FTXUI/ftxui/src/ftxui/component/menu.cpp

#include "ftxui/component/menu.hpp"
#include <algorithm>

namespace ftxui {
namespace component {

Menu::Menu(Delegate* delegate) : Component(delegate) {}

dom::Element Menu::Render() {
  using namespace dom;
  std::vector<Element> elements;
  bool focused = Focused();
  for (size_t i = 0; i < entries.size(); ++i) {
    if (size_t(selected) == i) {
      if (focused)
        elements.push_back(inverted(text(L"> " + entries[i])));
      else
        elements.push_back(bold(text(L"> " + entries[i])));
    }
    else {
      elements.push_back(text(L"  " + entries[i]));
    }
  }
  return vbox(std::move(elements));
}

bool Menu::Event(int key) {
  if (!Focused())
    return false;

  int new_selected = selected;
  if (key == 65 || key == 'k')
    new_selected--;
  if (key == 66 || key == 'j')
    new_selected++;
  new_selected = std::max(0, std::min(int(entries.size())-1, new_selected));

  if (selected != new_selected) {
    selected = new_selected;
    on_change();
    return true;
  }

  if (key == 10) {
    on_enter();
    return true;
  }

  return false;
}

}  // namespace component
}  // namespace ftxui