Windows 編程[17] – 更換菜單: LoadMenu、DestroyMenu、SetMenu

本例:

本例在資源檔中備有兩組菜單, 程式實現運行時切換.

本例使用的資源檔(TestRes.rc):

MyMenu1 MENUEXBEGIN  MENUITEM "Open"    ,101  MENUITEM "Edit"    ,102  MENUITEM "Help"    ,103  MENUITEM "Chinese" ,104 ,MFT_RIGHTJUSTIFYENDMyMenu2 MENUEXBEGIN  MENUITEM "開啟"    ,201  MENUITEM "編輯"    ,202  MENUITEM "協助"    ,203  MENUITEM "English" ,204 ,MFT_RIGHTJUSTIFYEND

本例代碼檔案:

program Project1;{$R 'TestRes.res' 'TestRes.rc'}uses  Windows, Messages;{收到 WM_COMMAND 訊息時需要做的工作}procedure OnCommand(h: HWND; wParam: Integer);var  hm : HMENU;begin  case wParam of    104,204: begin   {104 和 204 是在資源檔中指定的菜單標識}      if LoWord(wParam) = 104 then        hm := LoadMenu(HInstance, 'MyMenu2')      else        hm := LoadMenu(HInstance, 'MyMenu1');      DestroyMenu(GetMenu(h));      SetMenu(h, hm);      DrawMenuBar(h);    end;  end;end;function WndProc(wnd: HWND; msg: UINT; wParam: Integer; lParam: Integer): Integer; stdcall;begin  Result := 0;  case msg of    WM_COMMAND : OnCommand(wnd, wParam); {收到 WM_COMMAND 訊息後調用 OnCommand 過程}    WM_DESTROY : PostQuitMessage(0);  else    Result := DefWindowProc(wnd, msg, wParam, lParam);  end;end;function RegMyWndClass: Boolean;var  cls: TWndClass;begin  cls.style         := CS_HREDRAW or CS_VREDRAW;  cls.lpfnWndProc   := @WndProc;  cls.cbClsExtra    := 0;  cls.cbWndExtra    := 0;  cls.hInstance     := HInstance;  cls.hIcon         := 0;  cls.hCursor       := LoadCursor(0, IDC_ARROW);  cls.hbrBackground := HBRUSH(COLOR_WINDOW + 1);  cls.lpszMenuName  := 'MyMenu1';  cls.lpszClassName := 'MyWnd';  Result := RegisterClass(cls)  0;end;{程式入口}const  tit = 'New Form';  ws = WS_OVERLAPPEDWINDOW;  x = 100; y = 100; w = 300; h = 180;var  hWnd: THandle;  Msg : TMsg;begin  RegMyWndClass;  hWnd := CreateWindow('MyWnd', tit, ws, x, y, w, h, 0, 0, HInstance, nil);  ShowWindow(hWnd, SW_SHOWNORMAL);  UpdateWindow(hWnd);  while(GetMessage(Msg, 0, 0, 0)) do  begin    TranslateMessage(Msg);    DispatchMessage(Msg);  end;end.