catch_event.cpp

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#include <functional>  // for function
#include <memory>  // for __shared_ptr_access, __shared_ptr_access<>::element_type, shared_ptr
#include <utility>  // for move
 
#include "ftxui/component/component.hpp"  // for Component, Make, CatchEvent
#include "ftxui/component/component_base.hpp"  // for ComponentBase
#include "ftxui/component/event.hpp"           // for Event
 
namespace ftxui {
 
class CatchEventBase : public ComponentBase {
 public:
  // Constructor.
  CatchEventBase(std::function<bool(Event)> on_event)
      : on_event_(std::move(on_event)) {}
 
  // Component implementation.
  bool OnEvent(Event event) override {
    if (on_event_(event))
      return true;
    else
      return ComponentBase::OnEvent(event);
  }
 
 protected:
  std::function<bool(Event)> on_event_;
};
 
/// @brief Return a component, using |on_event| to catch events. This function
/// must returns true when the event has been handled, false otherwise.
/// @param child The wrapped component.
/// @param on_event The function drawing the interface.
/// @ingroup component
///
/// ### Example
///
/// ```cpp
/// auto screen = ScreenInteractive::TerminalOutput();
/// auto renderer = Renderer([] {
///   return text("My interface");
/// });
/// screen.Loop(renderer);
/// ```
Component CatchEvent(Component child,
                     std::function<bool(Event event)> on_event) {
  auto out = Make<CatchEventBase>(std::move(on_event));
  out->Add(std::move(child));
  return out;
}
 
}  // namespace ftxui
 
// 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.