第十章 菜单及其它资源part3

较难的一种菜单定义方法

在程序的资源描述文件中定义菜单，通常是在您的窗口中添加菜单的最简单方法，但不是唯一的方法。

如果您没有使用资源描述档，那么可以使用CreateMenu和AppendMenu两个函数在程序中建立菜单。

在您定义完菜单后，您可以将菜单句柄发送给CreateWindow或者使用SetMenu来设定窗口的菜单。

hMenuPopup = CreateMenu () ;

AppendMenu(hMenuPopup, MF_STRING, IDM_FILE_NEW, "&New");  

AppendMenu(hMenuPopup, MF_STRING, IDM_FILE_OPEN, "&Open...");  

下面的代码是浮动弹出式菜单的

#include <windows.h> #include "resource.h" LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM); HINSTANCE hInst ; TCHAR szAppName[] = TEXT("PopMenu"); int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow){ HWND hwnd; MSG msg; WNDCLASS wndclass; wndclass.style = CS_HREDRAW | CS_VREDRAW ; wndclass.lpfnWndProc = WndProc ; wndclass.cbClsExtra = 0 ; wndclass.cbWndExtra = 0 ; wndclass.hInstance = hInstance ; wndclass.hIcon = LoadIcon(NULL,szAppName); wndclass.hCursor = LoadCursor(NULL, IDC_ARROW); wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); wndclass.lpszMenuName = NULL; wndclass.lpszClassName = szAppName; if (!RegisterClass (&wndclass)) { MessageBox(NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR); return 0; } hInst = hInstance;hwnd = CreateWindow(szAppName, TEXT("Popup Menu Demonstration"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL);ShowWindow(hwnd, iCmdShow); UpdateWindow(hwnd);while(GetMessage(&msg, NULL, 0, 0)) { TranslateMessage(&msg); DispatchMessage(&msg); } return msg.wParam; } LRESULT CALLBACK WndProc( HWND hwnd, UINT message, WPARAM wParam,LPARAM lParam) { static HMENU hMenu ; static int idColor [5] = {WHITE_BRUSH, LTGRAY_BRUSH, GRAY_BRUSH, DKGRAY_BRUSH, BLACK_BRUSH } ; static int iSelection = IDM_BKGND_WHITE; POINT point; switch (message) { case WM_CREATE://POPMENU取得此弹出式菜单的句柄，就是带//有文字「MyMenu」的那个弹出式菜单hMenu = LoadMenu(hInst, MAKEINTRESOURCE(IDR_MENU3)); hMenu = GetSubMenu(hMenu, 0); return 0; case WM_RBUTTONUP://POPMENU提供了鼠标指针的位置，将此位置转换为//屏幕坐标，再将坐标值传递给TrackPopupMenupoint.x = LOWORD(lParam); point.y = HIWORD(lParam);//该函数将指定点的用户坐标转换成屏幕坐标。ClientToScreen(hwnd, &point); //函数在指定位置显示快捷菜单，并跟踪菜单项的选择。//快捷菜单可出现在屏幕上的任何位置TrackPopupMenu(hMenu, TPM_RIGHTBUTTON, point.x, point.y, 0, hwnd, NULL) ; return 0 ; case WM_COMMAND: switch (LOWORD (wParam)) { case IDM_FILE_NEW: case IDM_FILE_OPEN: case IDM_FILE_SAVE: case IDM_FILE_SAVE_AS: case IDM_EDIT_UNDO: case IDM_EDIT_CUT: case IDM_EDIT_COPY: case IDM_EDIT_PASTE: case IDM_EDIT_CLEAR: MessageBeep(0); return 0 ; case IDM_BKGND_WHITE: // Note: Logic below case IDM_BKGND_LTGRAY: // assumes that IDM_WHITE case IDM_BKGND_GRAY: // through IDM_BLACK are case IDM_BKGND_DKGRAY: // consecutive numbers in case IDM_BKGND_BLACK: // the order shown here. CheckMenuItem(hMenu, iSelection, MF_UNCHECKED) ; iSelection = LOWORD (wParam) ; CheckMenuItem(hMenu, iSelection, MF_CHECKED) ; SetClassLong(hwnd, GCL_HBRBACKGROUND, (LONG) GetStockObject(idColor[LOWORD(wParam) - IDM_BKGND_WHITE])) ; InvalidateRect (hwnd, NULL, TRUE); return 0 ; case IDM_APP_ABOUT: MessageBox(hwnd, TEXT("Popup Menu Demonstration Program/n") TEXT ("(c) Charles Petzold, 1998"), szAppName, MB_ICONINFORMATION | MB_OK); return 0; case IDM_APP_EXIT: SendMessage(hwnd, WM_CLOSE, 0, 0) ; return 0 ; case IDM_APP_HELP: MessageBox (hwnd, TEXT ("Help not yet implemented!"), szAppName, MB_ICONEXCLAMATION | MB_OK) ; return 0 ; } break ; case WM_DESTROY: PostQuitMessage(0);return 0;} return DefWindowProc(hwnd, message, wParam, lParam) ; }  

使用系统菜单

AppendMenu在菜单尾部添加一个新的菜单项目

DeleteMenu删除菜单中一个现有的菜单项并清除该项目

InsertMenu在菜单中插入一个新项目

ModifyMenu修改一个现有的菜单项目

RemoveMenu从菜单中移走某一项目

DeleteMenu清除弹出式菜单，但RemoveMenu不清除它。

其它菜单命令 

当您改变顶层菜单项时，直到Windows重画菜单列时才显示所做的改变。您可以通过下列呼叫来强迫执行菜单更新： DrawMenuBar (hwnd) ;

hMenuPopup = GetSubMenu (hMenu, iPosition) ; //获得弹出式菜单的句柄 
iCount = GetMenuItemCount (hMenu) ;//获得顶层菜单或者弹出式菜单中目前的项数

id = GetMenuItemID (hMenuPopup, iPosition) ;   //取得弹出式菜单项的菜单ID

CheckMenuItem (hMenu, id, iCheck) ;  //取消选中弹出式菜单中的某一项

iFlags = GetMenuState (hMenu, id, iFlag) ;    //菜单项目前的属性是什么

DestroyMenu (hMenu) ; //清除菜单

#include <windows.h>//三个菜单ID在POORMENU.C的开始部分定义#define IDM_SYS_ABOUT 1 #define IDM_SYS_HELP 2 #define IDM_SYS_REMOVE 3 LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM); static TCHAR szAppName[] = TEXT ("PoorMenu"); int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance, PSTR szCmdLine, int iCmdShow) { HMENU hMenu; HWND hwnd; MSG msg; WNDCLASS wndclass; wndclass.style = CS_HREDRAW | CS_VREDRAW ; wndclass.lpfnWndProc = WndProc ; wndclass.cbClsExtra = 0 ; wndclass.cbWndExtra = 0 ; wndclass.hInstance = hInstance ; wndclass.hIcon = LoadIcon(NULL, IDI_APPLICATION) ; wndclass.hCursor = LoadCursor(NULL, IDC_ARROW); wndclass.hbrBackground = (HBRUSH)GetStockObject(WHITE_BRUSH); wndclass.lpszMenuName = NULL; wndclass.lpszClassName = szAppName; if (!RegisterClass (&wndclass)) { MessageBox ( NULL, TEXT("This program requires Windows NT!"), szAppName, MB_ICONERROR);return 0 ;}hwnd = CreateWindow(szAppName, TEXT ("The Poor-Person's Menu"), WS_OVERLAPPEDWINDOW, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, CW_USEDEFAULT, NULL, NULL, hInstance, NULL); //POORMENU得到一个系统菜单的句柄//该函数允许应用程序为复制或修改而访问窗口菜单(系统菜单或控制菜单)hMenu = GetSystemMenu(hwnd, FALSE);//添加分隔条AppendMenu(hMenu, MF_SEPARATOR, 0, NULL); AppendMenu(hMenu, MF_STRING, IDM_SYS_ABOUT, TEXT("About...")); AppendMenu(hMenu, MF_STRING, IDM_SYS_HELP, TEXT("Help...")); AppendMenu(hMenu, MF_STRING, IDM_SYS_REMOVE, TEXT("Remove Additions"));ShowWindow (hwnd, iCmdShow) ; UpdateWindow (hwnd) ; while (GetMessage(&msg, NULL, 0, 0)) { TranslateMessage(&msg); DispatchMessage(&msg); } return msg.wParam; } LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM wParam,LPARAM lParam) { //窗口某单最初包含的菜单项有多种标识符值，如SC_CLOSE，SC_MOVE和SC_SIZE。//窗口菜单上的菜单项发送WM_SYSCOMMAND消息。switch (message) { //必须把其它的//WM_SYSCOMMAND消息发送给DefWindowProc。如果您不这样做，那么实际上是禁用//了系统菜单上的所有正常选项。case WM_SYSCOMMAND:switch (LOWORD(wParam)) { case IDM_SYS_ABOUT: MessageBox(hwnd, TEXT("A Poor-Person's Menu Program/n") TEXT("(c) Charles Petzold, 1998"), szAppName, MB_OK | MB_ICONINFORMATION); return 0 ;case IDM_SYS_HELP: MessageBox(hwnd, TEXT("Help not yet implemented!"), szAppName, MB_OK | MB_ICONEXCLAMATION) ; return 0;case IDM_SYS_REMOVE://选择「Remove Additions」菜单项将使//POORMENU删除这些附加的菜单项，这只要把第二个参数设定为TRUE，再次呼叫//GetSystemMenu即可：GetSystemMenu(hwnd, TRUE); return 0 ; } break;case WM_DESTROY: PostQuitMessage(0); return 0; } return DefWindowProc(hwnd, message, wParam, lParam) ;}