SDL2/dialogs/sdl_selectlist.cpp

#include <cassert>
#include "sdl_selectlist.hpp"
 
static const Uint32 vpadding = 5;
 
SdlSelectList::SdlSelectList(const std::string& title, const std::vector<std::string>& labels)
    : _window(nullptr), _renderer(nullptr)
{
  const size_t widget_height = 50;
  const size_t widget_width = 600;
 
  const size_t total_height = labels.size() * (widget_height + vpadding) + vpadding;
  const size_t height = total_height + widget_height;
  assert(widget_width <= INT32_MAX);
  assert(height <= INT32_MAX);
 
  auto flags = SDL_WINDOW_ALLOW_HIGHDPI | SDL_WINDOW_MOUSE_FOCUS | SDL_WINDOW_INPUT_FOCUS;
  auto rc = SDL_CreateWindowAndRenderer(static_cast<int>(widget_width), static_cast<int>(height),
                                        flags, &_window, &_renderer);
  if (rc != 0)
    widget_log_error(rc, "SDL_CreateWindowAndRenderer");
  else
  {
    SDL_SetWindowTitle(_window, title.c_str());
 
    SDL_Rect rect = { 0, 0, widget_width, widget_height };
    for (auto& label : labels)
    {
      _list.emplace_back(_renderer, label, rect);
      rect.y += widget_height + vpadding;
    }
 
    const std::vector<int> buttonids = { INPUT_BUTTON_ACCEPT, INPUT_BUTTON_CANCEL };
    const std::vector<std::string> buttonlabels = { "accept", "cancel" };
    _buttons.populate(_renderer, buttonlabels, buttonids, widget_width,
                      static_cast<Sint32>(total_height), static_cast<Sint32>(widget_width / 2),
                      static_cast<Sint32>(widget_height));
    _buttons.set_highlight(0);
  }
}
 
SdlSelectList::~SdlSelectList()
{
  _list.clear();
  _buttons.clear();
  SDL_DestroyRenderer(_renderer);
  SDL_DestroyWindow(_window);
}
 
int SdlSelectList::run()
{
  int res = -2;
  ssize_t CurrentActiveTextInput = 0;
  bool running = true;
 
  if (!_window || !_renderer)
    return -2;
  try
  {
    while (running)
    {
      if (!clear_window(_renderer))
        throw;
 
      if (!update_text())
        throw;
 
      if (!_buttons.update(_renderer))
        throw;
 
      SDL_Event event = {};
      SDL_WaitEvent(&event);
      switch (event.type)
      {
        case SDL_KEYDOWN:
          switch (event.key.keysym.sym)
          {
            case SDLK_UP:
            case SDLK_BACKSPACE:
              if (CurrentActiveTextInput > 0)
                CurrentActiveTextInput--;
              else
                CurrentActiveTextInput = _list.size() - 1;
              break;
            case SDLK_DOWN:
            case SDLK_TAB:
              if (CurrentActiveTextInput < 0)
                CurrentActiveTextInput = 0;
              else
                CurrentActiveTextInput++;
              CurrentActiveTextInput = CurrentActiveTextInput % _list.size();
              break;
            case SDLK_RETURN:
            case SDLK_RETURN2:
            case SDLK_KP_ENTER:
              running = false;
              res = static_cast<int>(CurrentActiveTextInput);
              break;
            case SDLK_ESCAPE:
              running = false;
              res = INPUT_BUTTON_CANCEL;
              break;
            default:
              break;
          }
          break;
        case SDL_MOUSEMOTION:
        {
          ssize_t TextInputIndex = get_index(event.button);
          reset_mouseover();
          if (TextInputIndex >= 0)
          {
            auto& cur = _list[TextInputIndex];
            if (!cur.set_mouseover(_renderer, true))
              throw;
          }
 
          _buttons.set_mouseover(event.button.x, event.button.y);
        }
        break;
        case SDL_MOUSEBUTTONDOWN:
        {
          auto button = _buttons.get_selected(event.button);
          if (button)
          {
            running = false;
            if (button->id() == INPUT_BUTTON_CANCEL)
              res = INPUT_BUTTON_CANCEL;
            else
              res = static_cast<int>(CurrentActiveTextInput);
          }
          else
          {
            CurrentActiveTextInput = get_index(event.button);
          }
        }
        break;
        case SDL_QUIT:
          res = INPUT_BUTTON_CANCEL;
          running = false;
          break;
        default:
          break;
      }
 
      reset_highlight();
      if (CurrentActiveTextInput >= 0)
      {
        auto& cur = _list[CurrentActiveTextInput];
        if (!cur.set_highlight(_renderer, true))
          throw;
      }
 
      SDL_RenderPresent(_renderer);
    }
  }
  catch (...)
  {
    return -1;
  }
  return res;
}
 
ssize_t SdlSelectList::get_index(const SDL_MouseButtonEvent& button)
{
  const Sint32 x = button.x;
  const Sint32 y = button.y;
  for (size_t i = 0; i < _list.size(); i++)
  {
    auto& cur = _list[i];
    auto r = cur.rect();
 
    if ((x >= r.x) && (x <= r.x + r.w) && (y >= r.y) && (y <= r.y + r.h))
      return i;
  }
  return -1;
}
 
bool SdlSelectList::update_text()
{
  for (auto& cur : _list)
  {
    if (!cur.update_text(_renderer))
      return false;
  }
 
  return true;
}
 
void SdlSelectList::reset_mouseover()
{
  for (auto& cur : _list)
  {
    cur.set_mouseover(_renderer, false);
  }
}
 
void SdlSelectList::reset_highlight()
{
  for (auto& cur : _list)
  {
    cur.set_highlight(_renderer, false);
  }
}