WM_PAINT

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sswift

I've been trying to figure out how bitmaps are drawn in Windows for a few days now, and I found this code:

case WM_PAINT:
{
    HDC dc = GetDC(hWnd);
    HDC memDC ;
    HBITMAP memBitmap = LoadBitmap(hInstance,MAKEINTRESOURCE(IDB_BITMAP_ONE));
    HBITMAP oldBitmap ;

    memDC = CreateCompatibleDC(dc) ;
    oldBitmap = (HBITMAP)SelectObject(memDC,memBitmap) ;

    BITMAP bm;
    GetObject(memBitmap, sizeof(BITMAP), (LPVOID)&bm);
    if (memDC != NULL)
    {
        StretchBlt(dc,0, 0, m_nClientWidth, m_nClientHeight, memDC, 0, 0, bm.bmWidth, bm.bmHeight, SRCCOPY) ;
    }
    SelectObject(memDC,oldBitmap) ;
}
break;
    
you need to provide this code with the
size of the window, put this code
somewhere under before this code after the.

    RECT rect;
    GetClientRect(hWnd,&rect);
    m_nClientWidth = rect.right-rect.left;
    m_nClientHeight = rect.bottom - rect.top;

Also the code assummes that you have a bitmap with name IDB_BITMAP_ONE to be drawn.

Don't tell me that in order to draw a bitmap in a window, I have to redraw it every single time my app gets a WM_PAINT message!

I obviously can't do that in Blitzplus, because it intercepts all the messages, and automatically runs a program in a special loop that disallows drawing commands whenever someone for example, moves a scrollbar!

Augh... someone please tell me this is not the case and that there is an object I can create in a window like a button that is always there and that I don't have to redraw manually!