stb_hello.cc

来自「Linux嵌入式设计配套光盘,学习嵌入式设计可参考」· CC 代码 · 共 103 行

/****************************************************************************
 * stb_hello.cc
 *
 * A simple demonstration UI using STBmenu and SDL.
 ****************************************************************************/
#include <stdio.h>
#include <stdlib.h>

#include "SDL.h"                /* All SDL App's need this */
#include "STBmenu.h"

#define BLACK      0x000000
#define LIGHT_BLUE 0x8080FF
#define CYAN       0x00FFFF
#define YELLOW     0xFFFF00

int enableQuit = 0;

/****************************************************************************
 * callbacks
 ****************************************************************************/
static void Hello(InputClass* const widget)
{
  printf("Hello, world!\n");
}

static void QuitApplication(InputClass* const widget)
{
  enableQuit = 1;
}

/****************************************************************************
 * main
 ****************************************************************************/
int main(int argc, char *argv[]) {
  SDL_Event event;

  // Allocate the persistent (static) objects required for the menu.  Always
  // allocate the Menu first, since this initializes the video context.

  // Menu: Provide number of pages, as well as width, height, bpp, and flags.
  Menu* menu = new Menu(1, 640, 480, 8);

  // A single page: Provide number rows, columns, background surface
  Surface background(640,480,BLACK);
  Page page(2, 1, background);
  menu->AttachPage(0, page); // Provide page number and page

  // The Hello button widget
  Font font("/usr/local/share/fonts/bitstream/VeraBI.ttf",42);

  Surface nfHello(font,CYAN,  "Hello");
  Surface fHello (font,YELLOW,"Hello <");
  Button helloButton(nfHello,fHello);
  WButton wHello(helloButton,Hello,NULL);
  page.AttachWidget(0,0,250,200,wHello); // Provide row, col, x, and y

  // The Exit button widget
  Surface nfExit (font,CYAN,  "Exit");
  Surface fExit  (font,YELLOW,"Exit <");
  Button exitButton (nfExit, fExit);
  WButton wExit (exitButton, QuitApplication,NULL);
  page.AttachWidget(1,0,250,260,wExit);

  // Select the starting cursor position on each page. Finish with the first
  // page to display, then display it.
  menu->SetCursor(0, 0, 0);
  menu->DisplayCurrentPage();

  enableQuit = 0;
  while(!enableQuit){

    SDL_WaitEvent(&event);

    switch(event.type){
      case SDL_KEYDOWN:
        switch(event.key.keysym.sym){
          // A fallback for a graceful exit
          case SDLK_ESCAPE:
            enableQuit = 1;
            break;
          case SDLK_LEFT:
            menu->CursorLeft();
            break;
          case SDLK_RIGHT:
            menu->CursorRight();
            break;
          case SDLK_UP:
            menu->CursorUp();
            break;
          case SDLK_DOWN:
            menu->CursorDown();
            break;
          case SDLK_RETURN:
            menu->Activate();
            break;
        }
        break;
    }
    menu->Update();
  }
}