[MS Smartphone]Double Buffering Using Native C Code

void CreateGrphicMenuWin()
{ 
 WNDCLASS wc; 
 RECT rect;
 ZeroMemory(&wc, sizeof(wc));
 ...

 wc.lpfnWndProc = (WNDPROC)MenuWinProc;
 ...
 //RegisterClass(&wc) 
 //CreateWindow
 //ShowWindow
 //UpdateWindow

}

BOOL CALLBACK MenuWinProc(HWND hwnd, UINT msg, WPARAM wParam, LPARAM lParam)
{
 LRESULT lResult = 0;
 PAINTSTRUCT ps;
 
 switch(msg)
 {
 ...
 case WM_PAINT:
  {   
   HDC hDC    = BeginPaint(hwnd,&ps);   
   DrawGraphicMenuBar(hwnd,hDC); 
   EndPaint (hwnd, &ps);
  }
  return 0;
 ...

 } 
 return (DefWindowProc(hwnd, msg, wParam, lParam));
}

void DrawGraphicMenuBar(HWND hwnd, HDC hDC)
{
 HDC   hMemDC  = CreateCompatibleDC(hDC);
 HDC   hDrawDC = CreateCompatibleDC(hDC);
 
 HBITMAP   hBitmap,  hOldbmp;
 HBITMAP   hBgTitle, hPlay, hStop;
 HBITMAP   hOldBgTitle, hOldPlay, hOldStop;

 hBitmap = CreateCompatibleBitmap(hDC, PHONEWIDTH, MENUHEIGHT);
 hOldbmp = (HBITMAP)SelectObject(hMemDC, hBitmap);
 
 hBgTitle = LoadBitmap(context->hInst, MAKEINTRESOURCE(IDB_SBGTITLE));
 hOldBgTitle = (HBITMAP) SelectObject(hDrawDC, hBgTitle);   
 BitBlt(hMemDC,  0, 0, PHONEWIDTH, MENUHEIGHT, hDrawDC, 0, 0, SRCCOPY);
 SelectObject(hDrawDC, hOldBgTitle);        
 DeleteObject(hBgTitle);

 hPlay = LoadBitmap(context->hInst, MAKEINTRESOURCE(IDB_SPLAY));
 hOldPlay = (HBITMAP) SelectObject(hDrawDC, hPlay);   
 BitBlt(hMemDC, LEFTSPACE, TOPSPACE,  PLAYPAUSEWIDTH, ICONHEIGHT, hDrawDC, 0, 0, SRCCOPY);
 SelectObject(hDrawDC, hOldPlay);
 DeleteObject(hPlay);

 hStop = LoadBitmap(context->hInst, MAKEINTRESOURCE(IDB_SSTOP));
 hOldStop = (HBITMAP) SelectObject(hDrawDC, hStop);   
 BitBlt(hMemDC, PLAYPAUSEWIDTH+LEFTSPACE, TOPSPACE,  STOPWIDTH, ICONHEIGHT, hDrawDC, 0, 0, SRCCOPY);
 SelectObject(hDrawDC, hOldStop);
 DeleteObject(hStop);

        BitBlt(hDC,  0, 0, PHONEWIDTH, MENUHEIGHT, hMemDC, 0, 0, SRCCOPY);////
       
 SelectObject(hMemDC, hOldbmp);  
 DeleteObject(hBitmap);    
 
 DeleteDC(hMemDC);     
 DeleteDC(hDrawDC);     
}