Adding Palette Message Handlers

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The following example illustrates simple message handlers for the WM_PALETTECHANGED and WM_QUERYNEWPALETTE messages. The example uses the DrawDibRealize function to process the WM_QUERYNEWPALETTE message.

Your application should respond to the WM_QUERYNEWPALETTE message by invalidating the destination window to let the DrawDibDraw function redraw an image. You should respond to the WM_PALETTECHANGED message by using the DrawDibRealize function to realize the palette.

case WM_PALETTECHANGED: 
    if ((HWND)wParam == hwnd) 
        break; 
case WM_QUERYNEWPALETTE: 
    hdc = GetDC(hwnd); 
    f = DrawDibRealize(hdd, hdc, FALSE) > 0; 
    ReleaseDC(hwnd, hdc); 
    if (f) 
        InvalidateRect(hwnd, NULL, TRUE); 
    break;