參考資訊:
https://masm32.com/board/index.php
https://www.nasm.us/xdoc/2.13rc9/html/nasmdoc0.html
當視窗有事件需要被處理時,系統會透過呼叫註冊的Callback副程式來處理,而這個Callback副程式就是在註冊Class時,設定給lpfnWndProc的事件處理副程式,因此,當這個事件處理副程式被呼叫時,可以處理自己感興趣的事件,而其餘事件則交給系統處理(透過呼叫DefWindowProc()),需要注意的是,例如:WM_CLOSE,就必須由該視窗自己處理,因為系統無法知道還有哪些額外的資源需要被釋放掉
main.asm
%include "c:\\nasmx\\inc\\nasmx.inc" %include "c:\\nasmx\\inc\\win32\\windows.inc" %include "c:\\nasmx\\inc\\win32\\user32.inc" %include "c:\\nasmx\\inc\\win32\\kernel32.inc" entry start section .data szName declare(NASMX_TCHAR) NASMX_TEXT("main"),0 CommandLine dd 0 hInstance dd 0 NASMX_ISTRUC msg, MSG NASMX_IENDSTRUC NASMX_ISTRUC wndClass, WNDCLASS NASMX_IENDSTRUC section .text proc WndProc, dword hWnd, uint_t uMsg, dword wParam, dword lParam locals none switch dword [argv(.uMsg)] case dword WM_CLOSE invoke DestroyWindow, [argv(.hWnd)] break case dword WM_DESTROY invoke PostQuitMessage, 0 break default invoke DefWindowProc, [argv(.hWnd)], [argv(.uMsg)], [argv(.wParam)], [argv(.lParam)] endswitch endproc proc WinMain, dword hInst, dword hPrevInst, dword CmdLine, dword CmdShow locals none mov dword [wndClass + WNDCLASS.lpfnWndProc], WndProc mov dword [wndClass + WNDCLASS.lpszClassName], szName invoke RegisterClass, wndClass invoke CreateWindowEx, WS_EX_LEFT, szName, szName, \ WS_OVERLAPPEDWINDOW | WS_VISIBLE, 0, 0, 300, 300, NULL, NULL, NULL, NULL do invoke DispatchMessage, msg invoke GetMessage, msg, NULL, NULL, NULL while eax, !=, 0 mov eax, dword [msg + MSG.wParam] endproc proc start, dword argc, dword argv locals none invoke GetModuleHandle, NULL mov [hInstance], eax invoke GetCommandLine, NULL mov [CommandLine], eax invoke WinMain, [hInstance], NULL, [CommandLine], SW_SHOWNORMAL invoke ExitProcess, NULL endproc
Line 23~29:關閉視窗的順序為:主視窗收到WM_CLOSE事件時,呼叫DestroyWindow(),DestroyWindow()會自動將子視窗的相關資源也一併釋放掉(包含Resource描述的資源),系統接著會發送WM_DESTROY事件給主視窗,待主視窗收到WM_DESTROY事件時,呼叫PostQuitMessage()結束視窗,值得注意的地方是,SendMessage()是屬於Block方式呼叫(必須等待動作執行完畢才返回),而PostQuitMessage()則是Non-block方式呼叫
Line 30~31:其餘事件由系統代為處理
完成