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winapiassemblymasm32

Win32 API: Child windows with different images

I was given a assignment at the university: to write a game in MASM. I chose a game the type of "three in a row". Objects in the game are some sweets: ice cream, lollipop, etc. But I have a problem. I don't know how to make child windows with different images. I've tried, but nothing is working. Maybe someone knows how to implement this? Any help is appreciated. Even in C/C++. I would be glad if someone just explain to me in words how to do it. The main thing for me is to understand the concept.

I have

enter image description here

But I need this

enter image description here

Solution

  • Of course you have JUST ONE IMAGE, because hBit IS A GLOBAL VARIABLE, hBit is overwritten in all calls to CreateSweetsWindow, in fact: it retains last image loaded.

    I suggest you add hBit to SweetsWindowStruct struct:

    SweetsWindowStruct struct
    stype   SWEETSTYPE     ?
    sweetsID DWORD         ?
    hBit HBITMAP           ?
SweetsWindowStruct ends

    And remove global hBit (line 44 in your sweets.asm file), you must change WM_PAINT code like this:

     .elseif [iMsg] == WM_PAINT

    invoke BeginPaint, [hwnd], addr ps
    mov [hdc], eax

    invoke CreateCompatibleDC, hdc
    mov [hMemDC], eax

    SweetsWindowStruct *sws;// sorry show you in c++
    sws = (SweetsWindowStruct*)GetWindowLong(hwnd, GWL_USERDATA);
    HBITMAP hBit = sws->hBit;

    invoke SelectObject, hMemDC, [hBit]
    mov [oldDC], eax

    Other issue: i think you have a error, where you say:

    invoke SetWindowLong, [hwnd], 0, addr [sws]

    it must be:

    invoke SetWindowLong, [hwnd], GWL_USERDATA, addr [sws]

    Please check that