程式語言 - ObjAsm - Single Document Interface (SDI) - Handle Event

參考資訊：
https://github.com/ObjAsm
https://objasm.x10host.com/index.htm

main.asm

%include @Environ(OBJASM_PATH)\Code\Macros\Model.inc
SysSetup OOP, WIN32, ANSI_STRING
      
MakeObjects Primer, Stream, WinPrimer, Window, WinApp, SdiApp
  
    .const
CStr szName, "main"
 
Object MyApp, , SdiApp
    RedefineMethod Init
    VirtualEvent OnPaint, WM_PAINT
  
    DefineVariable wndClass, WNDCLASS, {0}
ObjectEnd
 
    .code    
Method MyApp.Init, uses esi
    SetObject esi
    ACall esi.Init
 
    m2m [esi].wndClass.lpfnWndProc, $MethodAddr(MyApp.WndProc)
    m2m [esi].wndClass.lpszClassName, offset szName
    invoke RegisterClass, addr [esi].wndClass
 
    invoke CreateWindowEx, WS_EX_LEFT, offset szName, offset szName,
        WS_OVERLAPPEDWINDOW or WS_VISIBLE, 0, 0, 300, 300, NULL, NULL, NULL, pSelf
    m2m [esi].hWnd, eax
MethodEnd

Method MyApp.OnPaint, uses esi, wParam:WPARAM, lParam:LPARAM
    local hDC:HDC
    local PS:PAINTSTRUCT

    SetObject esi 
    mov hDC, $invoke(BeginPaint, [esi].hWnd, addr PS) 
    invoke EndPaint, [esi].hWnd, addr PS
MethodEnd

start proc
    SysInit
      
    OCall $ObjTmpl(MyApp)::MyApp.Init
    OCall $ObjTmpl(MyApp)::MyApp.Run
    OCall $ObjTmpl(MyApp)::MyApp.Done
      
    SysDone
    invoke ExitProcess, 0
start endp
      
end

完成