Added a decorator to prevent selectability

examples/component/selectable_input.cpp

@@ -47,7 +47,7 @@ int main() {
         window(text("Vertical split"), vbox({
                                            LoremIpsum(),
                                            separator(),
-                                           LoremIpsum(),
+                                           LoremIpsum() | unselectable,
                                            separator(),
                                            LoremIpsum(),
                                        })),

include/ftxui/dom/elements.hpp

@@ -113,6 +113,7 @@ Decorator focusPositionRelative(float x, float y);
 Element automerge(Element child);
 Decorator hyperlink(std::string link);
 Element hyperlink(std::string link, Element child);
+Element unselectable(Element child);
 
 // --- Layout is
 // Horizontal, Vertical or stacked set of elements.

src/ftxui/dom/selection.cpp

@@ -5,8 +5,22 @@
 #include "ftxui/dom/selection.hpp"  // for Selection
 #include <algorithm>                // for max, min
 
+#include "ftxui/dom/elements.hpp"        // for Element, inverted
+#include "ftxui/dom/node_decorator.hpp"  // for NodeDecorator
+
 namespace ftxui {
 
+namespace {
+class Unselectable : public NodeDecorator {
+ public:
+  using NodeDecorator::NodeDecorator;
+
+  void Select(Selection& selection) override {
+    // Overwrite the select method to do nothing.
+  }
+};
+}  // namespace
+
 /// @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.
@@ -103,4 +117,11 @@ Selection Selection::SaturateVertical(Box box) {
   return Selection(start_x, start_y, end_x, end_y);
 }
 
+/// @brief Add a filter that will invert the foreground and the background
+/// colors.
+/// @ingroup dom
+Element unselectable(Element child) {
+  return std::make_shared<Unselectable>(std::move(child));
+}
+
 }  // namespace ftxui