana87/ltuiny)
 - [i3-termdialogs](https://github.com/mibli/i3-termdialogs)
-- [Just-Fast](https://github.com/GiuseppeCesarano/just-fast)
 - [simpPRU](https://github.com/VedantParanjape/simpPRU)
 - [Pigeon ROS TUI](https://github.com/PigeonSensei/Pigeon_ros_tui)
 - [hastur](https://github.com/robinlinden/hastur)
@@ -323,6 +327,27 @@ Feel free to add your projects here:
 - [eCAL monitor](https://github.com/eclipse-ecal/ecal)
 - [Path Finder](https://github.com/Ruebled/Path_Finder)
 - [rw-tui](https://github.com/LeeKyuHyuk/rw-tui)
+- [resource-monitor](https://github.com/catalincd/resource-monitor)
+- [ftxuiFileReader](https://github.com/J0sephDavis/ftxuiFileReader)
+- [ftxui_CPUMeter](https://github.com/tzzzzzzzx/ftxui_CPUMeter)
+- [Captain's log](https://github.com/nikoladucak/caps-log)
+- [FTowerX](https://github.com/MhmRhm/FTowerX)
+- [Caravan](https://github.com/r3w0p/caravan)
+- [Step-Writer](https://github.com/BrianAnakPintar/step-writer)
+- [XJ music](https://github.com/xjmusic/xjmusic)
+- [UDP chat](https://github.com/Sergeydigl3/udp-chat-tui)
+- [2048-cpp](https://github.com/Chessom/2048-cpp)
+- [Memory game](https://github.com/mikolajlubiak/memory)
+- [Terminal Animation](https://github.com/mikolajlubiak/terminal_animation)
+- [pciex](https://github.com/s0nx/pciex)
+- [Fallout terminal hacking](https://github.com/gshigin/yet-another-fallout-terminal-hacking-game)
+- [Lazylist](https://github.com/zhuyongqi9/lazylist)
+- [TUISIC](https://github.com/Dark-Kernel/tuisic)
+- [inLimbo](https://github.com/nots1dd/inLimbo)
+- [BestEdrOfTheMarket](https://github.com/Xacone/BestEdrOfTheMarket)
+- [terminal-rain](https://github.com/Oakamoore/terminal-rain)
+- [keywords](https://github.com/Oakamoore/keywords) ([Play web version :heart:](https://oakamoore.itch.io/keywords))
+- [FTB - tertminal file browser](https://github.com/Cyxuan0311/FTB)
 
 ### [cpp-best-practices/game_jam](https://github.com/cpp-best-practices/game_jam)
 
@@ -339,16 +364,15 @@ Several games using the FTXUI have been made during the Game Jam:
 - [smoothlife](https://github.com/cpp-best-practices/game_jam/blob/main/Jam1_April_2022/smoothlife.md)
 - [Consu](https://github.com/cpp-best-practices/game_jam/blob/main/Jam1_April_2022/consu.md)
 
-## External package
+## Utilization
 
-It is **highly** recommended to use CMake FetchContent to depend on FTXUI. This
-way you can specify which commit you would like to depend on.
+It is **highly** recommended to use CMake FetchContent to depend on FTXUI so you may specify which commit you would like to depend on.
 ```cmake
 include(FetchContent)
 
 FetchContent_Declare(ftxui
   GIT_REPOSITORY https://github.com/ArthurSonzogni/ftxui
-  GIT_TAG v3.0.0
+  GIT_TAG v6.0.2
 )
 
 FetchContent_GetProperties(ftxui)
@@ -358,13 +382,20 @@ if(NOT ftxui_POPULATED)
 endif()
 ```
 
-If you don't, the following packages have been created:
+If you don't, FTXUI may be used from the following packages:
 - [vcpkg](https://vcpkgx.com/details.html?package=ftxui)
 - [Arch Linux PKGBUILD](https://aur.archlinux.org/packages/ftxui-git/).
 - [conan.io](https://conan.io/center/ftxui)
 - [openSUSE](https://build.opensuse.org/package/show/devel:libraries:c_c++/ftxui)
+- 
+[![Packaging status](https://repology.org/badge/vertical-allrepos/libftxui.svg)](https://repology.org/project/libftxui/versions)
+
+If you choose to build and link FTXUI yourself, `ftxui-component` must be first in the linking order relative to the other FTXUI libraries, i.e.
+```bash
+g++ . . . -lftxui-component -lftxui-dom -lftxui-screen . . .
+```
+
 
-[![Packaging status](https://repology.org/badge/vertical-allrepos/ftxui.svg)](https://repology.org/project/ftxui/versions)
 
 ## Contributors
 

cmake/ftxui_set_options.cmake

@@ -83,10 +83,6 @@ function(ftxui_set_options library)
       target_compile_options(${library} PRIVATE "-Wpedantic")
       target_compile_options(${library} PRIVATE "-Wshadow")
       target_compile_options(${library} PRIVATE "-Wunused")
-      
-      if (CMAKE_CXX_COMPILER_ID STREQUAL "GNU")
-        target_compile_options(${library} PRIVATE "-Wuseless-cast")
-      endif()
     endif()
   endif()
 

cmake/ftxui_test.cmake

@@ -13,6 +13,7 @@ add_executable(ftxui-tests
   src/ftxui/component/component_test.cpp
   src/ftxui/component/component_test.cpp
   src/ftxui/component/container_test.cpp
+  src/ftxui/component/dropdown_test.cpp
   src/ftxui/component/hoverable_test.cpp
   src/ftxui/component/input_test.cpp
   src/ftxui/component/menu_test.cpp
@@ -38,8 +39,10 @@ add_executable(ftxui-tests
   src/ftxui/dom/gridbox_test.cpp
   src/ftxui/dom/hbox_test.cpp
   src/ftxui/dom/hyperlink_test.cpp
+  src/ftxui/dom/italic_test.cpp
   src/ftxui/dom/linear_gradient_test.cpp
   src/ftxui/dom/scroll_indicator_test.cpp
+  src/ftxui/dom/selection_test.cpp
   src/ftxui/dom/separator_test.cpp
   src/ftxui/dom/spinner_test.cpp
   src/ftxui/dom/table_test.cpp

doc/mainpage.md

@@ -50,42 +50,17 @@ int main(void) {
 └────┘└────────────────────────────────────┘└─────┘
 ```
 
-# Build {#build}
+## Configure {#configure}
+### Using CMake and find_package {#build-cmake-find-package}
 
-## Using CMake {#build-cmake}
+Assuming FTXUI is available or installed on the system.
 
-This is an example configuration for your **CMakeLists.txt**
-
-CMakeLists.txt
+**CMakeLists.txt**
 ```cmake
 cmake_minimum_required (VERSION 3.11)
-
-# --- Fetch FTXUI --------------------------------------------------------------
-include(FetchContent)
-
-set(FETCHCONTENT_UPDATES_DISCONNECTED TRUE)
-FetchContent_Declare(ftxui
-  GIT_REPOSITORY https://github.com/ArthurSonzogni/ftxui
-  # Important: Specify a GIT_TAG XXXXX here.
-  GIT_TAG main
-)
-
-FetchContent_GetProperties(ftxui)
-if(NOT ftxui_POPULATED)
-  FetchContent_Populate(ftxui)
-  add_subdirectory(${ftxui_SOURCE_DIR} ${ftxui_BINARY_DIR} EXCLUDE_FROM_ALL)
-endif()
-
-# ------------------------------------------------------------------------------
-
-project(ftxui-starter
-  LANGUAGES CXX
-  VERSION 1.0.0
-)
-
+find_package(ftxui 5 REQUIRED)
+project(ftxui-starter LANGUAGES CXX VERSION 1.0.0)
 add_executable(ftxui-starter src/main.cpp)
-target_include_directories(ftxui-starter PRIVATE src)
-
 target_link_libraries(ftxui-starter
   PRIVATE ftxui::screen
   PRIVATE ftxui::dom
@@ -94,7 +69,33 @@ target_link_libraries(ftxui-starter
 
 ```
 
-Subsequently, you build the project in the standard fashion as follows:
+### Using CMake and FetchContent {#build-cmake}
+
+If you want to fetch FTXUI using cmake:
+
+**CMakeLists.txt**
+```cmake
+cmake_minimum_required (VERSION 3.11)
+
+include(FetchContent)
+set(FETCHCONTENT_UPDATES_DISCONNECTED TRUE)
+FetchContent_Declare(ftxui
+  GIT_REPOSITORY https://github.com/ArthurSonzogni/ftxui
+  GIT_TAG main # Important: Specify a version or a commit hash here.
+)
+FetchContent_MakeAvailable(ftxui)
+
+project(ftxui-starter LANGUAGES CXX VERSION 1.0.0)
+add_executable(ftxui-starter src/main.cpp)
+target_link_libraries(ftxui-starter
+  PRIVATE ftxui::screen
+  PRIVATE ftxui::dom
+  PRIVATE ftxui::component # Not needed for this example.
+)
+```
+
+## Build
+
 ```bash
 mkdir build && cd build
 cmake ..
@@ -122,8 +123,8 @@ The project is comprised of 3 modules:
 
 This is the visual element of the program. It defines a `ftxui::Screen`, which
 is a grid of `ftxui::Pixel`. A Pixel represents a Unicode character and its
-associated style (bold, colors, etc.). The screen can be printed as a string
-using `ftxui::Screen::ToString()`. The following example highlights this
+associated style (bold, italic, colors, etc.). The screen can be printed as a
+string using `ftxui::Screen::ToString()`. The following example highlights this
 process:
 
 ```cpp
@@ -475,10 +476,11 @@ See [demo](https://arthursonzogni.github.io/FTXUI/examples/?file=component/linea
 
 ## Style {#dom-style}
 In addition to colored text and colored backgrounds. Many terminals support text
-effects such as: `bold`, `dim`, `underlined`, `inverted`, `blink`.
+effects such as: `bold`, `italic`, `dim`, `underlined`, `inverted`, `blink`.
 
 ```cpp
 Element bold(Element);
+Element italic(Element);
 Element dim(Element);
 Element inverted(Element);
 Element underlined(Element);
@@ -634,6 +636,26 @@ Produced by: `ftxui::Input()` from "ftxui/component/component.hpp"
 <script id="asciicast-223719" src="https://asciinema.org/a/223719.js" async></script>
 @endhtmlonly
 
+### Filtered input
+
+On can filter out the characters received by the input component, using
+`ftxui::CatchEvent`.
+
+```cpp
+std::string phone_number;
+Component input = Input(&phone_number, "phone number");
+
+// Filter out non-digit characters.
+input |= CatchEvent([&](Event event) {
+  return event.is_character() && !std::isdigit(event.character()[0]);
+});
+
+// Filter out characters past the 10th one.
+input |= CatchEvent([&](Event event) {
+  return event.is_character() && phone_number.size() >= 10;
+});
+```
+
 ## Menu {#component-menu}
 
 Defines a menu object. It contains a list of entries, one of them is selected.

examples/CMakeLists.txt

@@ -21,6 +21,8 @@ if (EMSCRIPTEN)
   get_property(EXAMPLES GLOBAL PROPERTY FTXUI::EXAMPLES)
   foreach(file
       "index.html"
+      "index.mjs"
+      "index.css"
       "sw.js"
       "run_webassembly.py")
     configure_file(${file} ${file})

examples/component/CMakeLists.txt

@@ -18,6 +18,7 @@ example(focus_cursor)
 example(gallery)
 example(homescreen)
 example(input)
+example(input_in_frame)
 example(input_style)
 example(linear_gradient_gallery)
 example(maybe)
@@ -38,6 +39,8 @@ example(radiobox)
 example(radiobox_in_frame)
 example(renderer)
 example(resizable_split)
+example(scrollbar)
+example(selection)
 example(slider)
 example(slider_direction)
 example(slider_rgb)

examples/component/button.cpp

@@ -1,66 +1,9 @@
-// Copyright 2020 Arthur Sonzogni. All rights reserved.
-// Use of this source code is governed by the MIT license that can be found in
-// the LICENSE file.
-#include <memory>  // for shared_ptr, __shared_ptr_access
-#include <string>  // for operator+, to_string
+#include "ftxui/component/component.hpp"
+#include "ftxui/component/screen_interactive.hpp"
 
-#include "ftxui/component/captured_mouse.hpp"  // for ftxui
-#include "ftxui/component/component.hpp"  // for Button, Horizontal, Renderer
-#include "ftxui/component/component_base.hpp"      // for ComponentBase
-#include "ftxui/component/screen_interactive.hpp"  // for ScreenInteractive
-#include "ftxui/dom/elements.hpp"  // for separator, gauge, text, Element, operator|, vbox, border
-
-using namespace ftxui;
-
-// This is a helper function to create a button with a custom style.
-// The style is defined by a lambda function that takes an EntryState and
-// returns an Element.
-// We are using `center` to center the text inside the button, then `border` to
-// add a border around the button, and finally `flex` to make the button fill
-// the available space.
-ButtonOption Style() {
-  auto option = ButtonOption::Animated();
-  option.transform = [](const EntryState& s) {
-    auto element = text(s.label);
-    if (s.focused) {
-      element |= bold;
-    }
-    return element | center | borderEmpty | flex;
-  };
-  return option;
-}
-
-int main() {
-  int value = 50;
-
-  // clang-format off
-  auto btn_dec_01 = Button("-1", [&] { value += 1; }, Style());
-  auto btn_inc_01 = Button("+1", [&] { value -= 1; }, Style());
-  auto btn_dec_10 = Button("-10", [&] { value -= 10; }, Style());
-  auto btn_inc_10 = Button("+10", [&] { value += 10; }, Style());
-  // clang-format on
-
-  // The tree of components. This defines how to navigate using the keyboard.
-  // The selected `row` is shared to get a grid layout.
-  int row = 0;
-  auto buttons = Container::Vertical({
-      Container::Horizontal({btn_dec_01, btn_inc_01}, &row) | flex,
-      Container::Horizontal({btn_dec_10, btn_inc_10}, &row) | flex,
-  });
-
-  // Modify the way to render them on screen:
-  auto component = Renderer(buttons, [&] {
-    return vbox({
-               text("value = " + std::to_string(value)),
-               separator(),
-               gauge(value * 0.01f),
-               separator(),
-               buttons->Render(),
-           }) |
-           border;
-  });
-
-  auto screen = ScreenInteractive::FitComponent();
-  screen.Loop(component);
-  return 0;
+int main(){
+    auto screen = ftxui::ScreenInteractive::Fullscreen();
+    auto testComponent = ftxui::Renderer([](){return ftxui::text("test Component");});
+    screen.Loop(testComponent);
+    return 0;
 }

examples/component/checkbox.cpp

@@ -1,30 +1,38 @@
 // Copyright 2021 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.
-#include <memory>  // for allocator, __shared_ptr_access
-#include <string>  // for string, basic_string, operator+, to_string
-#include <vector>  // for vector
+#include <array>  // for array
+#include <iostream>
+#include <memory>  // for shared_ptr, __shared_ptr_access
+#include <string>  // for operator+, to_string
 
 #include "ftxui/component/captured_mouse.hpp"  // for ftxui
-#include "ftxui/component/component.hpp"       // for Input, Renderer, Vertical
-#include "ftxui/component/component_base.hpp"  // for ComponentBase
-#include "ftxui/component/screen_interactive.hpp"  // for Component, ScreenInteractive
+#include "ftxui/component/component.hpp"  // for Checkbox, Renderer, Vertical
+#include "ftxui/component/component_base.hpp"      // for ComponentBase
+#include "ftxui/component/screen_interactive.hpp"  // for ScreenInteractive
 #include "ftxui/dom/elements.hpp"  // for operator|, Element, size, border, frame, vscroll_indicator, HEIGHT, LESS_THAN
 
+using namespace ftxui;
+
 int main() {
-  using namespace ftxui;
+  bool download = false;
+  bool upload = false;
+  bool ping = false;
 
-  Component input_list = Container::Vertical({});
-  std::vector<std::string> items(100, "");
-  for (size_t i = 0; i < items.size(); ++i) {
-    input_list->Add(Input(&(items[i]), "placeholder " + std::to_string(i)));
-  }
-
-  auto renderer = Renderer(input_list, [&] {
-    return input_list->Render() | vscroll_indicator | frame | border |
-           size(HEIGHT, LESS_THAN, 10);
+  auto container = Container::Vertical({
+      Checkbox("Download", &download),
+      Checkbox("Upload", &upload),
+      Checkbox("Ping", &ping),
   });
 
-  auto screen = ScreenInteractive::TerminalOutput();
-  screen.Loop(renderer);
+  auto screen = ScreenInteractive::FitComponent();
+  screen.Loop(container);
+
+  std::cout << "---" << std::endl;
+  std::cout << "Download: " << download << std::endl;
+  std::cout << "Upload: " << upload << std::endl;
+  std::cout << "Ping: " << ping << std::endl;
+  std::cout << "---" << std::endl;
+
+  return 0;
 }

examples/component/gallery.cpp

@@ -97,7 +97,25 @@ int main() {
   });
   sliders = Wrap("Slider", sliders);
 
-  // -- Layout -----------------------------------------------------------------
+  // A large text:
+  auto lorel_ipsum = Renderer([] {
+    return vbox({
+        text("Lorem ipsum dolor sit amet, consectetur adipiscing elit. "),
+        text("Sed do eiusmod tempor incididunt ut labore et dolore magna "
+             "aliqua. "),
+        text("Ut enim ad minim veniam, quis nostrud exercitation ullamco "
+             "laboris nisi ut aliquip ex ea commodo consequat. "),
+        text("Duis aute irure dolor in reprehenderit in voluptate velit esse "
+             "cillum dolore eu fugiat nulla pariatur. "),
+        text("Excepteur sint occaecat cupidatat non proident, sunt in culpa "
+             "qui officia deserunt mollit anim id est laborum. "),
+
+    });
+  });
+  lorel_ipsum = Wrap("Lorel Ipsum", lorel_ipsum);
+
+  // -- Layout
+  // -----------------------------------------------------------------
   auto layout = Container::Vertical({
       menu,
       toggle,
@@ -106,6 +124,7 @@ int main() {
       input,
       sliders,
       button,
+      lorel_ipsum,
   });
 
   auto component = Renderer(layout, [&] {
@@ -123,6 +142,8 @@ int main() {
                sliders->Render(),
                separator(),
                button->Render(),
+               separator(),
+               lorel_ipsum->Render(),
            }) |
            xflex | size(WIDTH, GREATER_THAN, 40) | border;
   });

examples/component/homescreen.cpp

@@ -424,7 +424,7 @@ int main() {
   auto paragraph_renderer_left = Renderer([&] {
     std::string str =
         "Lorem Ipsum is simply dummy text of the printing and typesetting "
-        "industry. Lorem Ipsum has been the industry's standard dummy text "
+        "industry.\nLorem Ipsum has been the industry's standard dummy text "
         "ever since the 1500s, when an unknown printer took a galley of type "
         "and scrambled it to make a type specimen book.";
     return vbox({
@@ -504,7 +504,10 @@ int main() {
   auto main_renderer = Renderer(main_container, [&] {
     return vbox({
         text("FTXUI Demo") | bold | hcenter,
-        tab_selection->Render(),
+        hbox({
+            tab_selection->Render() | flex,
+            exit_button->Render(),
+        }),
         tab_content->Render() | flex,
     });
   });

examples/component/input.cpp

@@ -15,30 +15,50 @@
 int main() {
   using namespace ftxui;
 
+  // The data:
   std::string first_name;
   std::string last_name;
   std::string password;
+  std::string phoneNumber;
 
+  // The basic input components:
   Component input_first_name = Input(&first_name, "first name");
   Component input_last_name = Input(&last_name, "last name");
 
+  // The password input component:
   InputOption password_option;
   password_option.password = true;
   Component input_password = Input(&password, "password", password_option);
 
+  // The phone number input component:
+  // We are using `CatchEvent` to filter out non-digit characters.
+  Component input_phone_number = Input(&phoneNumber, "phone number");
+  input_phone_number |= CatchEvent([&](Event event) {
+    return event.is_character() && !std::isdigit(event.character()[0]);
+  });
+  input_phone_number |= CatchEvent([&](Event event) {
+    return event.is_character() && phoneNumber.size() > 10;
+  });
+
+  // The component tree:
   auto component = Container::Vertical({
       input_first_name,
       input_last_name,
       input_password,
+      input_phone_number,
   });
 
+  // Tweak how the component tree is rendered:
   auto renderer = Renderer(component, [&] {
     return vbox({
-               text("Hello " + first_name + " " + last_name),
-               separator(),
                hbox(text(" First name : "), input_first_name->Render()),
                hbox(text(" Last name  : "), input_last_name->Render()),
                hbox(text(" Password   : "), input_password->Render()),
+               hbox(text(" Phone num  : "), input_phone_number->Render()),
+               separator(),
+               text("Hello " + first_name + " " + last_name),
+               text("Your password is " + password),
+               text("Your phone number is " + phoneNumber),
            }) |
            border;
   });

examples/component/input_in_frame.cpp

@@ -0,0 +1,30 @@
+// Copyright 2021 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <memory>  // for allocator, __shared_ptr_access
+#include <string>  // for string, basic_string, operator+, to_string
+#include <vector>  // for vector
+
+#include "ftxui/component/captured_mouse.hpp"  // for ftxui
+#include "ftxui/component/component.hpp"       // for Input, Renderer, Vertical
+#include "ftxui/component/component_base.hpp"  // for ComponentBase
+#include "ftxui/component/screen_interactive.hpp"  // for Component, ScreenInteractive
+#include "ftxui/dom/elements.hpp"  // for operator|, Element, size, border, frame, vscroll_indicator, HEIGHT, LESS_THAN
+
+int main() {
+  using namespace ftxui;
+
+  Component input_list = Container::Vertical({});
+  std::vector<std::string> items(100, "");
+  for (size_t i = 0; i < items.size(); ++i) {
+    input_list->Add(Input(&(items[i]), "placeholder " + std::to_string(i)));
+  }
+
+  auto renderer = Renderer(input_list, [&] {
+    return input_list->Render() | vscroll_indicator | frame | border |
+           size(HEIGHT, LESS_THAN, 10);
+  });
+
+  auto screen = ScreenInteractive::TerminalOutput();
+  screen.Loop(renderer);
+}

examples/component/scrollbar.cpp

@@ -0,0 +1,112 @@
+// Copyright 2023 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <ftxui/component/component.hpp>
+#include <ftxui/component/screen_interactive.hpp>
+
+using namespace ftxui;
+
+Component DummyWindowContent() {
+  class Impl : public ComponentBase {
+   private:
+    float scroll_x = 0.1;
+    float scroll_y = 0.1;
+
+   public:
+    Impl() {
+      auto content = Renderer([=] {
+        const std::string lorem =
+            "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed "
+            "do eiusmod tempor incididunt ut labore et dolore magna "
+            "aliqua. Ut enim ad minim veniam, quis nostrud exercitation "
+            "ullamco laboris nisi ut aliquip ex ea commodo consequat. Duis "
+            "aute irure dolor in reprehenderit in voluptate velit esse "
+            "cillum dolore eu fugiat nulla pariatur. Excepteur sint "
+            "occaecat cupidatat non proident, sunt in culpa qui officia "
+            "deserunt mollit anim id est laborum.";
+        return vbox({
+            text(lorem.substr(0, -1)),   text(lorem.substr(5, -1)),   text(""),
+            text(lorem.substr(10, -1)),  text(lorem.substr(15, -1)),  text(""),
+            text(lorem.substr(20, -1)),  text(lorem.substr(25, -1)),  text(""),
+            text(lorem.substr(30, -1)),  text(lorem.substr(35, -1)),  text(""),
+            text(lorem.substr(40, -1)),  text(lorem.substr(45, -1)),  text(""),
+            text(lorem.substr(50, -1)),  text(lorem.substr(55, -1)),  text(""),
+            text(lorem.substr(60, -1)),  text(lorem.substr(65, -1)),  text(""),
+            text(lorem.substr(70, -1)),  text(lorem.substr(75, -1)),  text(""),
+            text(lorem.substr(80, -1)),  text(lorem.substr(85, -1)),  text(""),
+            text(lorem.substr(90, -1)),  text(lorem.substr(95, -1)),  text(""),
+            text(lorem.substr(100, -1)), text(lorem.substr(105, -1)), text(""),
+            text(lorem.substr(110, -1)), text(lorem.substr(115, -1)), text(""),
+            text(lorem.substr(120, -1)), text(lorem.substr(125, -1)), text(""),
+            text(lorem.substr(130, -1)), text(lorem.substr(135, -1)), text(""),
+            text(lorem.substr(140, -1)),
+        });
+      });
+
+      auto scrollable_content = Renderer(content, [&, content] {
+        return content->Render() | focusPositionRelative(scroll_x, scroll_y) |
+               frame | flex;
+      });
+
+      SliderOption<float> option_x;
+      option_x.value = &scroll_x;
+      option_x.min = 0.f;
+      option_x.max = 1.f;
+      option_x.increment = 0.1f;
+      option_x.direction = Direction::Right;
+      option_x.color_active = Color::Blue;
+      option_x.color_inactive = Color::BlueLight;
+      auto scrollbar_x = Slider(option_x);
+
+      SliderOption<float> option_y;
+      option_y.value = &scroll_y;
+      option_y.min = 0.f;
+      option_y.max = 1.f;
+      option_y.increment = 0.1f;
+      option_y.direction = Direction::Down;
+      option_y.color_active = Color::Yellow;
+      option_y.color_inactive = Color::YellowLight;
+      auto scrollbar_y = Slider(option_y);
+
+      Add(Container::Vertical({
+          Container::Horizontal({
+              scrollable_content,
+              scrollbar_y,
+          }) | flex,
+          Container::Horizontal({
+              scrollbar_x,
+              Renderer([] { return text(L"x"); }),
+          }),
+      }));
+    }
+  };
+  return Make<Impl>();
+}
+
+int main() {
+  auto window_1 = Window({
+      .inner = DummyWindowContent(),
+      .title = "First window",
+      .width = 80,
+      .height = 30,
+  });
+
+  auto window_2 = Window({
+      .inner = DummyWindowContent(),
+      .title = "My window",
+      .left = 40,
+      .top = 20,
+      .width = 80,
+      .height = 30,
+  });
+
+  auto window_container = Container::Stacked({
+      window_1,
+      window_2,
+  });
+
+  auto screen = ScreenInteractive::Fullscreen();
+  screen.Loop(window_container);
+
+  return EXIT_SUCCESS;
+}

examples/component/selection.cpp

@@ -0,0 +1,87 @@
+// Copyright 2020 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <string>  // for char_traits, operator+, string, basic_string
+
+#include "ftxui/component/component.hpp"       // for Input, Renderer, Vertical
+#include "ftxui/component/component_base.hpp"  // for ComponentBase
+#include "ftxui/component/component_options.hpp"  // for InputOption
+#include "ftxui/component/screen_interactive.hpp"  // for Component, ScreenInteractive
+#include "ftxui/dom/elements.hpp"  // for text, hbox, separator, Element, operator|, vbox, border
+#include "ftxui/util/ref.hpp"  // for Ref
+
+using namespace ftxui;
+
+Element LoremIpsum() {
+  return vbox({
+      text("FTXUI: A powerful library for building user interfaces."),
+      text("Enjoy a rich set of components and a declarative style."),
+      text("Create beautiful and responsive UIs with minimal effort."),
+      text("Join the community and experience the power of FTXUI."),
+  });
+}
+
+int main() {
+  auto screen = ScreenInteractive::TerminalOutput();
+
+  auto quit =
+      Button("Quit", screen.ExitLoopClosure(), ButtonOption::Animated());
+
+  int selection_change_counter = 0;
+  std::string selection_content = "";
+  screen.SelectionChange([&] {
+    selection_change_counter++;
+    selection_content = screen.GetSelection();
+  });
+
+  // The components:
+  auto renderer = Renderer(quit, [&] {
+    return vbox({
+        text("Select changed: " + std::to_string(selection_change_counter) +
+             " times"),
+        text("Currently selected: "),
+        paragraph(selection_content) | vscroll_indicator | frame | border |
+            size(HEIGHT, EQUAL, 10),
+        window(text("Horizontal split"), hbox({
+                                             LoremIpsum(),
+                                             separator(),
+                                             LoremIpsum(),
+                                             separator(),
+                                             LoremIpsum(),
+                                         })),
+        window(text("Vertical split"), vbox({
+                                           LoremIpsum(),
+                                           separator(),
+                                           LoremIpsum(),
+                                           separator(),
+                                           LoremIpsum(),
+                                       })),
+        window(text("Grid split with different style"),
+               vbox({
+                   hbox({
+                       LoremIpsum(),
+                       separator(),
+                       LoremIpsum()                                   //
+                           | selectionBackgroundColor(Color::Yellow)  //
+                           | selectionColor(Color::Black)             //
+                           | selectionStyleReset,
+                       separator(),
+                       LoremIpsum() | selectionColor(Color::Blue),
+                   }),
+                   separator(),
+                   hbox({
+                       LoremIpsum() | selectionColor(Color::Red),
+                       separator(),
+                       LoremIpsum() | selectionStyle([](Pixel& pixel) {
+                         pixel.underlined_double = true;
+                       }),
+                       separator(),
+                       LoremIpsum(),
+                   }),
+               })),
+        quit->Render(),
+    });
+  });
+
+  screen.Loop(renderer);
+}

examples/dom/CMakeLists.txt

@@ -29,6 +29,7 @@ example(style_dim)
 example(style_gallery)
 example(style_hyperlink)
 example(style_inverted)
+example(style_italic)
 example(style_strikethrough)
 example(style_underlined)
 example(style_underlined_double)

examples/dom/style_gallery.cpp

@@ -15,6 +15,7 @@ int main() {
     hbox({
       text("normal")                                    , text(" ") ,
       text("bold")               | bold                 , text(" ") ,
+      text("italic")             | italic               , text(" ") ,
       text("dim")                | dim                  , text(" ") ,
       text("inverted")           | inverted             , text(" ") ,
       text("underlined")         | underlined           , text(" ") ,

examples/dom/style_italic.cpp

@@ -0,0 +1,23 @@
+// Copyright 2025 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <ftxui/dom/elements.hpp>  // for text, operator|, inverted, Fit, hbox, Element
+#include <ftxui/screen/screen.hpp>  // for Full, Screen
+#include <memory>                   // for allocator
+
+#include "ftxui/dom/node.hpp"      // for Render
+#include "ftxui/screen/color.hpp"  // for ftxui
+
+int main() {
+  using namespace ftxui;
+  auto document = hbox({
+      text("This text is "),
+      text("italic") | italic,
+      text(". Do you like it?"),
+  });
+  auto screen = Screen::Create(Dimension::Full(), Dimension::Fit(document));
+  Render(screen, document);
+  screen.Print();
+
+  return 0;
+}

examples/index.css

@@ -0,0 +1,107 @@
+@import url(https://fonts.googleapis.com/css?family=Khula:700);
+
+body {
+  background-color:#EEE;
+  padding:0px;
+  margin:0px;
+  font-family: Khula, Helvetica, sans-serif;
+  font-size: 130%;
+}
+
+.page {
+  max-width:1300px;
+  margin: auto;
+  padding: 10px;
+}
+
+a {
+  box-shadow: inset 0 0 0 0 #54b3d6;
+  color: #0087b9;
+  margin: 0 -.25rem;
+  padding: 0 .25rem;
+  transition: color .3s ease-in-out,
+              box-shadow .3s ease-in-out;
+}
+
+a:hover {
+  box-shadow: inset 120px 0 0 0 #54b3d6;
+  color: white;
+}
+
+h1 {
+  text-decoration: underline;
+  width:100%;
+  background-color: rgba(100,100,255,0.5);
+  padding: 10px;
+  margin: 0;
+}
+
+
+#selectExample {
+  flex:1;
+}
+
+#selectExample, #selectExample option {
+  font-size: 16px;
+  font-family: sans-serif;
+  font-weight: 700;
+  line-height: 1.3;
+  border:0px;
+  background-color: #bbb;
+  color:black;
+}
+
+#selectExample:focus {
+  outline:none;
+}
+
+#terminal {
+  width:100%;
+  height 500px;
+  height: calc(clamp(200px, 100vh - 300px, 900px));
+  overflow: hidden;
+  border:none;
+  background-color:black;
+}
+
+#terminalContainer {
+  overflow: hidden;
+  border-radius: 10px;
+  box-shadow: 0px 2px 10px 0px rgba(0,0,0,0.75),
+  0px 2px 80px 0px rgba(0,0,0,0.50);
+}
+
+.fakeButtons {
+  height: 10px;
+  width: 10px;
+  border-radius: 50%;
+  border: 1px solid #000;
+  margin:6px;
+  background-color: #ff3b47;
+  border-color: #9d252b;
+  display: inline-block;
+}
+
+.fakeMinimize {
+  left: 11px;
+  background-color: #ffc100;
+  border-color: #9d802c;
+}
+
+.fakeZoom {
+  left: 16px;
+  background-color: #00d742;
+  border-color: #049931;
+}
+
+.fakeMenu {
+  display:flex;
+  flex-direction: row;
+  width:100%;
+  box-sizing: border-box;
+  height: 25px;
+  background-color: #bbb;
+  color:black;
+  margin: 0 auto;
+  overflow: hidden;
+}

examples/index.html

@@ -1,174 +1,32 @@
-<!DOCTYPE html> <html lang="en">
+<!DOCTYPE html>
+<html lang="en">
   <head>
     <meta charset="utf-8">
     <title>FTXUI examples WebAssembly</title>
-    <script src="https://cdn.jsdelivr.net/npm/xterm@4.18.0/lib/xterm.min.js"></script>
-    <script src="https://cdn.jsdelivr.net/npm/xterm-addon-webgl@0.11.4/lib/xterm-addon-webgl.min.js"></script>
-    <script src="https://cdn.jsdelivr.net/npm/xterm-addon-fit@0.5.0/lib/xterm-addon-fit.min.js"></script>
+    <link rel="icon" href="data:image/svg+xml,<svg xmlns=%22http://www.w3.org/2000/svg%22 viewBox=%220 0 100 100%22><text y=%22.9em%22 font-size=%2290%22>➡️</text></svg>">
+    <link rel="stylesheet" href="index.css">
     <link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/xterm@4.11.0/css/xterm.css"></link>
-    <!--Add COOP/COEP via a ServiceWorker to use SharedArrayBuffer-->
-    <script>
-      if ("serviceWorker" in navigator && !window.crossOriginIsolated) {
-        navigator.serviceWorker.register(new URL("./sw.js", location.href)).then(
-          registration => {
-            if (registration.active && !navigator.serviceWorker.controller) {
-              window.location.reload();
-            }
-          },
-        );
-      } 
-    </script>
+    <script type="module" src="index.mjs"></script>
   </head>
   <body>
     <script id="example_script"></script>
+
     <div class="page">
-      <h1>FTXUI WebAssembly Example </h1>
       <p>
         <a href="https://github.com/ArthurSonzogni/FTXUI">FTXUI</a> is a simple
         functional C++ library for terminal user interface. <br/>
         This showcases the: <a href="https://github.com/ArthurSonzogni/FTXUI/tree/master/examples">./example/</a> folder. <br/>
       </p>
-      <p>
-        On this page, you can try all the examples contained in: <a
-        href="https://github.com/ArthurSonzogni/FTXUI/tree/master/examples">./example/</a>
-        Those are compiled using WebAssembly.
-      </p>
-      <select id="selectExample"></select>
-      <div id="terminal"></div>
+
+      <div id="terminalContainer">
+        <div class="fakeMenu">
+          <div class="fakeButtons fakeClose"></div>
+          <div class="fakeButtons fakeMinimize"></div>
+          <div class="fakeButtons fakeZoom"></div>
+          <select id="selectExample"></select>
+        </div>
+        <div id="terminal"></div>
+      </div>
     </div>
   </body>
-  <script>
-    const example_list = "@EXAMPLES@".split(";");
-
-    const url_search_params = new URLSearchParams(window.location.search);
-    const example = url_search_params.get("file") || "dom/color_gallery";
-    const select = document.getElementById("selectExample"); 
-
-    for(var i = 0; i < example_list.length; i++) {
-        var opt = example_list[i];
-        var el = document.createElement("option");
-        el.textContent = opt;
-        el.value = opt;
-        select.appendChild(el);
-    }
-    select.selectedIndex = example_list.findIndex(path => path == example) || 0;
-    select.addEventListener("change", () => {
-      location.href = (location.href).split('?')[0] + "?file=" +
-            example_list[select.selectedIndex];
-    });
-
-    let stdin_buffer = [];
-    const stdin = () => {
-      return stdin_buffer.shift() || 0;
-    }
-
-    let stdout_buffer = [];
-    const stdout = code => {
-      if (code == 0) {
-        term.write(new Uint8Array(stdout_buffer));
-        stdout_buffer = [];
-      } else {
-        stdout_buffer.push(code)
-      }
-    }
-    let stderrbuffer = [];
-    const stderr = code => {
-      if (code == 0 || code == 10) {
-        console.error(String.fromCodePoint(...stderrbuffer));
-        stderrbuffer = [];
-      } else {
-        stderrbuffer.push(code)
-      }
-    }
-    const term = new Terminal();
-    const term_element = document.querySelector('#terminal');
-    term.open(term_element);
-
-    const webgl_addon = new (WebglAddon.WebglAddon)();
-    term.loadAddon(webgl_addon);
-
-    const onBinary = e => {
-      for(c of e)
-        stdin_buffer.push(c.charCodeAt(0));
-    }
-    term.onBinary(onBinary);
-    term.onData(onBinary)
-    term.resize(140,43);
-    window.Module = {
-      preRun: () => {
-        FS.init(stdin, stdout, stderr);
-      },
-      postRun: [],
-      onRuntimeInitialized: () => {
-        if (window.Module._ftxui_on_resize == undefined)
-          return;
-
-        const fit_addon = new (FitAddon.FitAddon)();
-        term.loadAddon(fit_addon);
-        fit_addon.fit();
-        const resize_handler = () => {
-          const {cols, rows} = fit_addon.proposeDimensions();
-          term.resize(cols, rows);
-          window.Module._ftxui_on_resize(cols, rows);
-        };
-        const resize_observer = new ResizeObserver(resize_handler);
-        resize_observer.observe(term_element);
-        resize_handler();
-
-        // Disable scrollbar
-        term.write('\x1b[?47h')
-      },
-    };
-
-    const words = example.split('/')
-    words[1] = "ftxui_example_" + words[1] + ".js"
-    document.querySelector("#example_script").src = words.join('/');
-  </script>
-
-  <style>
-
-    body {
-      background-color:#EEE;
-      padding:20px;
-      font-family: Helvetica, sans-serif;
-      font-size: 130%;
-    }
-
-    .page {
-      max-width:1300px;
-      margin: auto;
-    }
-
-    h1 {
-      text-decoration: underline;
-    }
-
-    select {
-      display:block;
-      padding: .6em 1.4em .5em .8em;
-      border-radius: 20px 20px 0px 0px;
-      font-size: 16px;
-      font-family: sans-serif;
-      font-weight: 700;
-
-      color: #444;
-      line-height: 1.3;
-      background-color:black;
-      border:0px;
-      color:white;
-      transition: color 0.2s linear;
-      transition: background-color 0.2s linear;
-    }
-
-    #terminal {
-      width:100%;
-      height: 500px;
-      height: calc(clamp(200px, 100vh - 300px, 900px));
-      overflow: hidden;
-      border:none;
-      padding:auto;
-    }
-
-  </style>
-
 </html>

examples/index.mjs

@@ -0,0 +1,100 @@
+import xterm             from 'https://cdn.jsdelivr.net/npm/xterm@4.18.0/+esm'
+import xterm_addon_webgl from 'https://cdn.jsdelivr.net/npm/xterm-addon-webgl@0.11.4/+esm'
+import xterm_addon_fit   from 'https://cdn.jsdelivr.net/npm/xterm-addon-fit@0.5.0/+esm'
+
+// Add COOP/COEP via a ServiceWorker to use SharedArrayBuffer
+if ("serviceWorker" in navigator && !window.crossOriginIsolated) {
+  const url_sw = new URL("./sw.js", location.href);
+  const registration = await navigator.serviceWorker.register(url_sw);
+  window.location.reload(); // Reload to ensure the COOP/COEP headers are set.
+} 
+
+const example_list = "@EXAMPLES@".split(";");
+const url_search_params = new URLSearchParams(window.location.search);
+
+const select = document.getElementById("selectExample"); 
+for(const example of example_list) {
+  const option = document.createElement("option");
+  option.textContent = example;
+  option.value = example;
+  select.appendChild(option);
+}
+const example = url_search_params.get("file") || "dom/color_gallery";
+select.selectedIndex = example_list.findIndex(path => path == example) || 0;
+select.addEventListener("change", () => {
+  history.pushState({}, "", "?file=" + example_list[select.selectedIndex]);
+  location.reload();
+});
+
+const term_element = document.querySelector('#terminal');
+const term = new xterm.Terminal();
+term.options.scrollback = 0;
+term.open(term_element);
+const fit_addon = new xterm_addon_fit.FitAddon();
+const webgl_addon = new xterm_addon_webgl.WebglAddon();
+term.loadAddon(webgl_addon);
+term.loadAddon(fit_addon);
+
+const stdin_buffer = [];
+const stdout_buffer = [];
+const stderr_buffer = [];
+
+const stdin = () => {
+  return stdin_buffer.shift() || 0;
+}
+
+const stdout = code => {
+  if (code == 0) {
+    term.write(new Uint8Array(stdout_buffer));
+    stdout_buffer.length = 0;
+  } else {
+    stdout_buffer.push(code)
+  }
+}
+
+const stderr = code => {
+  if (code == 0 || code == 10) {
+    console.error(String.fromCodePoint(...stderr_buffer));
+    stderr_buffer = [];
+  } else {
+    stderr_buffer.push(code)
+  }
+}
+
+const onBinary = e => {
+  for(const c of e)
+    stdin_buffer.push(c.charCodeAt(0));
+}
+
+term.onBinary(onBinary);
+term.onData(onBinary)
+term.resize(140,43);
+
+window.Module = {
+  preRun: () => {
+    FS.init(stdin, stdout, stderr);
+  },
+  postRun: [],
+  onRuntimeInitialized: () => {
+    if (window.Module._ftxui_on_resize == undefined)
+      return;
+    fit_addon.fit();
+
+    const resize_handler = () => {
+      const {cols, rows} = fit_addon.proposeDimensions();
+      term.resize(cols, rows);
+      window.Module._ftxui_on_resize(cols, rows);
+      fit_addon.fit();
+    };
+    const resize_observer = new ResizeObserver(resize_handler);
+    resize_observer.observe(term_element);
+    resize_handler();
+
+    // Disable scrollbar
+    //term.write('\x1b[?47h')
+  },
+};
+
+const words = example.split('/')
+words[1] = "ftxui_example_" + words[1] + ".js"
+document.querySelector("#example_script").src = words.join('/');

flake.lock

@@ -1,12 +1,15 @@
 {
   "nodes": {
     "flake-utils": {
+      "inputs": {
+        "systems": "systems"
+      },
       "locked": {
-        "lastModified": 1678901627,
-        "narHash": "sha256-U02riOqrKKzwjsxc/400XnElV+UtPUQWpANPlyazjH0=",
+        "lastModified": 1694529238,
+        "narHash": "sha256-zsNZZGTGnMOf9YpHKJqMSsa0dXbfmxeoJ7xHlrt+xmY=",
         "owner": "numtide",
         "repo": "flake-utils",
-        "rev": "93a2b84fc4b70d9e089d029deacc3583435c2ed6",
+        "rev": "ff7b65b44d01cf9ba6a71320833626af21126384",
         "type": "github"
       },
       "original": {
@@ -17,11 +20,11 @@
     },
     "nixpkgs": {
       "locked": {
-        "lastModified": 1679734080,
-        "narHash": "sha256-z846xfGLlon6t9lqUzlNtBOmsgQLQIZvR6Lt2dImk1M=",
+        "lastModified": 1697915759,
+        "narHash": "sha256-WyMj5jGcecD+KC8gEs+wFth1J1wjisZf8kVZH13f1Zo=",
         "owner": "NixOS",
         "repo": "nixpkgs",
-        "rev": "dbf5322e93bcc6cfc52268367a8ad21c09d76fea",
+        "rev": "51d906d2341c9e866e48c2efcaac0f2d70bfd43e",
         "type": "github"
       },
       "original": {
@@ -36,6 +39,21 @@
         "flake-utils": "flake-utils",
         "nixpkgs": "nixpkgs"
       }
+    },
+    "systems": {
+      "locked": {
+        "lastModified": 1681028828,
+        "narHash": "sha256-Vy1rq5AaRuLzOxct8nz4T6wlgyUR7zLU309k9mBC768=",
+        "owner": "nix-systems",
+        "repo": "default",
+        "rev": "da67096a3b9bf56a91d16901293e51ba5b49a27e",
+        "type": "github"
+      },
+      "original": {
+        "owner": "nix-systems",
+        "repo": "default",
+        "type": "github"
+      }
     }
   },
   "root": "root",

flake.nix

@@ -8,9 +8,11 @@
 
   outputs = {self, nixpkgs, flake-utils}:
     flake-utils.lib.eachDefaultSystem (system:
-      let pkgs = import nixpkgs { inherit system; }; in
-      {
-        packages.ftxui = pkgs.stdenv.mkDerivation rec {
+    let pkgs = import nixpkgs { inherit system; }; in
+    let llvm = pkgs.llvmPackages_latest; in
+    {
+      packages = rec {
+        default = pkgs.stdenv.mkDerivation rec {
           pname = "ftxui";
           version = "v4.0.0";
           src = pkgs.fetchFromGitHub {
@@ -56,6 +58,19 @@
             platforms = pkgs.lib.platforms.all;
           };
         };
-      }
-    );
+
+        ftxui = default;
+      };
+
+      devShells = {
+        default = pkgs.mkShell {
+          nativeBuildInputs = [
+            pkgs.cmake
+            pkgs.clang-tools
+            llvm.clang
+          ];
+        };
+      };
+    }
+  );
 }

include/ftxui/component/component_base.hpp

@@ -44,12 +44,16 @@ class ComponentBase {
   ComponentBase* Parent() const;
   Component& ChildAt(size_t i);
   size_t ChildCount() const;
+  int Index() const;
   void Add(Component children);
   void Detach();
   void DetachAllChildren();
 
   // Renders the component.
-  virtual Element Render();
+  Element Render();
+
+  // Override this function modify how `Render` works.
+  virtual Element OnRender();
 
   // Handles an event.
   // By default, reduce on children with a lazy OR.
@@ -93,6 +97,7 @@ class ComponentBase {
 
  private:
   ComponentBase* parent_ = nullptr;
+  bool in_render = false;
 };
 
 }  // namespace ftxui

include/ftxui/component/component_options.hpp

@@ -25,6 +25,7 @@ struct EntryState {
   bool state;         ///< The state of the button/checkbox/radiobox
   bool active;        ///< Whether the entry is the active one.
   bool focused;       ///< Whether the entry is one focused by the user.
+  int index;          ///< Index of the entry when applicable or -1.
 };
 
 struct UnderlineOption {

include/ftxui/component/screen_interactive.hpp

@@ -16,6 +16,7 @@
 #include "ftxui/component/captured_mouse.hpp"  // for CapturedMouse
 #include "ftxui/component/event.hpp"           // for Event
 #include "ftxui/component/task.hpp"            // for Task, Closure
+#include "ftxui/dom/selection.hpp"             // for SelectionOption
 #include "ftxui/screen/screen.hpp"             // for Screen
 
 namespace ftxui {
@@ -68,6 +69,10 @@ class ScreenInteractive : public Screen {
   void ForceHandleCtrlC(bool force);
   void ForceHandleCtrlZ(bool force);
 
+  // Selection API.
+  std::string GetSelection();
+  void SelectionChange(std::function<void()> callback);
+
  private:
   void ExitNow();
 
@@ -82,6 +87,8 @@ class ScreenInteractive : public Screen {
   void RunOnceBlocking(Component component);
 
   void HandleTask(Component component, Task& task);
+  bool HandleSelection(bool handled, Event event);
+  void RefreshSelection();
   void Draw(Component component);
   void ResetCursorPosition();
 
@@ -129,6 +136,22 @@ class ScreenInteractive : public Screen {
   // The style of the cursor to restore on exit.
   int cursor_reset_shape_ = 1;
 
+  // Selection API:
+  CapturedMouse selection_pending_;
+  struct SelectionData {
+    int start_x = -1;
+    int start_y = -1;
+    int end_x = -2;
+    int end_y = -2;
+    bool empty = true;
+    bool operator==(const SelectionData& other) const;
+    bool operator!=(const SelectionData& other) const;
+  };
+  SelectionData selection_data_;
+  SelectionData selection_data_previous_;
+  std::unique_ptr<Selection> selection_;
+  std::function<void()> selection_on_change_;
+
   friend class Loop;
 
  public:

include/ftxui/dom/elements.hpp

@@ -95,6 +95,7 @@ Element canvas(std::function<void(Canvas&)>);
 // -- Decorator ---
 Element bold(Element);
 Element dim(Element);
+Element italic(Element);
 Element inverted(Element);
 Element underlined(Element);
 Element underlinedDouble(Element);
@@ -113,6 +114,11 @@ Decorator focusPositionRelative(float x, float y);
 Element automerge(Element child);
 Decorator hyperlink(std::string link);
 Element hyperlink(std::string link, Element child);
+Element selectionStyleReset(Element);
+Decorator selectionColor(Color foreground);
+Decorator selectionBackgroundColor(Color foreground);
+Decorator selectionForegroundColor(Color foreground);
+Decorator selectionStyle(std::function<void(Pixel&)> style);
 
 // --- Layout is
 // Horizontal, Vertical or stacked set of elements.
@@ -156,7 +162,7 @@ Element frame(Element);
 Element xframe(Element);
 Element yframe(Element);
 Element focus(Element);
-Element select(Element);
+Element select(Element e);  // Deprecated - Alias for focus.
 
 // --- Cursor ---
 // Those are similar to `focus`, but also change the shape of the cursor.

include/ftxui/dom/node.hpp

@@ -8,6 +8,7 @@
 #include <vector>  // for vector
 
 #include "ftxui/dom/requirement.hpp"  // for Requirement
+#include "ftxui/dom/selection.hpp"    // for Selection
 #include "ftxui/screen/box.hpp"       // for Box
 #include "ftxui/screen/screen.hpp"
 
@@ -22,7 +23,7 @@ using Elements = std::vector<Element>;
 class Node {
  public:
   Node();
-  Node(Elements children);
+  explicit Node(Elements children);
   Node(const Node&) = delete;
   Node(const Node&&) = delete;
   Node& operator=(const Node&) = delete;
@@ -40,9 +41,15 @@ class Node {
   //         Propagated from Parents to Children.
   virtual void SetBox(Box box);
 
-  // Step 3: Draw this element.
+  // Step 3: (optional) Selection
+  //         Propagated from Parents to Children.
+  virtual void Select(Selection& selection);
+
+  // Step 4: Draw this element.
   virtual void Render(Screen& screen);
 
+  virtual std::string GetSelectedContent(Selection& selection);
+
   // Layout may not resolve within a single iteration for some elements. This
   // allows them to request additionnal iterations. This signal must be
   // forwarded to children at least once.
@@ -52,6 +59,8 @@ class Node {
   };
   virtual void Check(Status* status);
 
+  friend void Render(Screen& screen, Node* node, Selection& selection);
+
  protected:
   Elements children_;
   Requirement requirement_;
@@ -60,6 +69,10 @@ class Node {
 
 void Render(Screen& screen, const Element& element);
 void Render(Screen& screen, Node* node);
+void Render(Screen& screen, Node* node, Selection& selection);
+std::string GetNodeSelectedContent(Screen& screen,
+                                   Node* node,
+                                   Selection& selection);
 
 }  // namespace ftxui
 

include/ftxui/dom/requirement.hpp

@@ -5,8 +5,10 @@
 #define FTXUI_DOM_REQUIREMENT_HPP
 
 #include "ftxui/screen/box.hpp"
+#include "ftxui/screen/screen.hpp"
 
 namespace ftxui {
+class Node;
 
 struct Requirement {
   // The required size to fully draw the element.
@@ -20,13 +22,28 @@ struct Requirement {
   int flex_shrink_y = 0;
 
   // Focus management to support the frame/focus/select element.
-  enum Selection {
-    NORMAL = 0,
-    SELECTED = 1,
-    FOCUSED = 2,
+  struct Focused {
+    bool enabled = false;
+    Box box;
+    Node* node = nullptr;
+    Screen::Cursor::Shape cursor_shape = Screen::Cursor::Shape::Hidden;
+
+    // Internal for interactions with components.
+    bool component_active = false;
+
+    // Return whether this requirement should be preferred over the other.
+    bool Prefer(const Focused& other) const {
+      if (!other.enabled) {
+        return false;
+      }
+      if (!enabled) {
+        return true;
+      }
+
+      return other.component_active && !component_active;
+    }
   };
-  Selection selection = NORMAL;
-  Box selected_box;
+  Focused focused;
 };
 
 }  // namespace ftxui

include/ftxui/dom/selection.hpp

@@ -0,0 +1,50 @@
+// Copyright 2024 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+
+#ifndef FTXUI_DOM_SELECTION_HPP
+#define FTXUI_DOM_SELECTION_HPP
+
+#include <functional>
+
+#include <sstream>
+#include "ftxui/screen/box.hpp"    // for Box
+#include "ftxui/screen/pixel.hpp"  // for Pixel
+
+namespace ftxui {
+
+/// @brief Represent a selection in the terminal.
+class Selection {
+ public:
+  Selection();  // Empty selection.
+  Selection(int start_x, int start_y, int end_x, int end_y);
+
+  const Box& GetBox() const;
+
+  Selection SaturateHorizontal(Box box);
+  Selection SaturateVertical(Box box);
+  bool IsEmpty() const { return empty_; }
+
+  void AddPart(const std::string& part, int y, int left, int right);
+  std::string GetParts() { return parts_.str(); }
+
+ private:
+  Selection(int start_x, int start_y, int end_x, int end_y, Selection* parent);
+
+  const int start_x_ = 0;
+  const int start_y_ = 0;
+  const int end_x_ = 0;
+  const int end_y_ = 0;
+  const Box box_ = {};
+  Selection* const parent_ = this;
+  const bool empty_ = true;
+  std::stringstream parts_;
+
+  // The position of the last inserted part.
+  int x_ = 0;
+  int y_ = 0;
+};
+
+}  // namespace ftxui
+
+#endif /* end of include guard: FTXUI_DOM_SELECTION_HPP */

include/ftxui/dom/table.hpp

@@ -36,8 +36,8 @@ class TableSelection;
 class Table {
  public:
   Table();
-  Table(std::vector<std::vector<std::string>>);
-  Table(std::vector<std::vector<Element>>);
+  explicit Table(std::vector<std::vector<std::string>>);
+  explicit Table(std::vector<std::vector<Element>>);
   Table(std::initializer_list<std::vector<std::string>> init);
   TableSelection SelectAll();
   TableSelection SelectCell(int column, int row);

include/ftxui/screen/box.hpp

@@ -14,6 +14,7 @@ struct Box {
 
   static auto Intersection(Box a, Box b) -> Box;
   static auto Union(Box a, Box b) -> Box;
+  void Shift(int x, int y);
   bool Contain(int x, int y) const;
   bool IsEmpty() const;
   bool operator==(const Box& other) const;

include/ftxui/screen/pixel.hpp

@@ -17,6 +17,7 @@ struct Pixel {
       : blink(false),
         bold(false),
         dim(false),
+        italic(false),
         inverted(false),
         underlined(false),
         underlined_double(false),
@@ -27,6 +28,7 @@ struct Pixel {
   bool blink : 1;
   bool bold : 1;
   bool dim : 1;
+  bool italic : 1;
   bool inverted : 1;
   bool underlined : 1;
   bool underlined_double : 1;

include/ftxui/screen/screen.hpp

@@ -4,12 +4,14 @@
 #ifndef FTXUI_SCREEN_SCREEN_HPP
 #define FTXUI_SCREEN_SCREEN_HPP
 
-#include <cstdint>  // for uint8_t
-#include <string>   // for string, basic_string, allocator
-#include <vector>   // for vector
+#include <cstdint>     // for uint8_t
+#include <functional>  // for function
+#include <string>      // for string, basic_string, allocator
+#include <vector>      // for vector
 
 #include "ftxui/screen/image.hpp"     // for Pixel, Image
 #include "ftxui/screen/terminal.hpp"  // for Dimensions
+#include "ftxui/util/autoreset.hpp"   // for AutoReset
 
 namespace ftxui {
 
@@ -67,9 +69,18 @@ class Screen : public Image {
   uint8_t RegisterHyperlink(const std::string& link);
   const std::string& Hyperlink(uint8_t id) const;
 
+  using SelectionStyle = std::function<void(Pixel&)>;
+  const SelectionStyle& GetSelectionStyle() const;
+  void SetSelectionStyle(SelectionStyle decorator);
+
  protected:
   Cursor cursor_;
   std::vector<std::string> hyperlinks_ = {""};
+
+  // The current selection style. This is overridden by various dom elements.
+  SelectionStyle selection_style_ = [](Pixel& pixel) {
+    pixel.inverted ^= true;
+  };
 };
 
 }  // namespace ftxui

src/ftxui/component/button.cpp

@@ -37,7 +37,7 @@ class ButtonBase : public ComponentBase, public ButtonOption {
   explicit ButtonBase(ButtonOption option) : ButtonOption(std::move(option)) {}
 
   // Component implementation:
-  Element Render() override {
+  Element OnRender() override {
     const bool active = Active();
     const bool focused = Focused();
     const bool focused_or_hover = focused || mouse_hover_;
@@ -47,17 +47,16 @@ class ButtonBase : public ComponentBase, public ButtonOption {
       SetAnimationTarget(target);
     }
 
-    auto focus_management = focused ? focus : active ? select : nothing;
-    const EntryState state = {
-        *label,
-        false,
-        active,
-        focused_or_hover,
+    const EntryState state{
+        *label, false, active, focused_or_hover, Index(),
     };
 
     auto element = (transform ? transform : DefaultTransform)  //
         (state);
-    return element | AnimatedColorStyle() | focus_management | reflect(box_);
+    element |= AnimatedColorStyle();
+    element |= focus;
+    element |= reflect(box_);
+    return element;
   }
 
   Decorator AnimatedColorStyle() {

src/ftxui/component/checkbox.cpp

@@ -23,19 +23,17 @@ class CheckboxBase : public ComponentBase, public CheckboxOption {
 
  private:
   // Component implementation.
-  Element Render() override {
+  Element OnRender() override {
     const bool is_focused = Focused();
     const bool is_active = Active();
-    auto focus_management = is_focused ? focus : is_active ? select : nothing;
     auto entry_state = EntryState{
-        *label,
-        *checked,
-        is_active,
-        is_focused || hovered_,
+        *label, *checked, is_active, is_focused || hovered_, -1,
     };
     auto element = (transform ? transform : CheckboxOption::Simple().transform)(
         entry_state);
-    return element | focus_management | reflect(box_);
+    element |= focus;
+    element |= reflect(box_);
+    return element;
   }
 
   bool OnEvent(Event event) override {
@@ -72,7 +70,6 @@ class CheckboxBase : public ComponentBase, public CheckboxOption {
         event.mouse().motion == Mouse::Pressed) {
       *checked = !*checked;
       on_change();
-      TakeFocus();
       return true;
     }
 

src/ftxui/component/component.cpp

@@ -15,6 +15,8 @@
 #include "ftxui/component/event.hpp"           // for Event
 #include "ftxui/component/screen_interactive.hpp"  // for Component, ScreenInteractive
 #include "ftxui/dom/elements.hpp"                  // for text, Element
+#include "ftxui/dom/node.hpp"                      // for Node, Elements
+#include "ftxui/screen/box.hpp"                    // for Box
 
 namespace ftxui::animation {
 class Params;
@@ -51,6 +53,22 @@ size_t ComponentBase::ChildCount() const {
   return children_.size();
 }
 
+/// @brief Return index of the component in its parent. -1 if no parent.
+/// @ingroup component
+int ComponentBase::Index() const {
+  if (parent_ == nullptr) {
+    return -1;
+  }
+  int index = 0;
+  for (const Component& child : parent_->children_) {
+    if (child.get() == this) {
+      return index;
+    }
+    index++;
+  }
+  return -1;  // Not reached.
+}
+
 /// @brief Add a child.
 /// @@param child The child to be attached.
 /// @ingroup component
@@ -87,10 +105,46 @@ void ComponentBase::DetachAllChildren() {
 }
 
 /// @brief Draw the component.
-/// Build a ftxui::Element to be drawn on the ftxi::Screen representing this
-/// ftxui::ComponentBase.
+/// Build a ftxui::Element to be drawn on the ftxui::Screen representing this
+/// ftxui::ComponentBase. Please override OnRender() to modify the rendering.
 /// @ingroup component
 Element ComponentBase::Render() {
+  // Some users might call `ComponentBase::Render()` from
+  // `T::OnRender()`. To avoid infinite recursion, we use a flag.
+  if (in_render) {
+    return ComponentBase::OnRender();
+  }
+
+  in_render = true;
+  Element element = OnRender();
+  in_render = false;
+
+  class Wrapper : public Node {
+   public:
+    bool active_ = false;
+
+    Wrapper(Element child, bool active)
+        : Node({std::move(child)}), active_(active) {}
+
+    void SetBox(Box box) override {
+      Node::SetBox(box);
+      children_[0]->SetBox(box);
+    }
+
+    void ComputeRequirement() override {
+      Node::ComputeRequirement();
+      requirement_.focused.component_active = active_;
+    }
+  };
+
+  return std::make_shared<Wrapper>(std::move(element), Active());
+}
+
+/// @brief Draw the component.
+/// Build a ftxui::Element to be drawn on the ftxi::Screen representing this
+/// ftxui::ComponentBase. This function is means to be overridden.
+/// @ingroup component
+Element ComponentBase::OnRender() {
   if (children_.size() == 1) {
     return children_.front()->Render();
   }

src/ftxui/component/container.cpp

@@ -98,7 +98,7 @@ class VerticalContainer : public ContainerBase {
  public:
   using ContainerBase::ContainerBase;
 
-  Element Render() override {
+  Element OnRender() override {
     Elements elements;
     elements.reserve(children_.size());
     for (auto& it : children_) {
@@ -163,6 +163,7 @@ class VerticalContainer : public ContainerBase {
       return false;
     }
 
+    const int old_selected = *selector_;
     if (event.mouse().button == Mouse::WheelUp) {
       MoveSelector(-1);
     }
@@ -171,7 +172,7 @@ class VerticalContainer : public ContainerBase {
     }
     *selector_ = std::max(0, std::min(int(children_.size()) - 1, *selector_));
 
-    return true;
+    return old_selected != *selector_;
   }
 
   Box box_;
@@ -181,7 +182,7 @@ class HorizontalContainer : public ContainerBase {
  public:
   using ContainerBase::ContainerBase;
 
-  Element Render() override {
+  Element OnRender() override {
     Elements elements;
     elements.reserve(children_.size());
     for (auto& it : children_) {
@@ -217,7 +218,7 @@ class TabContainer : public ContainerBase {
  public:
   using ContainerBase::ContainerBase;
 
-  Element Render() override {
+  Element OnRender() override {
     const Component active_child = ActiveChild();
     if (active_child) {
       return active_child->Render();
@@ -243,7 +244,7 @@ class StackedContainer : public ContainerBase {
       : ContainerBase(std::move(children), nullptr) {}
 
  private:
-  Element Render() final {
+  Element OnRender() final {
     Elements elements;
     for (auto& child : children_) {
       elements.push_back(child->Render());
@@ -333,7 +334,7 @@ Component Vertical(Components children) {
 ///   children_2,
 ///   children_3,
 ///   children_4,
-/// });
+/// }, &selected_children);
 /// ```
 Component Vertical(Components children, int* selector) {
   return std::make_shared<VerticalContainer>(std::move(children), selector);
@@ -354,7 +355,7 @@ Component Vertical(Components children, int* selector) {
 ///   children_2,
 ///   children_3,
 ///   children_4,
-/// }, &selected_children);
+/// });
 /// ```
 Component Horizontal(Components children) {
   return Horizontal(std::move(children), nullptr);

src/ftxui/component/dropdown.cpp

@@ -44,10 +44,14 @@ Component Dropdown(DropdownOption option) {
       }));
     }
 
-    Element Render() override {
-      radiobox.selected =
+    Element OnRender() override {
+      selected_ =
           util::clamp(radiobox.selected(), 0, int(radiobox.entries.size()) - 1);
-      title_ = radiobox.entries[selected_()];
+      selected_ = util::clamp(selected_(), 0, int(radiobox.entries.size()) - 1);
+
+      if (selected_() >= 0 && selected_() < int(radiobox.entries.size())) {
+        title_ = radiobox.entries[selected_()];
+      }
 
       return transform(*open_, checkbox_->Render(), radiobox_->Render());
     }
@@ -66,10 +70,13 @@ Component Dropdown(DropdownOption option) {
       // Auto-close the dropdown when the user selects an item, even if the item
       // it the same as the previous one.
       if (open_old && open_()) {
-        const bool should_close = (selected_() != selected_old) ||     //
-                                  (event == Event::Return) ||          //
-                                  (event == Event::Character(' ')) ||  //
-                                  (event == Event::Escape);            //
+        const bool should_close =
+            (selected_() != selected_old) ||     //
+            (event == Event::Return) ||          //
+            (event == Event::Character(' ')) ||  //
+            (event == Event::Escape) ||          //
+            (event.is_mouse() && event.mouse().button == Mouse::Left &&
+             event.mouse().motion == Mouse::Pressed);
 
         if (should_close) {
           checkbox_->TakeFocus();

src/ftxui/component/dropdown_test.cpp

@@ -0,0 +1,34 @@
+// Copyright 2025 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+
+#include "ftxui/component/component.hpp"  // for Horizontal, Vertical, Button, Tab
+#include "ftxui/component/component_base.hpp"  // for ComponentBase, Component
+#include "ftxui/component/event.hpp"  // for Event, Event::Tab, Event::TabReverse, Event::ArrowDown, Event::ArrowLeft, Event::ArrowRight, Event::ArrowUp
+#include "gtest/gtest.h"  // for AssertionResult, Message, TestPartResult, EXPECT_EQ, EXPECT_FALSE, Test, EXPECT_TRUE, TEST
+
+namespace ftxui {
+
+TEST(DropdownTest, Empty) {
+  std::vector<std::string> list = {};
+  int index = 0;
+  auto dropdown = Dropdown(list, &index);
+
+  dropdown->OnEvent(Event::Return);
+
+  auto screen = Screen(8, 8);
+  auto document = dropdown->Render();
+  Render(screen, document);
+
+  EXPECT_EQ(screen.ToString(),
+            "╭──────╮\r\n"
+            "│↓     │\r\n"
+            "├──────┤\r\n"
+            "│      │\r\n"
+            "│      │\r\n"
+            "│      │\r\n"
+            "│      │\r\n"
+            "╰──────╯");
+}
+
+}  // namespace ftxui

src/ftxui/component/hoverable.cpp

@@ -49,8 +49,8 @@ Component Hoverable(Component component, bool* hover) {
     }
 
    private:
-    Element Render() override {
-      return ComponentBase::Render() | reflect(box_);
+    Element OnRender() override {
+      return ComponentBase::OnRender() | reflect(box_);
     }
 
     bool OnEvent(Event event) override {
@@ -98,8 +98,8 @@ Component Hoverable(Component component,
     }
 
    private:
-    Element Render() override {
-      return ComponentBase::Render() | reflect(box_);
+    Element OnRender() override {
+      return ComponentBase::OnRender() | reflect(box_);
     }
 
     bool OnEvent(Event event) override {

src/ftxui/component/input.cpp

@@ -96,9 +96,9 @@ class InputBase : public ComponentBase, public InputOption {
 
  private:
   // Component implementation:
-  Element Render() override {
+  Element OnRender() override {
     const bool is_focused = Focused();
-    const auto focused = (!is_focused && !hovered_) ? select
+    const auto focused = (!is_focused && !hovered_) ? nothing
                          : insert()                 ? focusCursorBarBlinking
                                                     : focusCursorBlockBlinking;
 
@@ -108,15 +108,12 @@ class InputBase : public ComponentBase, public InputOption {
     // placeholder.
     if (content->empty()) {
       auto element = text(placeholder()) | xflex | frame;
-      if (is_focused) {
-        element |= focus;
-      }
 
       return transform_func({
                  std::move(element), hovered_, is_focused,
                  true  // placeholder
              }) |
-             reflect(box_);
+             focus | reflect(box_);
     }
 
     Elements elements;
@@ -176,7 +173,7 @@ class InputBase : public ComponentBase, public InputOption {
       elements.push_back(element);
     }
 
-    auto element = vbox(std::move(elements)) | frame;
+    auto element = vbox(std::move(elements), cursor_line) | frame;
     return transform_func({
                std::move(element), hovered_, is_focused,
                false  // placeholder

src/ftxui/component/maybe.cpp

@@ -24,8 +24,8 @@ Component Maybe(Component child, std::function<bool()> show) {
     explicit Impl(std::function<bool()> show) : show_(std::move(show)) {}
 
    private:
-    Element Render() override {
-      return show_() ? ComponentBase::Render() : std::make_unique<Node>();
+    Element OnRender() override {
+      return show_() ? ComponentBase::OnRender() : std::make_unique<Node>();
     }
     bool Focusable() const override {
       return show_() && ComponentBase::Focusable();

src/ftxui/component/menu.cpp

@@ -105,7 +105,7 @@ class MenuBase : public ComponentBase, public MenuOption {
     }
   }
 
-  Element Render() override {
+  Element OnRender() override {
     Clamp();
     UpdateAnimationTarget();
 
@@ -123,22 +123,18 @@ class MenuBase : public ComponentBase, public MenuOption {
       const bool is_selected = (selected() == i);
 
       const EntryState state = {
-          entries[i],
-          false,
-          is_selected,
-          is_focused,
+          entries[i], false, is_selected, is_focused, i,
       };
 
-      auto focus_management = (selected_focus_ != i) ? nothing
-                              : is_menu_focused      ? focus
-                                                     : select;
-
-      const Element element =
-          (entries_option.transform ? entries_option.transform
-                                    : DefaultOptionTransform)  //
+      Element element = (entries_option.transform ? entries_option.transform
+                                                  : DefaultOptionTransform)  //
           (state);
-      elements.push_back(element | AnimatedColorStyle(i) | reflect(boxes_[i]) |
-                         focus_management);
+      if (selected_focus_ == i) {
+        element |= focus;
+      }
+      element |= AnimatedColorStyle(i);
+      element |= reflect(boxes_[i]);
+      elements.push_back(element);
     }
     if (elements_postfix) {
       elements.push_back(elements_postfix());
@@ -148,8 +144,9 @@ class MenuBase : public ComponentBase, public MenuOption {
       std::reverse(elements.begin(), elements.end());
     }
 
-    const Element bar =
-        IsHorizontal() ? hbox(std::move(elements)) : vbox(std::move(elements));
+    const Element bar = IsHorizontal()
+                            ? hbox(std::move(elements), selected_focus_)
+                            : vbox(std::move(elements), selected_focus_);
 
     if (!underline.enabled) {
       return bar | reflect(box_);
@@ -621,23 +618,22 @@ Component MenuEntry(MenuEntryOption option) {
         : MenuEntryOption(std::move(option)) {}
 
    private:
-    Element Render() override {
-      const bool focused = Focused();
+    Element OnRender() override {
+      const bool is_focused = Focused();
       UpdateAnimationTarget();
 
-      const EntryState state = {
-          label(),
-          false,
-          hovered_,
-          focused,
+      const EntryState state{
+          label(), false, hovered_, is_focused, Index(),
       };
 
-      const Element element =
-          (transform ? transform : DefaultOptionTransform)  //
+      Element element = (transform ? transform : DefaultOptionTransform)  //
           (state);
 
-      auto focus_management = focused ? select : nothing;
-      return element | AnimatedColorStyle() | focus_management | reflect(box_);
+      if (is_focused) {
+        element |= focus;
+      }
+
+      return element | AnimatedColorStyle() | reflect(box_);
     }
 
     void UpdateAnimationTarget() {
@@ -698,7 +694,6 @@ Component MenuEntry(MenuEntryOption option) {
       animator_foreground_.OnAnimation(params);
     }
 
-    MenuEntryOption option_;
     Box box_;
     bool hovered_ = false;
 

src/ftxui/component/menu_test.cpp

@@ -226,5 +226,50 @@ TEST(MenuTest, AnimationsVertical) {
   }
 }
 
+TEST(MenuTest, EntryIndex) {
+  int selected = 0;
+  std::vector<std::string> entries = {"0", "1", "2"};
+
+  auto option = MenuOption::Vertical();
+  option.entries = &entries;
+  option.selected = &selected;
+  option.entries_option.transform = [&](const EntryState& state) {
+    int curidx = std::stoi(state.label);
+    EXPECT_EQ(state.index, curidx);
+    return text(state.label);
+  };
+  auto menu = Menu(option);
+  menu->OnEvent(Event::ArrowDown);
+  menu->OnEvent(Event::ArrowDown);
+  menu->OnEvent(Event::Return);
+  entries.resize(2);
+  (void)menu->Render();
+}
+
+TEST(MenuTest, MenuEntryIndex) {
+  int selected = 0;
+
+  MenuEntryOption option;
+  option.transform = [&](const EntryState& state) {
+    int curidx = std::stoi(state.label);
+    EXPECT_EQ(state.index, curidx);
+    return text(state.label);
+  };
+  auto menu = Container::Vertical(
+      {
+          MenuEntry("0", option),
+          MenuEntry("1", option),
+          MenuEntry("2", option),
+      },
+      &selected);
+
+  menu->OnEvent(Event::ArrowDown);
+  menu->OnEvent(Event::ArrowDown);
+  menu->OnEvent(Event::Return);
+  for (int index = 0; index < menu->ChildCount(); index++) {
+    EXPECT_EQ(menu->ChildAt(index)->Index(), index);
+  }
+}
+
 }  // namespace ftxui
 // NOLINTEND

src/ftxui/component/modal.cpp

@@ -26,7 +26,7 @@ Component Modal(Component main, Component modal, const bool* show_modal) {
     }
 
    private:
-    Element Render() override {
+    Element OnRender() override {
       selector_ = *show_modal_;
       auto document = main_->Render();
       if (*show_modal_) {

src/ftxui/component/radiobox.cpp

@@ -28,7 +28,7 @@ class RadioboxBase : public ComponentBase, public RadioboxOption {
       : RadioboxOption(option) {}
 
  private:
-  Element Render() override {
+  Element OnRender() override {
     Clamp();
     Elements elements;
     const bool is_menu_focused = Focused();
@@ -36,21 +36,17 @@ class RadioboxBase : public ComponentBase, public RadioboxOption {
     for (int i = 0; i < size(); ++i) {
       const bool is_focused = (focused_entry() == i) && is_menu_focused;
       const bool is_selected = (hovered_ == i);
-      auto focus_management = !is_selected      ? nothing
-                              : is_menu_focused ? focus
-                                                : select;
       auto state = EntryState{
-          entries[i],
-          selected() == i,
-          is_selected,
-          is_focused,
+          entries[i], selected() == i, is_selected, is_focused, i,
       };
       auto element =
           (transform ? transform : RadioboxOption::Simple().transform)(state);
-
-      elements.push_back(element | focus_management | reflect(boxes_[i]));
+      if (is_selected) {
+        element |= focus;
+      }
+      elements.push_back(element | reflect(boxes_[i]));
     }
-    return vbox(std::move(elements)) | reflect(box_);
+    return vbox(std::move(elements), hovered_) | reflect(box_);
   }
 
   // NOLINTNEXTLINE(readability-function-cognitive-complexity)

src/ftxui/component/renderer.cpp

@@ -31,7 +31,7 @@ Component Renderer(std::function<Element()> render) {
    public:
     explicit Impl(std::function<Element()> render)
         : render_(std::move(render)) {}
-    Element Render() override { return render_(); }
+    Element OnRender() override { return render_(); }
     std::function<Element()> render_;
   };
 
@@ -88,7 +88,7 @@ Component Renderer(std::function<Element(bool)> render) {
         : render_(std::move(render)) {}
 
    private:
-    Element Render() override { return render_(Focused()) | reflect(box_); }
+    Element OnRender() override { return render_(Focused()) | reflect(box_); }
     bool Focusable() const override { return true; }
     bool OnEvent(Event event) override {
       if (event.is_mouse() && box_.Contain(event.mouse().x, event.mouse().y)) {

src/ftxui/component/resizable_split.cpp

@@ -94,7 +94,7 @@ class ResizableSplitBase : public ComponentBase {
     return false;
   }
 
-  Element Render() final {
+  Element OnRender() final {
     switch (options_->direction()) {
       case Direction::Left:
         return RenderLeft();

src/ftxui/component/screen_interactive.cpp

@@ -576,6 +576,18 @@ void ScreenInteractive::ForceHandleCtrlZ(bool force) {
   force_handle_ctrl_z_ = force;
 }
 
+/// @brief Returns the content of the current selection
+std::string ScreenInteractive::GetSelection() {
+  if (!selection_) {
+    return "";
+  }
+  return selection_->GetParts();
+}
+
+void ScreenInteractive::SelectionChange(std::function<void()> callback) {
+  selection_on_change_ = std::move(callback);
+}
+
 /// @brief Return the currently active screen, or null if none.
 // static
 ScreenInteractive* ScreenInteractive::Active() {
@@ -751,6 +763,14 @@ void ScreenInteractive::RunOnce(Component component) {
     ExecuteSignalHandlers();
   }
   Draw(std::move(component));
+
+  if (selection_data_previous_ != selection_data_) {
+    selection_data_previous_ = selection_data_;
+    if (selection_on_change_) {
+      selection_on_change_();
+      Post(Event::Custom);
+    }
+  }
 }
 
 // private
@@ -781,7 +801,9 @@ void ScreenInteractive::HandleTask(Component component, Task& task) {
 
       arg.screen_ = this;
 
-      const bool handled = component->OnEvent(arg);
+      bool handled = component->OnEvent(arg);
+
+      handled = HandleSelection(handled, arg);
 
       if (arg == Event::CtrlC && (!handled || force_handle_ctrl_c_)) {
         RecordSignal(SIGABRT);
@@ -824,6 +846,59 @@ void ScreenInteractive::HandleTask(Component component, Task& task) {
   // clang-format on
 }
 
+// private
+bool ScreenInteractive::HandleSelection(bool handled, Event event) {
+  if (handled) {
+    selection_pending_ = nullptr;
+    selection_data_.empty = true;
+    selection_ = nullptr;
+    return true;
+  }
+
+  if (!event.is_mouse()) {
+    return false;
+  }
+
+  auto& mouse = event.mouse();
+  if (mouse.button != Mouse::Left) {
+    return false;
+  }
+
+  if (mouse.motion == Mouse::Pressed) {
+    selection_pending_ = CaptureMouse();
+    selection_data_.start_x = mouse.x;
+    selection_data_.start_y = mouse.y;
+    selection_data_.end_x = mouse.x;
+    selection_data_.end_y = mouse.y;
+    return false;
+  }
+
+  if (!selection_pending_) {
+    return false;
+  }
+
+  if (mouse.motion == Mouse::Moved) {
+    if ((mouse.x != selection_data_.end_x) ||
+        (mouse.y != selection_data_.end_y)) {
+      selection_data_.end_x = mouse.x;
+      selection_data_.end_y = mouse.y;
+      selection_data_.empty = false;
+    }
+
+    return true;
+  }
+
+  if (mouse.motion == Mouse::Released) {
+    selection_pending_ = nullptr;
+    selection_data_.end_x = mouse.x;
+    selection_data_.end_y = mouse.y;
+    selection_data_.empty = false;
+    return true;
+  }
+
+  return false;
+}
+
 // private
 // NOLINTNEXTLINE
 void ScreenInteractive::Draw(Component component) {
@@ -899,7 +974,12 @@ void ScreenInteractive::Draw(Component component) {
 #endif
   previous_frame_resized_ = resized;
 
-  Render(*this, document);
+  selection_ = selection_data_.empty
+                   ? std::make_unique<Selection>()
+                   : std::make_unique<Selection>(
+                         selection_data_.start_x, selection_data_.start_y,  //
+                         selection_data_.end_x, selection_data_.end_y);
+  Render(*this, document.get(), *selection_);
 
   // Set cursor position for user using tools to insert CJK characters.
   {
@@ -988,4 +1068,21 @@ void ScreenInteractive::Signal(int signal) {
 #endif
 }
 
+bool ScreenInteractive::SelectionData::operator==(
+    const ScreenInteractive::SelectionData& other) const {
+  if (empty && other.empty) {
+    return true;
+  }
+  if (empty || other.empty) {
+    return false;
+  }
+  return start_x == other.start_x && start_y == other.start_y &&
+         end_x == other.end_x && end_y == other.end_y;
+}
+
+bool ScreenInteractive::SelectionData::operator!=(
+    const ScreenInteractive::SelectionData& other) const {
+  return !(*this == other);
+}
+
 }  // namespace ftxui.

src/ftxui/component/slider.cpp

@@ -16,7 +16,6 @@
 #include "ftxui/dom/elements.hpp"  // for operator|, text, Element, xflex, hbox, color, underlined, reflect, Decorator, dim, vcenter, focus, nothing, select, yflex, gaugeDirection
 #include "ftxui/screen/box.hpp"    // for Box
 #include "ftxui/screen/color.hpp"  // for Color, Color::GrayDark, Color::White
-#include "ftxui/screen/util.hpp"   // for clamp
 #include "ftxui/util/ref.hpp"      // for ConstRef, Ref, ConstStringRef
 
 namespace ftxui {
@@ -39,7 +38,7 @@ class SliderBase : public SliderOption<T>, public ComponentBase {
  public:
   explicit SliderBase(SliderOption<T> options) : SliderOption<T>(options) {}
 
-  Element Render() override {
+  Element OnRender() override {
     auto gauge_color =
         Focused() ? color(this->color_active) : color(this->color_inactive);
     const float percent =
@@ -134,53 +133,52 @@ class SliderBase : public SliderOption<T>, public ComponentBase {
     return ComponentBase::OnEvent(event);
   }
 
+  bool OnCapturedMouseEvent(Event event) {
+    if (event.mouse().motion == Mouse::Released) {
+      captured_mouse_ = nullptr;
+      return true;
+    }
+
+    T old_value = this->value();
+    switch (this->direction) {
+      case Direction::Right: {
+        this->value() = this->min() + (event.mouse().x - gauge_box_.x_min) *
+                                          (this->max() - this->min()) /
+                                          (gauge_box_.x_max - gauge_box_.x_min);
+
+        break;
+      }
+      case Direction::Left: {
+        this->value() = this->max() - (event.mouse().x - gauge_box_.x_min) *
+                                          (this->max() - this->min()) /
+                                          (gauge_box_.x_max - gauge_box_.x_min);
+        break;
+      }
+      case Direction::Down: {
+        this->value() = this->min() + (event.mouse().y - gauge_box_.y_min) *
+                                          (this->max() - this->min()) /
+                                          (gauge_box_.y_max - gauge_box_.y_min);
+        break;
+      }
+      case Direction::Up: {
+        this->value() = this->max() - (event.mouse().y - gauge_box_.y_min) *
+                                          (this->max() - this->min()) /
+                                          (gauge_box_.y_max - gauge_box_.y_min);
+        break;
+      }
+    }
+
+    this->value() = std::max(this->min(), std::min(this->max(), this->value()));
+
+    if (old_value != this->value() && this->on_change) {
+      this->on_change();
+    }
+    return true;
+  }
+
   bool OnMouseEvent(Event event) {
     if (captured_mouse_) {
-      if (event.mouse().motion == Mouse::Released) {
-        captured_mouse_ = nullptr;
-        return true;
-      }
-
-      T old_value = this->value();
-      switch (this->direction) {
-        case Direction::Right: {
-          this->value() =
-              this->min() + (event.mouse().x - gauge_box_.x_min) *
-                                (this->max() - this->min()) /
-                                (gauge_box_.x_max - gauge_box_.x_min);
-
-          break;
-        }
-        case Direction::Left: {
-          this->value() =
-              this->max() - (event.mouse().x - gauge_box_.x_min) *
-                                (this->max() - this->min()) /
-                                (gauge_box_.x_max - gauge_box_.x_min);
-          break;
-        }
-        case Direction::Down: {
-          this->value() =
-              this->min() + (event.mouse().y - gauge_box_.y_min) *
-                                (this->max() - this->min()) /
-                                (gauge_box_.y_max - gauge_box_.y_min);
-          break;
-        }
-        case Direction::Up: {
-          this->value() =
-              this->max() - (event.mouse().y - gauge_box_.y_min) *
-                                (this->max() - this->min()) /
-                                (gauge_box_.y_max - gauge_box_.y_min);
-          break;
-        }
-      }
-
-      this->value() =
-          std::max(this->min(), std::min(this->max(), this->value()));
-
-      if (old_value != this->value() && this->on_change) {
-        this->on_change();
-      }
-      return true;
+      return OnCapturedMouseEvent(event);
     }
 
     if (event.mouse().button != Mouse::Left) {
@@ -198,7 +196,7 @@ class SliderBase : public SliderOption<T>, public ComponentBase {
 
     if (captured_mouse_) {
       TakeFocus();
-      return true;
+      return OnCapturedMouseEvent(event);
     }
 
     return false;
@@ -242,19 +240,21 @@ class SliderWithLabel : public ComponentBase {
     return true;
   }
 
-  Element Render() override {
-    auto focus_management = Focused() ? focus : Active() ? select : nothing;
+  Element OnRender() override {
     auto gauge_color = (Focused() || mouse_hover_) ? color(Color::White)
                                                    : color(Color::GrayDark);
-    return hbox({
-               text(label_()) | dim | vcenter,
-               hbox({
-                   text("["),
-                   ComponentBase::Render() | underlined,
-                   text("]"),
-               }) | xflex,
-           }) |
-           gauge_color | xflex | reflect(box_) | focus_management;
+    auto element = hbox({
+                       text(label_()) | dim | vcenter,
+                       hbox({
+                           text("["),
+                           ComponentBase::Render() | underlined,
+                           text("]"),
+                       }) | xflex,
+                   }) |
+                   gauge_color | xflex | reflect(box_);
+
+    element |= focus;
+    return element;
   }
 
   ConstStringRef label_;

src/ftxui/component/slider_test.cpp

@@ -60,17 +60,17 @@ TEST(SliderTest, Right) {
   EXPECT_EQ(value, 50);
   EXPECT_EQ(updated, 0);
   EXPECT_TRUE(slider->OnEvent(MousePressed(3, 0)));
-  EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 0);
+  EXPECT_EQ(value, 30);
+  EXPECT_EQ(updated, 1);
   EXPECT_TRUE(slider->OnEvent(MousePressed(9, 0)));
   EXPECT_EQ(value, 90);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(9, 2)));
   EXPECT_EQ(value, 90);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(5, 2)));
   EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 2);
+  EXPECT_EQ(updated, 3);
   EXPECT_TRUE(slider->OnEvent(MouseReleased(5, 2)));
   EXPECT_FALSE(slider->OnEvent(MousePressed(5, 2)));
   EXPECT_EQ(value, 50);
@@ -92,17 +92,17 @@ TEST(SliderTest, Left) {
   EXPECT_EQ(value, 50);
   EXPECT_EQ(updated, 0);
   EXPECT_TRUE(slider->OnEvent(MousePressed(3, 0)));
-  EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 0);
+  EXPECT_EQ(value, 70);
+  EXPECT_EQ(updated, 1);
   EXPECT_TRUE(slider->OnEvent(MousePressed(9, 0)));
   EXPECT_EQ(value, 10);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(9, 2)));
   EXPECT_EQ(value, 10);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(5, 2)));
   EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 2);
+  EXPECT_EQ(updated, 3);
   EXPECT_TRUE(slider->OnEvent(MouseReleased(5, 2)));
   EXPECT_FALSE(slider->OnEvent(MousePressed(5, 2)));
   EXPECT_EQ(value, 50);
@@ -124,21 +124,21 @@ TEST(SliderTest, Down) {
   EXPECT_EQ(value, 50);
   EXPECT_EQ(updated, 0);
   EXPECT_TRUE(slider->OnEvent(MousePressed(0, 3)));
-  EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 0);
+  EXPECT_EQ(value, 30);
+  EXPECT_EQ(updated, 1);
   EXPECT_TRUE(slider->OnEvent(MousePressed(0, 9)));
   EXPECT_EQ(value, 90);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(2, 9)));
   EXPECT_EQ(value, 90);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(2, 5)));
   EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 2);
+  EXPECT_EQ(updated, 3);
   EXPECT_TRUE(slider->OnEvent(MouseReleased(2, 5)));
   EXPECT_FALSE(slider->OnEvent(MousePressed(2, 5)));
   EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 2);
+  EXPECT_EQ(updated, 3);
 }
 
 TEST(SliderTest, Up) {
@@ -157,17 +157,17 @@ TEST(SliderTest, Up) {
   EXPECT_EQ(value, 50);
   EXPECT_EQ(updated, 0);
   EXPECT_TRUE(slider->OnEvent(MousePressed(0, 3)));
-  EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 0);
+  EXPECT_EQ(value, 70);
+  EXPECT_EQ(updated, 1);
   EXPECT_TRUE(slider->OnEvent(MousePressed(0, 9)));
   EXPECT_EQ(value, 10);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(2, 9)));
   EXPECT_EQ(value, 10);
-  EXPECT_EQ(updated, 1);
+  EXPECT_EQ(updated, 2);
   EXPECT_TRUE(slider->OnEvent(MousePressed(2, 5)));
   EXPECT_EQ(value, 50);
-  EXPECT_EQ(updated, 2);
+  EXPECT_EQ(updated, 3);
   EXPECT_TRUE(slider->OnEvent(MouseReleased(2, 5)));
   EXPECT_FALSE(slider->OnEvent(MousePressed(2, 5)));
   EXPECT_EQ(value, 50);

src/ftxui/component/window.cpp

@@ -93,7 +93,7 @@ class ResizeDecorator : public NodeDecorator {
 
 Element DefaultRenderState(const WindowRenderState& state) {
   Element element = state.inner;
-  if (state.active) {
+  if (!state.active) {
     element |= dim;
   }
 
@@ -124,7 +124,7 @@ class WindowImpl : public ComponentBase, public WindowOptions {
   }
 
  private:
-  Element Render() final {
+  Element OnRender() final {
     auto element = ComponentBase::Render();
 
     const bool captureable =

src/ftxui/dom/border.cpp

@@ -54,10 +54,10 @@ class Border : public Node {
       requirement_.min_x =
           std::max(requirement_.min_x, children_[1]->requirement().min_x + 2);
     }
-    requirement_.selected_box.x_min++;
-    requirement_.selected_box.x_max++;
-    requirement_.selected_box.y_min++;
-    requirement_.selected_box.y_max++;
+    requirement_.focused.box.x_min++;
+    requirement_.focused.box.x_max++;
+    requirement_.focused.box.y_min++;
+    requirement_.focused.box.y_max++;
   }
 
   void SetBox(Box box) override {
@@ -65,7 +65,8 @@ class Border : public Node {
     if (children_.size() == 2) {
       Box title_box;
       title_box.x_min = box.x_min + 1;
-      title_box.x_max = std::min(box.x_max - 1, box.x_min + children_[1]->requirement().min_x);
+      title_box.x_max = std::min(box.x_max - 1,
+                                 box.x_min + children_[1]->requirement().min_x);
       title_box.y_min = box.y_min;
       title_box.y_max = box.y_min;
       children_[1]->SetBox(title_box);
@@ -145,10 +146,8 @@ class BorderPixel : public Node {
       requirement_.min_x =
           std::max(requirement_.min_x, children_[1]->requirement().min_x + 2);
     }
-    requirement_.selected_box.x_min++;
-    requirement_.selected_box.x_max++;
-    requirement_.selected_box.y_min++;
-    requirement_.selected_box.y_max++;
+
+    requirement_.focused.box.Shift(1, 1);
   }
 
   void SetBox(Box box) override {

src/ftxui/dom/box_helper.hpp

@@ -5,6 +5,7 @@
 #define FTXUI_DOM_BOX_HELPER_HPP
 
 #include <vector>
+#include "ftxui/dom/requirement.hpp"
 
 namespace ftxui::box_helper {
 
@@ -19,7 +20,6 @@ struct Element {
 };
 
 void Compute(std::vector<Element>* elements, int target_size);
-
 }  // namespace ftxui::box_helper
 
 #endif /* end of include guard: FTXUI_DOM_BOX_HELPER_HPP */

src/ftxui/dom/dbox.cpp

@@ -21,24 +21,20 @@ class DBox : public Node {
   explicit DBox(Elements children) : Node(std::move(children)) {}
 
   void ComputeRequirement() override {
-    requirement_.min_x = 0;
-    requirement_.min_y = 0;
-    requirement_.flex_grow_x = 0;
-    requirement_.flex_grow_y = 0;
-    requirement_.flex_shrink_x = 0;
-    requirement_.flex_shrink_y = 0;
-    requirement_.selection = Requirement::NORMAL;
+    requirement_ = Requirement{};
     for (auto& child : children_) {
       child->ComputeRequirement();
+
+      // Propagate the focused requirement.
+      if (requirement_.focused.Prefer(child->requirement().focused)) {
+        requirement_.focused = child->requirement().focused;
+      }
+
+      // Extend the min_x and min_y to contain all the children
       requirement_.min_x =
           std::max(requirement_.min_x, child->requirement().min_x);
       requirement_.min_y =
           std::max(requirement_.min_y, child->requirement().min_y);
-
-      if (requirement_.selection < child->requirement().selection) {
-        requirement_.selection = child->requirement().selection;
-        requirement_.selected_box = child->requirement().selected_box;
-      }
     }
   }
 
@@ -79,6 +75,7 @@ class DBox : public Node {
             acc->bold = pixel.bold;
             acc->dim = pixel.dim;
             acc->inverted = pixel.inverted;
+            acc->italic = pixel.italic;
             acc->underlined = pixel.underlined;
             acc->underlined_double = pixel.underlined_double;
             acc->strikethrough = pixel.strikethrough;

src/ftxui/dom/flex.cpp

@@ -80,6 +80,7 @@ class Flex : public Node {
   }
 
   void SetBox(Box box) override {
+    Node::SetBox(box);
     if (children_.empty()) {
       return;
     }

src/ftxui/dom/flexbox.cpp

@@ -4,6 +4,7 @@
 #include <algorithm>  // for min, max
 #include <cstddef>    // for size_t
 #include <memory>  // for __shared_ptr_access, shared_ptr, allocator_traits<>::value_type, make_shared
+#include <tuple>   // for ignore
 #include <utility>  // for move, swap
 #include <vector>   // for vector
 
@@ -12,6 +13,7 @@
 #include "ftxui/dom/flexbox_helper.hpp"  // for Block, Global, Compute
 #include "ftxui/dom/node.hpp"            // for Node, Elements, Node::Status
 #include "ftxui/dom/requirement.hpp"     // for Requirement
+#include "ftxui/dom/selection.hpp"       // for Selection
 #include "ftxui/screen/box.hpp"          // for Box
 
 namespace ftxui {
@@ -89,37 +91,32 @@ class Flexbox : public Node {
   }
 
   void ComputeRequirement() override {
+    requirement_ = Requirement{};
     for (auto& child : children_) {
       child->ComputeRequirement();
     }
-    flexbox_helper::Global global;
-    global.config = config_normalized_;
+    global_ = flexbox_helper::Global();
+    global_.config = config_normalized_;
     if (IsColumnOriented()) {
-      global.size_x = 100000;  // NOLINT
-      global.size_y = asked_;
+      global_.size_x = 100000;  // NOLINT
+      global_.size_y = asked_;
     } else {
-      global.size_x = asked_;
-      global.size_y = 100000;  // NOLINT
+      global_.size_x = asked_;
+      global_.size_y = 100000;  // NOLINT
     }
-    Layout(global, true);
+    Layout(global_, true);
 
-    // Reset:
-    requirement_.selection = Requirement::Selection::NORMAL;
-    requirement_.selected_box = Box();
-    requirement_.min_x = 0;
-    requirement_.min_y = 0;
-
-    if (global.blocks.empty()) {
+    if (global_.blocks.empty()) {
       return;
     }
 
     // Compute the union of all the blocks:
     Box box;
-    box.x_min = global.blocks[0].x;
-    box.y_min = global.blocks[0].y;
-    box.x_max = global.blocks[0].x + global.blocks[0].dim_x;
-    box.y_max = global.blocks[0].y + global.blocks[0].dim_y;
-    for (auto& b : global.blocks) {
+    box.x_min = global_.blocks[0].x;
+    box.y_min = global_.blocks[0].y;
+    box.x_max = global_.blocks[0].x + global_.blocks[0].dim_x;
+    box.y_max = global_.blocks[0].y + global_.blocks[0].dim_y;
+    for (auto& b : global_.blocks) {
       box.x_min = std::min(box.x_min, b.x);
       box.y_min = std::min(box.y_min, b.y);
       box.x_max = std::max(box.x_max, b.x + b.dim_x);
@@ -130,19 +127,14 @@ class Flexbox : public Node {
 
     // Find the selection:
     for (size_t i = 0; i < children_.size(); ++i) {
-      if (requirement_.selection >= children_[i]->requirement().selection) {
-        continue;
+      if (requirement_.focused.Prefer(children_[i]->requirement().focused)) {
+        requirement_.focused = children_[i]->requirement().focused;
+        // Shift |focused.box| according to its position inside this component:
+        auto& b = global_.blocks[i];
+        requirement_.focused.box.Shift(b.x, b.y);
+        requirement_.focused.box =
+            Box::Intersection(requirement_.focused.box, box);
       }
-      requirement_.selection = children_[i]->requirement().selection;
-      Box selected_box = children_[i]->requirement().selected_box;
-
-      // Shift |selected_box| according to its position inside this component:
-      auto& b = global.blocks[i];
-      selected_box.x_min += b.x;
-      selected_box.y_min += b.y;
-      selected_box.x_max += b.x;
-      selected_box.y_max += b.y;
-      requirement_.selected_box = Box::Intersection(selected_box, box);
     }
   }
 
@@ -177,6 +169,43 @@ class Flexbox : public Node {
     }
   }
 
+  void Select(Selection& selection) override {
+    // If this Node box_ doesn't intersect with the selection, then no
+    // selection.
+    if (Box::Intersection(selection.GetBox(), box_).IsEmpty()) {
+      return;
+    }
+
+    Selection selection_lines = IsColumnOriented()
+                                    ? selection.SaturateVertical(box_)
+                                    : selection.SaturateHorizontal(box_);
+
+    size_t i = 0;
+    for (auto& line : global_.lines) {
+      Box box;
+      box.x_min = box_.x_min + line.x;
+      box.x_max = box_.x_min + line.x + line.dim_x - 1;
+      box.y_min = box_.y_min + line.y;
+      box.y_max = box_.y_min + line.y + line.dim_y - 1;
+
+      // If the line box doesn't intersect with the selection, then no
+      // selection.
+      if (Box::Intersection(selection.GetBox(), box).IsEmpty()) {
+        continue;
+      }
+
+      Selection selection_line = IsColumnOriented()
+                                     ? selection_lines.SaturateHorizontal(box)
+                                     : selection_lines.SaturateVertical(box);
+
+      for (auto& block : line.blocks) {
+        std::ignore = block;
+        children_[i]->Select(selection_line);
+        i++;
+      }
+    }
+  }
+
   void Check(Status* status) override {
     for (auto& child : children_) {
       child->Check(status);
@@ -194,6 +223,7 @@ class Flexbox : public Node {
   bool need_iteration_ = true;
   const FlexboxConfig config_;
   const FlexboxConfig config_normalized_;
+  flexbox_helper::Global global_;
 };
 
 }  // namespace

src/ftxui/dom/flexbox_helper.cpp

@@ -68,6 +68,10 @@ void SymmetryXY(Global& g) {
     std::swap(b.x, b.y);
     std::swap(b.dim_x, b.dim_y);
   }
+  for (auto& l : g.lines) {
+    std::swap(l.x, l.y);
+    std::swap(l.dim_x, l.dim_y);
+  }
 }
 
 void SymmetryX(Global& g) {
@@ -75,6 +79,9 @@ void SymmetryX(Global& g) {
   for (auto& b : g.blocks) {
     b.x = g.size_x - b.x - b.dim_x;
   }
+  for (auto& l : g.lines) {
+    l.x = g.size_x - l.x - l.dim_x;
+  }
 }
 
 void SymmetryY(Global& g) {
@@ -82,14 +89,13 @@ void SymmetryY(Global& g) {
   for (auto& b : g.blocks) {
     b.y = g.size_y - b.y - b.dim_y;
   }
+  for (auto& l : g.lines) {
+    l.y = g.size_y - l.y - l.dim_y;
+  }
 }
 
-struct Line {
-  std::vector<Block*> blocks;
-};
-
-void SetX(Global& global, std::vector<Line> lines) {
-  for (auto& line : lines) {
+void SetX(Global& global) {
+  for (auto& line : global.lines) {
     std::vector<box_helper::Element> elements;
     elements.reserve(line.blocks.size());
     for (auto* block : line.blocks) {
@@ -110,19 +116,24 @@ void SetX(Global& global, std::vector<Line> lines) {
 
     int x = 0;
     for (size_t i = 0; i < line.blocks.size(); ++i) {
-      line.blocks[i]->dim_x = elements[i].size;
       line.blocks[i]->x = x;
+      line.blocks[i]->dim_x = elements[i].size;
       x += elements[i].size;
       x += global.config.gap_x;
     }
   }
+
+  for (auto& line : global.lines) {
+    line.x = 0;
+    line.dim_x = global.size_x;
+  }
 }
 
 // NOLINTNEXTLINE(readability-function-cognitive-complexity)
-void SetY(Global& g, std::vector<Line> lines) {
+void SetY(Global& g) {
   std::vector<box_helper::Element> elements;
-  elements.reserve(lines.size());
-  for (auto& line : lines) {
+  elements.reserve(g.lines.size());
+  for (auto& line : g.lines) {
     box_helper::Element element;
     element.flex_shrink = line.blocks.front()->flex_shrink_y;
     element.flex_grow = line.blocks.front()->flex_grow_y;
@@ -202,9 +213,9 @@ void SetY(Global& g, std::vector<Line> lines) {
   }
 
   // [Align items]
-  for (size_t i = 0; i < lines.size(); ++i) {
+  for (size_t i = 0; i < g.lines.size(); ++i) {
     auto& element = elements[i];
-    for (auto* block : lines[i].blocks) {
+    for (auto* block : g.lines[i].blocks) {
       const bool stretch =
           block->flex_grow_y != 0 ||
           g.config.align_content == FlexboxConfig::AlignContent::Stretch;
@@ -237,10 +248,16 @@ void SetY(Global& g, std::vector<Line> lines) {
       }
     }
   }
+
+  ys.push_back(g.size_y);
+  for (size_t i = 0; i < g.lines.size(); ++i) {
+    g.lines[i].y = ys[i];
+    g.lines[i].dim_y = ys[i + 1] - ys[i];
+  }
 }
 
-void JustifyContent(Global& g, std::vector<Line> lines) {
-  for (auto& line : lines) {
+void JustifyContent(Global& g) {
+  for (auto& line : g.lines) {
     Block* last = line.blocks.back();
     int remaining_space = g.size_x - last->x - last->dim_x;
     switch (g.config.justify_content) {
@@ -315,38 +332,36 @@ void Compute2(Global& global) {
 
 void Compute3(Global& global) {
   // Step 1: Lay out every elements into rows:
-  std::vector<Line> lines;
   {
     Line line;
     int x = 0;
-    line.blocks.reserve(global.blocks.size());
     for (auto& block : global.blocks) {
       // Does it fit the end of the row?
       // No? Then we need to start a new one:
       if (x + block.min_size_x > global.size_x) {
         x = 0;
         if (!line.blocks.empty()) {
-          lines.push_back(std::move(line));
+          global.lines.push_back(std::move(line));
         }
         line = Line();
       }
 
-      block.line = static_cast<int>(lines.size());
+      block.line = static_cast<int>(global.lines.size());
       block.line_position = static_cast<int>(line.blocks.size());
       line.blocks.push_back(&block);
       x += block.min_size_x + global.config.gap_x;
     }
     if (!line.blocks.empty()) {
-      lines.push_back(std::move(line));
+      global.lines.push_back(std::move(line));
     }
   }
 
   // Step 2: Set positions on the X axis.
-  SetX(global, lines);
-  JustifyContent(global, lines);  // Distribute remaining space.
+  SetX(global);
+  JustifyContent(global);  // Distribute remaining space.
 
   // Step 3: Set positions on the Y axis.
-  SetY(global, lines);
+  SetY(global);
 }
 
 }  // namespace

src/ftxui/dom/flexbox_helper.hpp

@@ -9,6 +9,7 @@
 
 namespace ftxui::flexbox_helper {
 
+// A block is a rectangle in the flexbox.
 struct Block {
   // Input:
   int min_size_x = 0;
@@ -28,8 +29,18 @@ struct Block {
   bool overflow = false;
 };
 
+// A line is a row of blocks.
+struct Line {
+  std::vector<Block*> blocks;
+  int x = 0;
+  int y = 0;
+  int dim_x = 0;
+  int dim_y = 0;
+};
+
 struct Global {
   std::vector<Block> blocks;
+  std::vector<Line> lines;
   FlexboxConfig config;
   int size_x;
   int size_y;

src/ftxui/dom/focus.cpp

@@ -36,13 +36,12 @@ Decorator focusPositionRelative(float x, float y) {
 
     void ComputeRequirement() override {
       NodeDecorator::ComputeRequirement();
-      requirement_.selection = Requirement::Selection::NORMAL;
-
-      Box& box = requirement_.selected_box;
-      box.x_min = int(float(requirement_.min_x) * x_);
-      box.y_min = int(float(requirement_.min_y) * y_);
-      box.x_max = int(float(requirement_.min_x) * x_);
-      box.y_max = int(float(requirement_.min_y) * y_);
+      requirement_.focused.enabled = true;
+      requirement_.focused.node = this;
+      requirement_.focused.box.x_min = int(float(requirement_.min_x) * x_);
+      requirement_.focused.box.y_min = int(float(requirement_.min_y) * y_);
+      requirement_.focused.box.x_max = int(float(requirement_.min_x) * x_);
+      requirement_.focused.box.y_max = int(float(requirement_.min_y) * y_);
     }
 
    private:
@@ -75,9 +74,9 @@ Decorator focusPosition(int x, int y) {
 
     void ComputeRequirement() override {
       NodeDecorator::ComputeRequirement();
-      requirement_.selection = Requirement::Selection::NORMAL;
+      requirement_.focused.enabled = false;
 
-      Box& box = requirement_.selected_box;
+      Box& box = requirement_.focused.box;
       box.x_min = x_;
       box.y_min = y_;
       box.x_max = x_;

src/ftxui/dom/frame.cpp

@@ -6,28 +6,28 @@
 #include <utility>    // for move
 
 #include "ftxui/dom/elements.hpp"  // for Element, unpack, Elements, focus, frame, select, xframe, yframe
-#include "ftxui/dom/node.hpp"  // for Node, Elements
-#include "ftxui/dom/requirement.hpp"  // for Requirement, Requirement::FOCUSED, Requirement::SELECTED
-#include "ftxui/screen/box.hpp"      // for Box
-#include "ftxui/screen/screen.hpp"   // for Screen, Screen::Cursor
-#include "ftxui/util/autoreset.hpp"  // for AutoReset
+#include "ftxui/dom/node.hpp"         // for Node, Elements
+#include "ftxui/dom/requirement.hpp"  // for Requirement
+#include "ftxui/screen/box.hpp"       // for Box
+#include "ftxui/screen/screen.hpp"    // for Screen, Screen::Cursor
+#include "ftxui/util/autoreset.hpp"   // for AutoReset
 
 namespace ftxui {
 
 namespace {
-class Select : public Node {
+class Focus : public Node {
  public:
-  explicit Select(Elements children) : Node(std::move(children)) {}
+  explicit Focus(Elements children) : Node(std::move(children)) {}
 
   void ComputeRequirement() override {
     Node::ComputeRequirement();
     requirement_ = children_[0]->requirement();
-    auto& selected_box = requirement_.selected_box;
-    selected_box.x_min = 0;
-    selected_box.y_min = 0;
-    selected_box.x_max = requirement_.min_x - 1;
-    selected_box.y_max = requirement_.min_y - 1;
-    requirement_.selection = Requirement::SELECTED;
+    requirement_.focused.enabled = true;
+    requirement_.focused.node = this;
+    requirement_.focused.box.x_min = 0;
+    requirement_.focused.box.y_min = 0;
+    requirement_.focused.box.x_max = requirement_.min_x - 1;
+    requirement_.focused.box.y_max = requirement_.min_y - 1;
   }
 
   void SetBox(Box box) override {
@@ -36,65 +36,21 @@ class Select : public Node {
   }
 };
 
-class Focus : public Select {
- public:
-  using Select::Select;
-
-  void ComputeRequirement() override {
-    Select::ComputeRequirement();
-    requirement_.selection = Requirement::FOCUSED;
-  }
-
-  void Render(Screen& screen) override {
-    Select::Render(screen);
-
-    // Setting the cursor to the right position allow folks using CJK (China,
-    // Japanese, Korean, ...) characters to see their [input method editor]
-    // displayed at the right location. See [issue].
-    //
-    // [input method editor]:
-    // https://en.wikipedia.org/wiki/Input_method
-    //
-    // [issue]:
-    // https://github.com/ArthurSonzogni/FTXUI/issues/2#issuecomment-505282355
-    //
-    // Unfortunately, Microsoft terminal do not handle properly hidding the
-    // cursor. Instead the character under the cursor is hidden, which is a big
-    // problem. As a result, we can't enable setting cursor to the right
-    // location. It will be displayed at the bottom right corner.
-    // See:
-    // https://github.com/microsoft/terminal/issues/1203
-    // https://github.com/microsoft/terminal/issues/3093
-#if !defined(FTXUI_MICROSOFT_TERMINAL_FALLBACK)
-    screen.SetCursor(Screen::Cursor{
-        box_.x_min,
-        box_.y_min,
-        Screen::Cursor::Shape::Hidden,
-    });
-#endif
-  }
-};
-
 class Frame : public Node {
  public:
   Frame(Elements children, bool x_frame, bool y_frame)
       : Node(std::move(children)), x_frame_(x_frame), y_frame_(y_frame) {}
 
-  void ComputeRequirement() override {
-    Node::ComputeRequirement();
-    requirement_ = children_[0]->requirement();
-  }
-
   void SetBox(Box box) override {
     Node::SetBox(box);
-    auto& selected_box = requirement_.selected_box;
+    auto& focused_box = requirement_.focused.box;
     Box children_box = box;
 
     if (x_frame_) {
       const int external_dimx = box.x_max - box.x_min;
       const int internal_dimx = std::max(requirement_.min_x, external_dimx);
-      const int focused_dimx = selected_box.x_max - selected_box.x_min;
-      int dx = selected_box.x_min - external_dimx / 2 + focused_dimx / 2;
+      const int focused_dimx = focused_box.x_max - focused_box.x_min;
+      int dx = focused_box.x_min - external_dimx / 2 + focused_dimx / 2;
       dx = std::max(0, std::min(internal_dimx - external_dimx - 1, dx));
       children_box.x_min = box.x_min - dx;
       children_box.x_max = box.x_min + internal_dimx - dx;
@@ -103,8 +59,8 @@ class Frame : public Node {
     if (y_frame_) {
       const int external_dimy = box.y_max - box.y_min;
       const int internal_dimy = std::max(requirement_.min_y, external_dimy);
-      const int focused_dimy = selected_box.y_max - selected_box.y_min;
-      int dy = selected_box.y_min - external_dimy / 2 + focused_dimy / 2;
+      const int focused_dimy = focused_box.y_max - focused_box.y_min;
+      int dy = focused_box.y_min - external_dimy / 2 + focused_dimy / 2;
       dy = std::max(0, std::min(internal_dimy - external_dimy - 1, dy));
       children_box.y_min = box.y_min - dy;
       children_box.y_max = box.y_min + internal_dimy - dy;
@@ -130,33 +86,29 @@ class FocusCursor : public Focus {
       : Focus(std::move(children)), shape_(shape) {}
 
  private:
-  void Render(Screen& screen) override {
-    Select::Render(screen);  // NOLINT
-    screen.SetCursor(Screen::Cursor{
-        box_.x_min,
-        box_.y_min,
-        shape_,
-    });
+  void ComputeRequirement() override {
+    Focus::ComputeRequirement();  // NOLINT
+    requirement_.focused.cursor_shape = shape_;
   }
   Screen::Cursor::Shape shape_;
 };
 
 }  // namespace
 
-/// @brief Set the `child` to be the one selected among its siblings.
-/// @param child The element to be selected.
-/// @ingroup dom
-Element select(Element child) {
-  return std::make_shared<Select>(unpack(std::move(child)));
-}
-
-/// @brief Set the `child` to be the one in focus globally.
+/// @brief Set the `child` to be the one focused among its siblings.
 /// @param child The element to be focused.
 /// @ingroup dom
 Element focus(Element child) {
   return std::make_shared<Focus>(unpack(std::move(child)));
 }
 
+/// This is deprecated. Use `focus` instead.
+/// @brief Set the `child` to be the one focused among its siblings.
+/// @param child The element to be focused.
+Element select(Element child) {
+  return focus(std::move(child));
+}
+
 /// @brief Allow an element to be displayed inside a 'virtual' area. It size can
 /// be larger than its container. In this case only a smaller portion is
 /// displayed. The view is scrollable to make the focused element visible.

src/ftxui/dom/gridbox.cpp

@@ -49,13 +49,7 @@ class GridBox : public Node {
   }
 
   void ComputeRequirement() override {
-    requirement_.min_x = 0;
-    requirement_.min_y = 0;
-    requirement_.flex_grow_x = 0;
-    requirement_.flex_grow_y = 0;
-    requirement_.flex_shrink_x = 0;
-    requirement_.flex_shrink_y = 0;
-
+    requirement_ = Requirement{};
     for (auto& line : lines_) {
       for (auto& cell : line) {
         cell->ComputeRequirement();
@@ -75,19 +69,15 @@ class GridBox : public Node {
     requirement_.min_x = Integrate(size_x);
     requirement_.min_y = Integrate(size_y);
 
-    // Forward the selected/focused child state:
-    requirement_.selection = Requirement::NORMAL;
+    // Forward the focused/focused child state:
     for (int x = 0; x < x_size; ++x) {
       for (int y = 0; y < y_size; ++y) {
-        if (requirement_.selection >= lines_[y][x]->requirement().selection) {
+        if (requirement_.focused.enabled ||
+            !lines_[y][x]->requirement().focused.enabled) {
           continue;
         }
-        requirement_.selection = lines_[y][x]->requirement().selection;
-        requirement_.selected_box = lines_[y][x]->requirement().selected_box;
-        requirement_.selected_box.x_min += size_x[x];
-        requirement_.selected_box.x_max += size_x[x];
-        requirement_.selected_box.y_min += size_y[y];
-        requirement_.selected_box.y_max += size_y[y];
+        requirement_.focused = lines_[y][x]->requirement().focused;
+        requirement_.focused.box.Shift(size_x[x], size_y[y]);
       }
     }
   }

src/ftxui/dom/gridbox_test.cpp

@@ -7,7 +7,7 @@
 #include <string>     // for allocator, basic_string, string
 #include <vector>     // for vector
 
-#include "ftxui/dom/elements.hpp"  // for text, operator|, Element, flex, Elements, flex_grow, flex_shrink, vtext, gridbox, vbox, focus, operator|=, border, frame
+#include "ftxui/dom/elements.hpp"  // for text, operator|, Element, flex, Elements, flex_grow, flex_shrink, vtext, gridbox, vbox, select, operator|=, border, frame
 #include "ftxui/dom/node.hpp"      // for Render
 #include "ftxui/screen/screen.hpp"  // for Screen
 

src/ftxui/dom/hbox.cpp

@@ -11,8 +11,8 @@
 #include "ftxui/dom/elements.hpp"     // for Element, Elements, hbox
 #include "ftxui/dom/node.hpp"         // for Node, Elements
 #include "ftxui/dom/requirement.hpp"  // for Requirement
+#include "ftxui/dom/selection.hpp"    // for Selection
 #include "ftxui/screen/box.hpp"       // for Box
-
 namespace ftxui {
 
 namespace {
@@ -20,22 +20,20 @@ class HBox : public Node {
  public:
   explicit HBox(Elements children) : Node(std::move(children)) {}
 
+ private:
   void ComputeRequirement() override {
-    requirement_.min_x = 0;
-    requirement_.min_y = 0;
-    requirement_.flex_grow_x = 0;
-    requirement_.flex_grow_y = 0;
-    requirement_.flex_shrink_x = 0;
-    requirement_.flex_shrink_y = 0;
-    requirement_.selection = Requirement::NORMAL;
+    requirement_ = Requirement{};
+
     for (auto& child : children_) {
       child->ComputeRequirement();
-      if (requirement_.selection < child->requirement().selection) {
-        requirement_.selection = child->requirement().selection;
-        requirement_.selected_box = child->requirement().selected_box;
-        requirement_.selected_box.x_min += requirement_.min_x;
-        requirement_.selected_box.x_max += requirement_.min_x;
+
+      // Propagate the focused requirement.
+      if (requirement_.focused.Prefer(child->requirement().focused)) {
+        requirement_.focused = child->requirement().focused;
+        requirement_.focused.box.Shift(requirement_.min_x, 0);
       }
+
+      // Extend the min_x and min_y to contain all the children
       requirement_.min_x += child->requirement().min_x;
       requirement_.min_y =
           std::max(requirement_.min_y, child->requirement().min_y);
@@ -64,6 +62,19 @@ class HBox : public Node {
       x = box.x_max + 1;
     }
   }
+
+  void Select(Selection& selection) override {
+    // If this Node box_ doesn't intersect with the selection, then no
+    // selection.
+    if (Box::Intersection(selection.GetBox(), box_).IsEmpty()) {
+      return;
+    }
+
+    Selection selection_saturated = selection.SaturateHorizontal(box_);
+    for (auto& child : children_) {
+      child->Select(selection_saturated);
+    }
+  }
 };
 
 }  // namespace

src/ftxui/dom/italic.cpp

@@ -0,0 +1,35 @@
+// Copyright 2025 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <memory>   // for make_shared
+#include <utility>  // for move
+
+#include "ftxui/dom/elements.hpp"        // for Element, underlinedDouble
+#include "ftxui/dom/node.hpp"            // for Node
+#include "ftxui/dom/node_decorator.hpp"  // for NodeDecorator
+#include "ftxui/screen/box.hpp"          // for Box
+#include "ftxui/screen/screen.hpp"       // for Pixel, Screen
+
+namespace ftxui {
+
+/// @brief Apply a underlinedDouble to text.
+/// @ingroup dom
+Element italic(Element child) {
+  class Impl : public NodeDecorator {
+   public:
+    using NodeDecorator::NodeDecorator;
+
+    void Render(Screen& screen) override {
+      for (int y = box_.y_min; y <= box_.y_max; ++y) {
+        for (int x = box_.x_min; x <= box_.x_max; ++x) {
+          screen.PixelAt(x, y).italic = true;
+        }
+      }
+      Node::Render(screen);
+    }
+  };
+
+  return std::make_shared<Impl>(std::move(child));
+}
+
+}  // namespace ftxui

src/ftxui/dom/italic_test.cpp

@@ -0,0 +1,22 @@
+// Copyright 2025 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <string>  // for allocator, string
+
+#include "ftxui/dom/elements.hpp"   // for operator|, text, bold, Element
+#include "ftxui/dom/node.hpp"       // for Render
+#include "ftxui/screen/screen.hpp"  // for Screen, Pixel
+#include "gtest/gtest.h"  // for Test, AssertionResult, EXPECT_TRUE, Message, TEST, TestPartResult
+
+// NOLINTBEGIN
+namespace ftxui {
+
+TEST(ItalicTest, Basic) {
+  auto element = text("text") | italic;
+  Screen screen(5, 1);
+  Render(screen, element);
+  EXPECT_TRUE(screen.PixelAt(0, 0).italic);
+}
+
+}  // namespace ftxui
+// NOLINTEND

src/ftxui/dom/linear_gradient.cpp

@@ -97,7 +97,11 @@ Color Interpolate(const LinearGradientNormalized& gradient, float t) {
   // Find the right color in the gradient's stops.
   size_t i = 1;
   while (true) {
-    if (i > gradient.positions.size()) {
+    // Note that `t` might be slightly greater than 1.0 due to floating point
+    // precision. This is why we need to handle the case where `t` is greater
+    // than the last stop's position.
+    // See https://github.com/ArthurSonzogni/FTXUI/issues/998
+    if (i >= gradient.positions.size()) {
       const float half = 0.5F;
       return Color::Interpolate(half, gradient.colors.back(),
                                 gradient.colors.back());

src/ftxui/dom/node.cpp

@@ -2,9 +2,12 @@
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.
 #include <ftxui/screen/box.hpp>  // for Box
-#include <utility>               // for move
+#include <string>
+#include <utility>  // for move
 
+#include <cstddef>
 #include "ftxui/dom/node.hpp"
+#include "ftxui/dom/selection.hpp"  // for Selection
 #include "ftxui/screen/screen.hpp"  // for Screen
 
 namespace ftxui {
@@ -16,9 +19,23 @@ Node::~Node() = default;
 /// @brief Compute how much space an elements needs.
 /// @ingroup dom
 void Node::ComputeRequirement() {
+  if (children_.empty()) {
+    return;
+  }
   for (auto& child : children_) {
     child->ComputeRequirement();
   }
+
+  // By default, the requirement is the one of the first child.
+  requirement_ = children_[0]->requirement();
+
+  // Propagate the focused requirement.
+  for (size_t i = 1; i < children_.size(); ++i) {
+    if (!requirement_.focused.enabled &&
+        children_[i]->requirement().focused.enabled) {
+      requirement_.focused = children_[i]->requirement().focused;
+    }
+  }
 }
 
 /// @brief Assign a position and a dimension to an element for drawing.
@@ -27,6 +44,20 @@ void Node::SetBox(Box box) {
   box_ = box;
 }
 
+/// @brief Compute the selection of an element.
+/// @ingroup dom
+void Node::Select(Selection& selection) {
+  // If this Node box_ doesn't intersect with the selection, then no selection.
+  if (Box::Intersection(selection.GetBox(), box_).IsEmpty()) {
+    return;
+  }
+
+  // By default we defer the selection to the children.
+  for (auto& child : children_) {
+    child->Select(selection);
+  }
+}
+
 /// @brief Display an element on a ftxui::Screen.
 /// @ingroup dom
 void Node::Render(Screen& screen) {
@@ -42,15 +73,31 @@ void Node::Check(Status* status) {
   status->need_iteration |= (status->iteration == 0);
 }
 
+std::string Node::GetSelectedContent(Selection& selection) {
+  std::string content;
+
+  for (auto& child : children_) {
+    content += child->GetSelectedContent(selection);
+  }
+
+  return content;
+}
+
 /// @brief Display an element on a ftxui::Screen.
 /// @ingroup dom
 void Render(Screen& screen, const Element& element) {
-  Render(screen, element.get());
+  Selection selection;
+  Render(screen, element.get(), selection);
 }
 
 /// @brief Display an element on a ftxui::Screen.
 /// @ingroup dom
 void Render(Screen& screen, Node* node) {
+  Selection selection;
+  Render(screen, node, selection);
+}
+
+void Render(Screen& screen, Node* node, Selection& selection) {
   Box box;
   box.x_min = 0;
   box.y_min = 0;
@@ -73,12 +120,85 @@ void Render(Screen& screen, Node* node) {
     node->Check(&status);
   }
 
-  // Step 3: Draw the element.
+  // Step 3: Selection
+  if (!selection.IsEmpty()) {
+    node->Select(selection);
+  }
+
+  if (node->requirement().focused.enabled
+#if defined(FTXUI_MICROSOFT_TERMINAL_FALLBACK)
+      // Setting the cursor to the right position allow folks using CJK (China,
+      // Japanese, Korean, ...) characters to see their [input method editor]
+      // displayed at the right location. See [issue].
+      //
+      // [input method editor]:
+      // https://en.wikipedia.org/wiki/Input_method
+      //
+      // [issue]:
+      // https://github.com/ArthurSonzogni/FTXUI/issues/2#issuecomment-505282355
+      //
+      // Unfortunately, Microsoft terminal do not handle properly hiding the
+      // cursor. Instead the character under the cursor is hidden, which is a
+      // big problem. As a result, we can't enable setting cursor to the right
+      // location. It will be displayed at the bottom right corner.
+      // See:
+      // https://github.com/microsoft/terminal/issues/1203
+      // https://github.com/microsoft/terminal/issues/3093
+      &&
+      node->requirement().focused.cursor_shape != Screen::Cursor::Shape::Hidden
+#endif
+  ) {
+    screen.SetCursor(Screen::Cursor{
+        node->requirement().focused.node->box_.x_max,
+        node->requirement().focused.node->box_.y_max,
+        node->requirement().focused.cursor_shape,
+    });
+  } else {
+    screen.SetCursor(Screen::Cursor{
+        screen.dimx() - 1,
+        screen.dimy() - 1,
+        Screen::Cursor::Shape::Hidden,
+    });
+  }
+
+  // Step 4: Draw the element.
   screen.stencil = box;
   node->Render(screen);
 
-  // Step 4: Apply shaders
+  // Step 5: Apply shaders
   screen.ApplyShader();
 }
 
+std::string GetNodeSelectedContent(Screen& screen,
+                                   Node* node,
+                                   Selection& selection) {
+  Box box;
+  box.x_min = 0;
+  box.y_min = 0;
+  box.x_max = screen.dimx() - 1;
+  box.y_max = screen.dimy() - 1;
+
+  Node::Status status;
+  node->Check(&status);
+  const int max_iterations = 20;
+  while (status.need_iteration && status.iteration < max_iterations) {
+    // Step 1: Find what dimension this elements wants to be.
+    node->ComputeRequirement();
+
+    // Step 2: Assign a dimension to the element.
+    node->SetBox(box);
+
+    // Check if the element needs another iteration of the layout algorithm.
+    status.need_iteration = false;
+    status.iteration++;
+    node->Check(&status);
+  }
+
+  // Step 3: Selection
+  node->Select(selection);
+
+  // Step 4: get the selected content.
+  return node->GetSelectedContent(selection);
+}
+
 }  // namespace ftxui

src/ftxui/dom/paragraph.cpp

@@ -1,9 +1,10 @@
 // Copyright 2020 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.
-#include <sstream>  // for basic_istream, stringstream
-#include <string>   // for string, allocator, getline
-#include <utility>  // for move
+#include <functional>  // for function
+#include <sstream>     // for basic_istream, stringstream
+#include <string>      // for string, allocator, getline
+#include <utility>     // for move
 
 #include "ftxui/dom/elements.hpp"  // for flexbox, Element, text, Elements, operator|, xflex, paragraph, paragraphAlignCenter, paragraphAlignJustify, paragraphAlignLeft, paragraphAlignRight
 #include "ftxui/dom/flexbox_config.hpp"  // for FlexboxConfig, FlexboxConfig::JustifyContent, FlexboxConfig::JustifyContent::Center, FlexboxConfig::JustifyContent::FlexEnd, FlexboxConfig::JustifyContent::SpaceBetween
@@ -20,6 +21,18 @@ Elements Split(const std::string& the_text) {
   }
   return output;
 }
+
+Element Split(const std::string& paragraph,
+              const std::function<Element(std::string)>& f) {
+  Elements output;
+  std::stringstream ss(paragraph);
+  std::string line;
+  while (std::getline(ss, line, '\n')) {
+    output.push_back(f(line));
+  }
+  return vbox(std::move(output));
+}
+
 }  // namespace
 
 /// @brief Return an element drawing the paragraph on multiple lines.
@@ -34,18 +47,22 @@ Element paragraph(const std::string& the_text) {
 /// @ingroup dom
 /// @see flexbox.
 Element paragraphAlignLeft(const std::string& the_text) {
-  static const auto config = FlexboxConfig().SetGap(1, 0);
-  return flexbox(Split(the_text), config);
-}
+  return Split(the_text, [](const std::string& line) {
+    static const auto config = FlexboxConfig().SetGap(1, 0);
+    return flexbox(Split(line), config);
+  });
+};
 
 /// @brief Return an element drawing the paragraph on multiple lines, aligned on
 /// the right.
 /// @ingroup dom
 /// @see flexbox.
 Element paragraphAlignRight(const std::string& the_text) {
-  static const auto config =
-      FlexboxConfig().SetGap(1, 0).Set(FlexboxConfig::JustifyContent::FlexEnd);
-  return flexbox(Split(the_text), config);
+  return Split(the_text, [](const std::string& line) {
+    static const auto config = FlexboxConfig().SetGap(1, 0).Set(
+        FlexboxConfig::JustifyContent::FlexEnd);
+    return flexbox(Split(line), config);
+  });
 }
 
 /// @brief Return an element drawing the paragraph on multiple lines, aligned on
@@ -53,9 +70,11 @@ Element paragraphAlignRight(const std::string& the_text) {
 /// @ingroup dom
 /// @see flexbox.
 Element paragraphAlignCenter(const std::string& the_text) {
-  static const auto config =
-      FlexboxConfig().SetGap(1, 0).Set(FlexboxConfig::JustifyContent::Center);
-  return flexbox(Split(the_text), config);
+  return Split(the_text, [](const std::string& line) {
+    static const auto config =
+        FlexboxConfig().SetGap(1, 0).Set(FlexboxConfig::JustifyContent::Center);
+    return flexbox(Split(line), config);
+  });
 }
 
 /// @brief Return an element drawing the paragraph on multiple lines, aligned
@@ -64,11 +83,13 @@ Element paragraphAlignCenter(const std::string& the_text) {
 /// @ingroup dom
 /// @see flexbox.
 Element paragraphAlignJustify(const std::string& the_text) {
-  static const auto config = FlexboxConfig().SetGap(1, 0).Set(
-      FlexboxConfig::JustifyContent::SpaceBetween);
-  Elements words = Split(the_text);
-  words.push_back(text("") | xflex);
-  return flexbox(std::move(words), config);
+  return Split(the_text, [](const std::string& line) {
+    static const auto config = FlexboxConfig().SetGap(1, 0).Set(
+        FlexboxConfig::JustifyContent::SpaceBetween);
+    Elements words = Split(line);
+    words.push_back(text("") | xflex);
+    return flexbox(std::move(words), config);
+  });
 }
 
 }  // namespace ftxui

src/ftxui/dom/scroll_indicator_test.cpp

@@ -5,7 +5,7 @@
 #include <string>   // for allocator, to_string, string
 #include <utility>  // for move
 
-#include "ftxui/dom/elements.hpp"  // for operator|, Element, operator|=, text, vbox, Elements, border, focus, frame, vscroll_indicator
+#include "ftxui/dom/elements.hpp"  // for operator|, Element, operator|=, text, vbox, Elements, border, select, frame, vscroll_indicator
 #include "ftxui/dom/node.hpp"      // for Render
 #include "ftxui/screen/color.hpp"  // for Color, Color::Red
 #include "ftxui/screen/screen.hpp"  // for Screen

src/ftxui/dom/selection.cpp

@@ -0,0 +1,173 @@
+// Copyright 2024 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+
+#include "ftxui/dom/selection.hpp"  // for Selection
+#include <algorithm>                // for max, min
+#include <string>                   // for string
+#include <tuple>                    // for ignore
+
+#include "ftxui/dom/node_decorator.hpp"  // for NodeDecorator
+
+namespace ftxui {
+
+namespace {
+class Unselectable : public NodeDecorator {
+ public:
+  using NodeDecorator::NodeDecorator;
+
+  void Select(Selection& ignored) override {
+    std::ignore = ignored;
+    // Overwrite the select method to do nothing.
+  }
+};
+}  // namespace
+
+/// @brief Create an empty selection.
+Selection::Selection() = default;
+
+/// @brief Create a selection.
+/// @param start_x The x coordinate of the start of the selection.
+/// @param start_y The y coordinate of the start of the selection.
+/// @param end_x The x coordinate of the end of the selection.
+/// @param end_y The y coordinate of the end of the selection.
+Selection::Selection(int start_x, int start_y, int end_x, int end_y)
+    : start_x_(start_x),
+      start_y_(start_y),
+      end_x_(end_x),
+      end_y_(end_y),
+      box_{
+          std::min(start_x, end_x),
+          std::max(start_x, end_x),
+          std::min(start_y, end_y),
+          std::max(start_y, end_y),
+      },
+      empty_(false) {}
+
+Selection::Selection(int start_x,
+                     int start_y,
+                     int end_x,
+                     int end_y,
+                     Selection* parent)
+    : start_x_(start_x),
+      start_y_(start_y),
+      end_x_(end_x),
+      end_y_(end_y),
+      box_{
+          std::min(start_x, end_x),
+          std::max(start_x, end_x),
+          std::min(start_y, end_y),
+          std::max(start_y, end_y),
+      },
+      parent_(parent),
+      empty_(false) {}
+
+/// @brief Get the box of the selection.
+/// @return The box of the selection.
+const Box& Selection::GetBox() const {
+  return box_;
+}
+
+/// @brief Saturate the selection to be inside the box.
+/// This is called by `hbox` to propagate the selection to its children.
+/// @param box The box to saturate the selection in.
+/// @return The saturated selection.
+Selection Selection::SaturateHorizontal(Box box) {
+  int start_x = start_x_;
+  int start_y = start_y_;
+  int end_x = end_x_;
+  int end_y = end_y_;
+
+  const bool start_outside = !box.Contain(start_x, start_y);
+  const bool end_outside = !box.Contain(end_x, end_y);
+  const bool properly_ordered =
+      start_y < end_y || (start_y == end_y && start_x <= end_x);
+  if (properly_ordered) {
+    if (start_outside) {
+      start_x = box.x_min;
+      start_y = box.y_min;
+    }
+    if (end_outside) {
+      end_x = box.x_max;
+      end_y = box.y_max;
+    }
+  } else {
+    if (start_outside) {
+      start_x = box.x_max;
+      start_y = box.y_max;
+    }
+    if (end_outside) {
+      end_x = box.x_min;
+      end_y = box.y_min;
+    }
+  }
+  return {
+      start_x, start_y, end_x, end_y, parent_,
+  };
+}
+
+/// @brief Saturate the selection to be inside the box.
+/// This is called by `vbox` to propagate the selection to its children.
+/// @param box The box to saturate the selection in.
+/// @return The saturated selection.
+Selection Selection::SaturateVertical(Box box) {
+  int start_x = start_x_;
+  int start_y = start_y_;
+  int end_x = end_x_;
+  int end_y = end_y_;
+
+  const bool start_outside = !box.Contain(start_x, start_y);
+  const bool end_outside = !box.Contain(end_x, end_y);
+  const bool properly_ordered =
+      start_y < end_y || (start_y == end_y && start_x <= end_x);
+
+  if (properly_ordered) {
+    if (start_outside) {
+      start_x = box.x_min;
+      start_y = box.y_min;
+    }
+    if (end_outside) {
+      end_x = box.x_max;
+      end_y = box.y_max;
+    }
+  } else {
+    if (start_outside) {
+      start_x = box.x_max;
+      start_y = box.y_max;
+    }
+    if (end_outside) {
+      end_x = box.x_min;
+      end_y = box.y_min;
+    }
+  }
+  return {start_x, start_y, end_x, end_y, parent_};
+}
+
+void Selection::AddPart(const std::string& part, int y, int left, int right) {
+  if (parent_ != this) {
+    parent_->AddPart(part, y, left, right);
+    return;
+  }
+  [&] {
+    if (parts_.str().empty()) {
+      parts_ << part;
+      return;
+    }
+
+    if (y_ != y) {
+      parts_ << '\n' << part;
+      return;
+    }
+
+    if (x_ == left + 1) {
+      parts_ << part;
+      return;
+    }
+
+    parts_ << part;
+  }();
+  y_ = y;
+  x_ = right;
+}
+
+}  // namespace ftxui

src/ftxui/dom/selection_style.cpp

@@ -0,0 +1,92 @@
+// Copyright 2024 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <functional>  // for function
+#include <memory>      // for make_shared
+#include <utility>     // for move
+
+#include "ftxui/dom/elements.hpp"  // for Element, Decorator, bgcolor, color
+#include "ftxui/dom/node_decorator.hpp"  // for NodeDecorator
+#include "ftxui/screen/color.hpp"        // for Color
+#include "ftxui/screen/pixel.hpp"        // for Pixel
+#include "ftxui/screen/screen.hpp"       // for Screen
+
+namespace ftxui {
+
+namespace {
+
+class SelectionStyleReset : public NodeDecorator {
+ public:
+  explicit SelectionStyleReset(Element child)
+      : NodeDecorator(std::move(child)) {}
+
+  void Render(Screen& screen) final {
+    auto old_style = screen.GetSelectionStyle();
+    screen.SetSelectionStyle([](Pixel&) {});
+    NodeDecorator::Render(screen);
+    screen.SetSelectionStyle(old_style);
+  }
+};
+
+class SelectionStyle : public NodeDecorator {
+ public:
+  SelectionStyle(Element child, const std::function<void(Pixel&)>& style)
+      : NodeDecorator(std::move(child)), style_(style) {}
+
+  void Render(Screen& screen) final {
+    auto old_style = screen.GetSelectionStyle();
+    auto new_style = [&, old_style](Pixel& pixel) {
+      old_style(pixel);
+      style_(pixel);
+    };
+    screen.SetSelectionStyle(new_style);
+    NodeDecorator::Render(screen);
+    screen.SetSelectionStyle(old_style);
+  }
+
+  std::function<void(Pixel&)> style_;
+};
+
+}  // namespace
+
+/// @brief Reset the selection style of an element.
+/// @param child The input element.
+/// @return The output element with the selection style reset.
+Element selectionStyleReset(Element child) {
+  return std::make_shared<SelectionStyleReset>(std::move(child));
+}
+
+/// @brief Set the background color of an element when selected.
+/// Note that the style is applied on top of the existing style.
+Decorator selectionBackgroundColor(Color foreground) {
+  return selectionStyle([foreground](Pixel& pixel) {  //
+    pixel.background_color = foreground;
+  });
+}
+
+/// @brief Set the foreground color of an element when selected.
+/// Note that the style is applied on top of the existing style.
+Decorator selectionForegroundColor(Color foreground) {
+  return selectionStyle([foreground](Pixel& pixel) {  //
+    pixel.foreground_color = foreground;
+  });
+}
+
+/// @brief Set the color of an element when selected.
+/// @param foreground The color to be applied.
+/// Note that the style is applied on top of the existing style.
+Decorator selectionColor(Color foreground) {
+  return selectionForegroundColor(foreground);
+}
+
+/// @brief Set the style of an element when selected.
+/// @param style The style to be applied.
+/// Note that the style is applied on top of the existing style.
+// NOLINTNEXTLINE
+Decorator selectionStyle(std::function<void(Pixel&)> style) {
+  return [style](Element child) -> Element {
+    return std::make_shared<SelectionStyle>(std::move(child), style);
+  };
+}
+
+}  // namespace ftxui

src/ftxui/dom/selection_test.cpp

@@ -0,0 +1,224 @@
+// Copyright 2022 Arthur Sonzogni. All rights reserved.
+// Use of this source code is governed by the MIT license that can be found in
+// the LICENSE file.
+#include <gtest/gtest.h>
+#include <csignal>  // for raise, SIGABRT, SIGFPE, SIGILL, SIGINT, SIGSEGV, SIGTERM
+
+#include "ftxui/component/component.hpp"  // for Input, Renderer, Vertical
+#include "ftxui/component/event.hpp"      // for Event
+#include "ftxui/component/loop.hpp"       // for Loop
+#include "ftxui/component/mouse.hpp"  // for Mouse, Mouse::Left, Mouse::Pressed, Mouse::Released
+#include "ftxui/component/screen_interactive.hpp"
+#include "ftxui/dom/elements.hpp"   // for text
+#include "ftxui/dom/node.hpp"       // for Render
+#include "ftxui/screen/screen.hpp"  // for Screen
+
+// NOLINTBEGIN
+namespace ftxui {
+
+namespace {
+Event MousePressed(int x, int y) {
+  Mouse mouse;
+  mouse.button = Mouse::Left;
+  mouse.motion = Mouse::Pressed;
+  mouse.shift = false;
+  mouse.meta = false;
+  mouse.control = false;
+  mouse.x = x;
+  mouse.y = y;
+  return Event::Mouse("", mouse);
+}
+
+Event MouseReleased(int x, int y) {
+  Mouse mouse;
+  mouse.button = Mouse::Left;
+  mouse.motion = Mouse::Released;
+  mouse.shift = false;
+  mouse.meta = false;
+  mouse.control = false;
+  mouse.x = x;
+  mouse.y = y;
+  return Event::Mouse("", mouse);
+}
+
+Event MouseMove(int x, int y) {
+  Mouse mouse;
+  mouse.button = Mouse::Left;
+  mouse.motion = Mouse::Moved;
+  mouse.shift = false;
+  mouse.meta = false;
+  mouse.control = false;
+  mouse.x = x;
+  mouse.y = y;
+  return Event::Mouse("", mouse);
+}
+
+}  // namespace
+
+TEST(SelectionTest, DefaultSelection) {
+  auto component = Renderer([&] { return text("Lorem ipsum dolor"); });
+  auto screen = ScreenInteractive::FixedSize(20, 1);
+  EXPECT_EQ(screen.GetSelection(), "");
+  Loop loop(&screen, component);
+  screen.PostEvent(MousePressed(3, 1));
+  screen.PostEvent(MouseReleased(10, 1));
+  loop.RunOnce();
+
+  EXPECT_EQ(screen.GetSelection(), "rem ipsu");
+}
+
+TEST(SelectionTest, SelectionChange) {
+  int selectionChangeCounter = 0;
+  auto component = Renderer([&] { return text("Lorem ipsum dolor"); });
+  auto screen = ScreenInteractive::FixedSize(20, 1);
+  screen.SelectionChange([&] { selectionChangeCounter++; });
+
+  Loop loop(&screen, component);
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 0);
+
+  screen.PostEvent(MousePressed(3, 1));
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 0);
+
+  screen.PostEvent(MouseMove(5, 1));
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 1);
+
+  screen.PostEvent(MouseMove(7, 1));
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 2);
+
+  screen.PostEvent(MouseReleased(10, 1));
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 3);
+
+  screen.PostEvent(MouseMove(10, 1));
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 3);
+
+  EXPECT_EQ(screen.GetSelection(), "rem ipsu");
+}
+
+// Check that submitting multiple mouse events quickly doesn't trigger multiple
+// selection change events.
+TEST(SelectionTest, SelectionOnChangeSquashedEvents) {
+  int selectionChangeCounter = 0;
+  auto component = Renderer([&] { return text("Lorem ipsum dolor"); });
+  auto screen = ScreenInteractive::FixedSize(20, 1);
+  screen.SelectionChange([&] { selectionChangeCounter++; });
+
+  Loop loop(&screen, component);
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 0);
+
+  screen.PostEvent(MousePressed(3, 1));
+  screen.PostEvent(MouseMove(5, 1));
+  screen.PostEvent(MouseMove(7, 1));
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 1);
+
+  screen.PostEvent(MouseReleased(10, 1));
+  screen.PostEvent(MouseMove(10, 1));
+  loop.RunOnce();
+  EXPECT_EQ(selectionChangeCounter, 2);
+
+  EXPECT_EQ(screen.GetSelection(), "rem ipsu");
+}
+
+TEST(SelectionTest, StyleSelection) {
+  int selectionChangeCounter = 0;
+
+  auto element = hbox({
+      text("Lorem "),
+      text("ipsum") | selectionColor(Color::Red),
+      text(" dolor"),
+  });
+
+  auto screen = ScreenInteractive::FixedSize(20, 1);
+  Selection selection(2, 0, 9, 0);
+
+  Render(screen, element.get(), selection);
+  for (int i = 0; i < 20; i++) {
+    if (i >= 2 && i <= 9) {
+      EXPECT_EQ(screen.PixelAt(i, 0).inverted, true);
+    } else {
+      EXPECT_EQ(screen.PixelAt(i, 0).inverted, false);
+    }
+
+    if (i >= 6 && i <= 9) {
+      EXPECT_EQ(screen.PixelAt(i, 0).foreground_color, Color::Red);
+    } else {
+      EXPECT_EQ(screen.PixelAt(i, 0).foreground_color, Color::Default);
+    }
+  }
+}
+
+TEST(SelectionTest, VBoxSelection) {
+  auto element = vbox({
+      text("Lorem ipsum dolor"),
+      text("Ut enim ad minim"),
+  });
+
+  auto screen = ScreenInteractive::FixedSize(20, 2);
+
+  Selection selection(2, 0, 2, 1);
+  Render(screen, element.get(), selection);
+
+  EXPECT_EQ(selection.GetParts(), "rem ipsum dolor\nUt ");
+  EXPECT_EQ(screen.ToString(),
+            "Lo\x1B[7mrem ipsum dolor\x1B[27m   \r\n"
+            "\x1B[7mUt \x1B[27menim ad minim    ");
+}
+
+TEST(SelectionTest, VBoxSaturatedSelection) {
+  auto element = vbox({
+      text("Lorem ipsum dolor"),
+      text("Ut enim ad minim"),
+      text("Duis aute irure"),
+  });
+
+  auto screen = ScreenInteractive::FixedSize(20, 3);
+  Selection selection(2, 0, 2, 2);
+  Render(screen, element.get(), selection);
+  EXPECT_EQ(selection.GetParts(), "rem ipsum dolor\nUt enim ad minim\nDui");
+
+  EXPECT_EQ(screen.ToString(),
+            "Lo\x1B[7mrem ipsum dolor\x1B[27m   \r\n"
+            "\x1B[7mUt enim ad minim\x1B[27m    \r\n"
+            "\x1B[7mDui\x1B[27ms aute irure     ");
+}
+
+TEST(SelectionTest, HBoxSelection) {
+  auto element = hbox({
+      text("Lorem ipsum dolor"),
+      text("Ut enim ad minim"),
+  });
+
+  auto screen = ScreenInteractive::FixedSize(40, 1);
+  Selection selection(2, 0, 20, 0);
+  Render(screen, element.get(), selection);
+  EXPECT_EQ(selection.GetParts(), "rem ipsum dolorUt e");
+  EXPECT_EQ(screen.ToString(),
+            "Lo\x1B[7mrem ipsum dolorUt e\x1B[27mnim ad minim       ");
+}
+
+TEST(SelectionTest, HBoxSaturatedSelection) {
+  auto element = hbox({
+      text("Lorem ipsum dolor"),
+      text("Ut enim ad minim"),
+      text("Duis aute irure"),
+  });
+
+  auto screen = ScreenInteractive::FixedSize(60, 1);
+
+  Selection selection(2, 0, 35, 0);
+  Render(screen, element.get(), selection);
+  EXPECT_EQ(selection.GetParts(), "rem ipsum dolorUt enim ad minimDui");
+  EXPECT_EQ(screen.ToString(),
+            "Lo\x1B[7mrem ipsum dolorUt enim ad minimDui\x1B[27ms aute irure   "
+            "         ");
+}
+
+}  // namespace ftxui
+// NOLINTEND

src/ftxui/dom/table.cpp

@@ -3,7 +3,8 @@
 // the LICENSE file.
 #include "ftxui/dom/table.hpp"
 
-#include <algorithm>  // for max
+#include <algorithm>         // for max
+#include <initializer_list>  // for initializer_list
 #include <memory>   // for allocator, shared_ptr, allocator_traits<>::value_type
 #include <utility>  // for move, swap
 #include <vector>   // for vector

src/ftxui/dom/text.cpp

@@ -3,13 +3,15 @@
 // the LICENSE file.
 #include <algorithm>  // for min
 #include <memory>     // for make_shared
-#include <string>     // for string, wstring
-#include <utility>    // for move
+#include <sstream>
+#include <string>   // for string, wstring
+#include <utility>  // for move
 
 #include "ftxui/dom/deprecated.hpp"   // for text, vtext
 #include "ftxui/dom/elements.hpp"     // for Element, text, vtext
 #include "ftxui/dom/node.hpp"         // for Node
 #include "ftxui/dom/requirement.hpp"  // for Requirement
+#include "ftxui/dom/selection.hpp"    // for Selection
 #include "ftxui/screen/box.hpp"       // for Box
 #include "ftxui/screen/screen.hpp"    // for Pixel, Screen
 #include "ftxui/screen/string.hpp"  // for string_width, Utf8ToGlyphs, to_string
@@ -26,28 +28,67 @@ class Text : public Node {
   void ComputeRequirement() override {
     requirement_.min_x = string_width(text_);
     requirement_.min_y = 1;
+    has_selection = false;
+  }
+
+  void Select(Selection& selection) override {
+    if (Box::Intersection(selection.GetBox(), box_).IsEmpty()) {
+      return;
+    }
+
+    const Selection selection_saturated = selection.SaturateHorizontal(box_);
+
+    has_selection = true;
+    selection_start_ = selection_saturated.GetBox().x_min;
+    selection_end_ = selection_saturated.GetBox().x_max;
+
+    std::stringstream ss;
+    int x = box_.x_min;
+    for (const auto& cell : Utf8ToGlyphs(text_)) {
+      if (cell == "\n") {
+        continue;
+      }
+      if (selection_start_ <= x && x <= selection_end_) {
+        ss << cell;
+      }
+      x++;
+    }
+    selection.AddPart(ss.str(), box_.y_min, selection_start_, selection_end_);
   }
 
   void Render(Screen& screen) override {
     int x = box_.x_min;
     const int y = box_.y_min;
+
     if (y > box_.y_max) {
       return;
     }
+
     for (const auto& cell : Utf8ToGlyphs(text_)) {
       if (x > box_.x_max) {
-        return;
+        break;
       }
       if (cell == "\n") {
         continue;
       }
       screen.PixelAt(x, y).character = cell;
+
+      if (has_selection) {
+        auto selectionTransform = screen.GetSelectionStyle();
+        if ((x >= selection_start_) && (x <= selection_end_)) {
+          selectionTransform(screen.PixelAt(x, y));
+        }
+      }
+
       ++x;
     }
   }
 
  private:
   std::string text_;
+  bool has_selection = false;
+  int selection_start_ = 0;
+  int selection_end_ = -1;
 };
 
 class VText : public Node {

src/ftxui/dom/vbox.cpp

@@ -11,6 +11,7 @@
 #include "ftxui/dom/elements.hpp"     // for Element, Elements, vbox
 #include "ftxui/dom/node.hpp"         // for Node, Elements
 #include "ftxui/dom/requirement.hpp"  // for Requirement
+#include "ftxui/dom/selection.hpp"    // for Selection
 #include "ftxui/screen/box.hpp"       // for Box
 
 namespace ftxui {
@@ -20,22 +21,20 @@ class VBox : public Node {
  public:
   explicit VBox(Elements children) : Node(std::move(children)) {}
 
+ private:
   void ComputeRequirement() override {
-    requirement_.min_x = 0;
-    requirement_.min_y = 0;
-    requirement_.flex_grow_x = 0;
-    requirement_.flex_grow_y = 0;
-    requirement_.flex_shrink_x = 0;
-    requirement_.flex_shrink_y = 0;
-    requirement_.selection = Requirement::NORMAL;
+    requirement_ = Requirement{};
+
     for (auto& child : children_) {
       child->ComputeRequirement();
-      if (requirement_.selection < child->requirement().selection) {
-        requirement_.selection = child->requirement().selection;
-        requirement_.selected_box = child->requirement().selected_box;
-        requirement_.selected_box.y_min += requirement_.min_y;
-        requirement_.selected_box.y_max += requirement_.min_y;
+
+      // Propagate the focused requirement.
+      if (requirement_.focused.Prefer(child->requirement().focused)) {
+        requirement_.focused = child->requirement().focused;
+        requirement_.focused.box.Shift(0, requirement_.min_y);
       }
+
+      // Extend the min_x and min_y to contain all the children
       requirement_.min_y += child->requirement().min_y;
       requirement_.min_x =
           std::max(requirement_.min_x, child->requirement().min_x);
@@ -64,6 +63,20 @@ class VBox : public Node {
       y = box.y_max + 1;
     }
   }
+
+  void Select(Selection& selection) override {
+    // If this Node box_ doesn't intersect with the selection, then no
+    // selection.
+    if (Box::Intersection(selection.GetBox(), box_).IsEmpty()) {
+      return;
+    }
+
+    Selection selection_saturated = selection.SaturateVertical(box_);
+
+    for (auto& child : children_) {
+      child->Select(selection_saturated);
+    }
+  }
 };
 }  // namespace
 

src/ftxui/screen/box.cpp

@@ -30,6 +30,17 @@ Box Box::Union(Box a, Box b) {
   };
 }
 
+/// Shift the box by (x,y).
+/// @param x horizontal shift.
+/// @param y vertical shift.
+/// @ingroup screen
+void Box::Shift(int x, int y) {
+  x_min += x;
+  x_max += x;
+  y_min += y;
+  y_max += y;
+}
+
 /// @return whether (x,y) is contained inside the box.
 /// @ingroup screen
 bool Box::Contain(int x, int y) const {

src/ftxui/screen/screen.cpp

@@ -106,6 +106,12 @@ void UpdatePixelStyle(const Screen* screen,
                          : "\x1B[27m");  // INVERTED_RESET
   }
 
+  // Italics
+  if (FTXUI_UNLIKELY(next.italic != prev.italic)) {
+    ss << (next.italic ? "\x1B[3m"     // ITALIC_SET
+                       : "\x1B[23m");  // ITALIC_RESET
+  }
+
   // StrikeThrough
   if (FTXUI_UNLIKELY(next.strikethrough != prev.strikethrough)) {
     ss << (next.strikethrough ? "\x1B[9m"     // CROSSED_OUT
@@ -544,4 +550,16 @@ const std::string& Screen::Hyperlink(std::uint8_t id) const {
   return hyperlinks_[id];
 }
 
+/// @brief Return the current selection style.
+/// @see SetSelectionStyle
+const Screen::SelectionStyle& Screen::GetSelectionStyle() const {
+  return selection_style_;
+}
+
+/// @brief Set the current selection style.
+/// @see GetSelectionStyle
+void Screen::SetSelectionStyle(SelectionStyle decorator) {
+  selection_style_ = std::move(decorator);
+}
+
 }  // namespace ftxui

tools/license_headers.cpp

@@ -1,4 +1,4 @@
-// Copyright 2023 Arthur Sonzogni. All rights reserved.
+// Copyright 2024 Arthur Sonzogni. All rights reserved.
 // Use of this source code is governed by the MIT license that can be found in
 // the LICENSE file.