Add option for Button.

include/ftxui/component/button.hpp

@@ -21,7 +21,9 @@ class ButtonBase : public ComponentBase {
   static ButtonBase* From(Component);
 
   // Constructor.
-  ButtonBase(ConstStringRef label, std::function<void()> on_click, bool border);
+  ButtonBase(ConstStringRef label,
+             std::function<void()> on_click,
+             ConstRef<ButtonOption> option);
   ~ButtonBase() override = default;
 
   // Component implementation.
@@ -31,8 +33,8 @@ class ButtonBase : public ComponentBase {
  private:
   ConstStringRef label_;
   std::function<void()> on_click_;
-  bool border_;
   Box box_;
+  ConstRef<ButtonOption> option_;
 };
 
 }  // namespace ftxui

include/ftxui/component/component.hpp

@@ -26,7 +26,7 @@ std::shared_ptr<T> Make(Args&&... args) {
 
 Component Button(ConstStringRef label,
                  std::function<void()> on_click,
-                 bool border = true);
+                 ConstRef<ButtonOption> = {});
 Component Checkbox(ConstStringRef label, bool* checked);
 Component Input(StringRef content, ConstStringRef placeholder);
 Component Menu(const std::vector<std::wstring>* entries,

include/ftxui/component/component_options.hpp

@@ -14,6 +14,10 @@ struct MenuOption {
   std::function<void()> on_enter = []() {};
 };
 
-};     // namespace ftxui
+struct ButtonOption {
+  bool border = true;
+};
+
+};  // namespace ftxui
 
 #endif /* end of include guard: FTXUI_COMPONENT_COMPONENT_OPTIONS_HPP */