Use IWYU.

include/ftxui/component/button.hpp

@@ -2,10 +2,14 @@
 #define FTXUI_COMPONENT_BUTTON_HPP
 
 #include <functional>
+#include <string>
 
 #include "ftxui/component/component.hpp"
+#include "ftxui/dom/elements.hpp"
+#include "ftxui/screen/box.hpp"
 
 namespace ftxui {
+struct Event;
 
 /// @brief A button. An action is associated to the click event.
 /// @ingroup dom
@@ -25,6 +29,7 @@ class Button : public Component {
   // Component implementation.
   Element Render() override;
   bool OnEvent(Event) override;
+
  private:
   Box box_;
 };

include/ftxui/component/captured_mouse.hpp

@@ -12,3 +12,7 @@ using CapturedMouse = std::unique_ptr<CapturedMouseInterface>;
 }  // namespace ftxui
 
 #endif /* end of include guard: FTXUI_CAPTURED_MOUSE_HPP */
+
+// 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/ftxui/component/checkbox.hpp

@@ -1,11 +1,13 @@
 #ifndef FTXUI_COMPONENT_CHECKBOX_HPP
 #define FTXUI_COMPONENT_CHECKBOX_HPP
 
-#include <functional>
+#include <string>
 
 #include "ftxui/component/component.hpp"
+#include "ftxui/screen/box.hpp"
 
 namespace ftxui {
+struct Event;
 
 /// @brief A Checkbox. It can be checked or unchecked.Display an element on a
 /// ftxui::Screen.
@@ -42,7 +44,6 @@ class CheckBox : public Component {
 
   int cursor_position = 0;
   Box box_;
-
 };
 
 }  // namespace ftxui

include/ftxui/component/component.hpp

@@ -1,14 +1,17 @@
 #ifndef FTXUI_COMPONENT_COMPONENT_HPP
 #define FTXUI_COMPONENT_COMPONENT_HPP
 
-#include <memory>
-#include "ftxui/component/event.hpp"
-#include "ftxui/dom/elements.hpp"
+#include <memory>  // for unique_ptr
+#include <vector>  // for vector
+
+#include "ftxui/component/captured_mouse.hpp"  // for CaptureMouse
+#include "ftxui/dom/elements.hpp"             // for Element
 
 namespace ftxui {
 
 class Delegate;
 class Focus;
+struct Event;
 
 /// @brief It implement rendering itself as ftxui::Element. It implement
 /// keyboard navigation by responding to ftxui::Event.
@@ -53,6 +56,8 @@ class Component {
   void TakeFocus();
 
  protected:
+  CapturedMouse CaptureMouse(const Event& event);
+
   std::vector<Component*> children_;
 
  private:

include/ftxui/component/container.hpp

@@ -2,6 +2,8 @@
 #define FTXUI_COMPONENT_CONTAINER_HPP
 
 #include "ftxui/component/component.hpp"
+#include "ftxui/component/event.hpp"
+#include "ftxui/dom/elements.hpp"
 
 namespace ftxui {
 

include/ftxui/component/event.hpp

@@ -1,16 +1,14 @@
 #ifndef FTXUI_COMPONENT_EVENT_HPP
 #define FTXUI_COMPONENT_EVENT_HPP
 
-#include <array>
-#include <ftxui/component/mouse.hpp>
-#include <ftxui/component/receiver.hpp>
-#include <functional>
-#include <string>
+#include <ftxui/component/mouse.hpp>  // for Mouse
+#include <string>                     // for string, operator==
 #include <vector>
 
 namespace ftxui {
 
 class ScreenInteractive;
+class Component;
 
 /// @brief Represent an event. It can be key press event, a terminal resize, or
 /// more ...
@@ -53,7 +51,7 @@ struct Event {
   static Event Custom;
 
   //--- Method section ---------------------------------------------------------
-  bool is_character() const { return type_ == Type::Character;}
+  bool is_character() const { return type_ == Type::Character; }
   wchar_t character() const { return character_; }
 
   bool is_mouse() const { return type_ == Type::Mouse; }
@@ -67,13 +65,12 @@ struct Event {
 
   const std::string& input() const { return input_; }
 
-  ScreenInteractive* screen() { return screen_; }
-  void SetScreen(ScreenInteractive* screen) { screen_ = screen; }
-
   bool operator==(const Event& other) const { return input_ == other.input_; }
 
   //--- State section ----------------------------------------------------------
  private:
+  friend Component;
+  friend ScreenInteractive;
   enum class Type {
     Unknown,
     Character,
@@ -94,10 +91,9 @@ struct Event {
   };
   std::string input_;
 
-  ScreenInteractive* screen_;
+  ScreenInteractive* screen_ = nullptr;
 };
 
-
 }  // namespace ftxui
 
 #endif /* end of include guard: FTXUI_COMPONENT_EVENT_HPP */

include/ftxui/component/input.hpp

@@ -2,10 +2,14 @@
 #define FTXUI_COMPONENT_INPUT_H_
 
 #include <functional>
+#include <string>
 
 #include "ftxui/component/component.hpp"
+#include "ftxui/dom/elements.hpp"
+#include "ftxui/screen/box.hpp"
 
 namespace ftxui {
+struct Event;
 
 /// @brief An input box. The user can type text into it.
 /// @ingroup component.

include/ftxui/component/menu.hpp

@@ -2,11 +2,15 @@
 #define FTXUI_COMPONENT_MENU
 
 #include <functional>
+#include <string>
+#include <vector>
 
 #include "ftxui/component/component.hpp"
 #include "ftxui/dom/elements.hpp"
+#include "ftxui/screen/box.hpp"
 
 namespace ftxui {
+struct Event;
 
 /// @brief A list of items. The user can navigate through them.
 /// @ingroup component

include/ftxui/component/mouse.hpp

@@ -1,3 +1,5 @@
+#ifndef FTXUI_COMPONENT_MOUSE_HPP
+#define FTXUI_COMPONENT_MOUSE_HPP
 namespace ftxui {
 
 /// @brief A mouse event. It contains the coordinate of the mouse, the button
@@ -39,3 +41,4 @@ struct Mouse {
 // 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.
+#endif /* end of include guard: FTXUI_COMPONENT_MOUSE_HPP */

include/ftxui/component/radiobox.hpp

@@ -1,11 +1,15 @@
 #ifndef FTXUI_COMPONENT_RADIOBOX_HPP
 #define FTXUI_COMPONENT_RADIOBOX_HPP
 
-#include <functional>
+#include <string>
+#include <vector>
 
 #include "ftxui/component/component.hpp"
+#include "ftxui/dom/elements.hpp"
+#include "ftxui/screen/box.hpp"
 
 namespace ftxui {
+struct Event;
 
 /// @brief A list of selectable element. One and only one can be selected at
 /// the same time.

include/ftxui/component/receiver.hpp

@@ -1,13 +1,13 @@
 #ifndef FTXUI_COMPONENT_RECEIVER_HPP_
 #define FTXUI_COMPONENT_RECEIVER_HPP_
 
-#include <atomic>
-#include <condition_variable>
+#include <atomic>              // for atomic
+#include <condition_variable>  // for condition_variable
 #include <functional>
 #include <iostream>
-#include <memory>
-#include <mutex>
-#include <queue>
+#include <memory>  // for unique_ptr, make_unique
+#include <mutex>   // for mutex, unique_lock
+#include <queue>   // for queue
 
 namespace ftxui {
 
@@ -38,6 +38,7 @@ namespace ftxui {
 // clang-format off
 template<class T> class SenderImpl;
 template<class T> class ReceiverImpl;
+
 template<class T> using Sender = std::unique_ptr<SenderImpl<T>>;
 template<class T> using Receiver = std::unique_ptr<ReceiverImpl<T>>;
 template<class T> Receiver<T> MakeReceiver();

include/ftxui/component/screen_interactive.hpp

@@ -1,20 +1,18 @@
 #ifndef FTXUI_COMPONENT_SCREEN_INTERACTIVE_HPP
 #define FTXUI_COMPONENT_SCREEN_INTERACTIVE_HPP
 
-#include <atomic>
-#include <condition_variable>
+#include <atomic>  // for atomic
 #include <ftxui/component/receiver.hpp>
-#include <functional>
-#include <memory>
-#include <mutex>
-#include <queue>
+#include <memory>  // for unique_ptr
+#include <string>  // for string
 
-#include "ftxui/component/captured_mouse.hpp"
+#include "ftxui/component/captured_mouse.hpp"  // for CapturedMouse
 #include "ftxui/component/event.hpp"
-#include "ftxui/screen/screen.hpp"
+#include "ftxui/screen/screen.hpp"  // for Screen
 
 namespace ftxui {
 class Component;
+struct Event;
 
 class ScreenInteractive : public Screen {
  public:

include/ftxui/component/slider.hpp

@@ -11,13 +11,8 @@ namespace ftxui {
 // float max = 100.f,
 // float increment = (max - min) * 0.05f);
 
-template<class T> // T = {int, float}
-ComponentPtr Slider(std::wstring label,
-                    T* value,
-                    T min,
-                    T max,
-                    T increment);
-
+template <class T>  // T = {int, float}
+ComponentPtr Slider(std::wstring label, T* value, T min, T max, T increment);
 
 }  // namespace ftxui
 

include/ftxui/component/toggle.hpp

@@ -1,12 +1,15 @@
 #ifndef FTXUI_COMPONENT_TOGGLE_H_
 #define FTXUI_COMPONENT_TOGGLE_H_
 
-#include <functional>
 #include <string>
+#include <vector>
 
 #include "ftxui/component/component.hpp"
+#include "ftxui/dom/elements.hpp"
+#include "ftxui/screen/box.hpp"
 
 namespace ftxui {
+struct Event;
 
 /// @brief An horizontal list of elements. The user can navigate through them.
 /// @ingroup component