孙鑫VC++深入详解:Lesson6 Part6--- 电话本示例程序 动态添加子菜单 框架类窗口截获命令消息

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一. 电话本设计思路:
a. 在Veiw类中用 OnChar()响应客户区的输入 如 "Weixin 2666777",用空格隔开名称与电话
b. 收到回车键时把每行输入保存到m_strLine,和m_strArray数组中,m_strArray要定义成public,因为MainFrame中要用
c. 用"Weixin"创建动态子菜单.
d. 响应菜单COMMAND,把保存在m_strArray数组中的电话输出.

二. 知识点
1.用到的函数 DrawMenuBar(),这是更新菜单条
2.CStringArray m_strArray  这定义一个CString类的数组:
  如增加一个CString元素m_strArray.Add(m_strLine)
  获取第一个CString元素m_strArray.GetAt(0)
  很方便,自动扩充

3. m_strLine.Empty(),要多使用Empty(),不要老是搞m_strLine=""这种写法.

4 用一个投机取巧的方法去创建动态子菜单的响应函数
    用资源编辑器手工编辑几个静态菜单,用ClassWizard很方便的就能添加菜单项的COMMAND函数
    然后在资源编辑器中把这几个子菜单删除,他们的COMMAND消息响应函数就留下来了.
    不要忘记在resource.h中定义每个子菜单项的ID宏,因为静态子菜单的ID都是在resource.rc文件中,子菜单被删除了
     他们的ID就没有了,所以要去resource.h中为动态菜单添加ID宏.
    
    代码:
    

 //{
    {AFX_MSG_MAP(CMenu2View) //宏注释之间放的是MFC ClassWizard生成的消息映射宏;ON_WM_CHAR() //不是ClassWizard的宏不要放在这之间//}}AFX_MSG_MAP // 否则会在编译时被MFC删除// 投机取巧用静态子菜单的ClassWizard为我们创建的宏移出来,放在下面.不要放在宏注释之间ON_COMMAND(IDM_PHONE1, OnPhone1)ON_COMMAND(IDM_PHONE2, OnPhone2)ON_COMMAND(IDM_PHONE3, OnPhone3)ON_COMMAND(IDM_PHONE4, OnPhone4)

在CMenu2View中处理的代码:

// Menu2View.cpp : implementation of the CMenu2View class //#include "stdafx.h" #include "Menu2.h"#include "Menu2View.h"#ifdef _DEBUG #define new DEBUG_NEW #undef THIS_FILE static char THIS_FILE[] = __FILE__; #endif/ // CMenu2ViewIMPLEMENT_DYNCREATE(CMenu2View, CView)BEGIN_MESSAGE_MAP(CMenu2View, CView)//{
    {AFX_MSG_MAP(CMenu2View) //宏注释之间放的是MFC ClassWizard生成的消息映射宏;ON_WM_CHAR() //不是ClassWizard的宏不要放在这之间//}}AFX_MSG_MAP // 否则会在编译时被MFC删除// 投机取巧用静态子菜单的ClassWizard为我们创建的宏移出来,放在下面.不要放在宏注释之间ON_COMMAND(IDM_PHONE1, OnPhone1)ON_COMMAND(IDM_PHONE2, OnPhone2)ON_COMMAND(IDM_PHONE3, OnPhone3)ON_COMMAND(IDM_PHONE4, OnPhone4)// Standard printing commandsON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview) END_MESSAGE_MAP()/ // CMenu2View construction/destructionCMenu2View::CMenu2View() {// TODO: add construction code herem_nIndex = -1;m_strLine ="";}CMenu2View::~CMenu2View() { }BOOL CMenu2View::PreCreateWindow(CREATESTRUCT& cs) {// TODO: Modify the Window class or styles here by modifying// the CREATESTRUCT csreturn CView::PreCreateWindow(cs); }/ // CMenu2View drawingvoid CMenu2View::OnDraw(CDC* pDC) {CMenu2Doc* pDoc = GetDocument();ASSERT_VALID(pDoc);// TODO: add draw code for native data here }/ // CMenu2View printingBOOL CMenu2View::OnPreparePrinting(CPrintInfo* pInfo) {// default preparationreturn DoPreparePrinting(pInfo); }void CMenu2View::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/) {// TODO: add extra initialization before printing }void CMenu2View::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/) {// TODO: add cleanup after printing }/ // CMenu2View diagnostics#ifdef _DEBUG void CMenu2View::AssertValid() const {CView::AssertValid(); }void CMenu2View::Dump(CDumpContext& dc) const {CView::Dump(dc); }CMenu2Doc* CMenu2View::GetDocument() // non-debug version is inline {ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CMenu2Doc)));return (CMenu2Doc*)m_pDocument; } #endif //_DEBUG/ // CMenu2View message handlersvoid CMenu2View::OnChar(UINT nChar, UINT nRepCnt, UINT nFlags) {// TODO: Add your message handler code here and/or call defaultCClientDC dc(this);static UINT nID =1;if(0x0d==nChar) //回车键{if(0==++m_nIndex) //第一次输入回车键{// 先在类CMenu2View中增加一个成员变量CMenu m_menu m_menu.CreatePopupMenu();//初始化,创建一个空的菜单//菜单依附于框架类而不是视图View类,先用 GetParent()获得指向框架的指针GetParent()->GetMenu()->AppendMenu(MF_POPUP,(UINT)m_menu.m_hMenu,"PhoneBook"); GetParent()->DrawMenuBar(); //菜单有更改是,调用它来更新菜单}// m_menu.AppendMenu(MF_STRING,nID++,m_strLine.Left(m_strLine.Find(' ')));//这里有个缺点是如果没有输入空格,将会得到一个空字符串m_menu.AppendMenu(MF_STRING,IDM_PHONE1+m_nIndex,m_strLine.Left( m_strLine.Find(' ')==-1?m_strLine.GetLength():m_strLine.Find(' ') ));m_strArray.Add(m_strLine);m_strLine.Empty(); Invalidate(true);// true---擦除客户区上的内容}else{m_strLine +=nChar;dc.TextOut(0,0,m_strLine); }CView::OnChar(nChar, nRepCnt, nFlags); }void CMenu2View::OnPhone1() {// TODO: Add your command handler code hereCClientDC dc(this);dc.TextOut(0,0,m_strArray.GetAt(0));}void CMenu2View::OnPhone2() {// TODO: Add your command handler code hereCClientDC dc(this);dc.TextOut(0,0,m_strArray.GetAt(1));}void CMenu2View::OnPhone3() {// TODO: Add your command handler code hereCClientDC dc(this);dc.TextOut(0,0,m_strArray.GetAt(2));}void CMenu2View::OnPhone4() {// TODO: Add your command handler code hereCClientDC dc(this);dc.TextOut(0,0,m_strArray.GetAt(3));} 

中用到了属于CMenu2Doc的一个类型CMenu2Doc* GetDocument().....解决办法就是在Menu2View.h包含Menu2Doc.h,或者在MainFrm.cpp把2者都包含了:Menu2Doc.h和Menu2View.h,注意是#include"Menu2Doc.h"在上先包含.

(4)CMenu2View view; 这么搞是不行的,因为:
虽然view的确是一个CMenu2View的对象,照这么定义的话, CMenu2View X1,X2,X3,X4; 这些X1,X2,X3,X4也都是CMenu2View的对象. 但是这些对象都不是那个与本应用程序的框架类CMainFrame关联了的CMenu2View对象.
注意:由MFC向导生成的单文档应用程序,生成了5个类AboutDlg,CMainFrame,CMenu2App,CMenu2Doc,CMenu2View.
这5个类是由一个单文档模版关联起来的,彼此是关联的,不是孤立的.

//---

// MainFrm.cpp : implementation of the CMainFrame class
//#include "stdafx.h"
#include "Menu2.h"#include "MainFrm.h"#include "Menu2Doc.h" //这里包含,必须先于Menu2View.h
#include "Menu2View.h"#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif/
// CMainFrameIMPLEMENT_DYNCREATE(CMainFrame, CFrameWnd)BEGIN_MESSAGE_MAP(CMainFrame, CFrameWnd)//{
   {AFX_MSG_MAP(CMainFrame)// NOTE - the ClassWizard will add and remove mapping macros here.//    DO NOT EDIT what you see in these blocks of generated code !ON_WM_CREATE()//}}AFX_MSG_MAP
END_MESSAGE_MAP()static UINT indicators[] =
{ID_SEPARATOR,           // status line indicatorID_INDICATOR_CAPS,ID_INDICATOR_NUM,ID_INDICATOR_SCRL,
};/
// CMainFrame construction/destructionCMainFrame::CMainFrame()
{// TODO: add member initialization code here}CMainFrame::~CMainFrame()
{
}int CMainFrame::OnCreate(LPCREATESTRUCT lpCreateStruct)
{if (CFrameWnd::OnCreate(lpCreateStruct) == -1)return -1;if (!m_wndToolBar.CreateEx(this, TBSTYLE_FLAT, WS_CHILD | WS_VISIBLE | CBRS_TOP| CBRS_GRIPPER | CBRS_TOOLTIPS | CBRS_FLYBY | CBRS_SIZE_DYNAMIC) ||!m_wndToolBar.LoadToolBar(IDR_MAINFRAME)){TRACE0("Failed to create toolbar\n");return -1;      // fail to create}if (!m_wndStatusBar.Create(this) ||!m_wndStatusBar.SetIndicators(indicators,sizeof(indicators)/sizeof(UINT))){TRACE0("Failed to create status bar\n");return -1;      // fail to create}// TODO: Delete these three lines if you don't want the toolbar to//  be dockablem_wndToolBar.EnableDocking(CBRS_ALIGN_ANY);EnableDocking(CBRS_ALIGN_ANY);DockControlBar(&m_wndToolBar);return 0;
}BOOL CMainFrame::PreCreateWindow(CREATESTRUCT& cs)
{if( !CFrameWnd::PreCreateWindow(cs) )return FALSE;// TODO: Modify the Window class or styles here by modifying//  the CREATESTRUCT csreturn TRUE;
}/
// CMainFrame diagnostics#ifdef _DEBUG
void CMainFrame::AssertValid() const
{CFrameWnd::AssertValid();
}void CMainFrame::Dump(CDumpContext& dc) const
{CFrameWnd::Dump(dc);
}#endif //_DEBUG/
// CMainFrame message handlersBOOL CMainFrame::OnCommand(WPARAM wParam, LPARAM lParam) 
{/* 可以这样,还是回到让view类去处理.....return CFrameWnd::OnCommand(wParam, lParam); //调用基类的命令:会出现COMMAND消息路由,会让view去响应.*/// TODO: Add your specialized code here and/or call the base classint MenuCmdID = LOWORD(wParam);//CMenu2View view; 这么搞是不行的,因为:/*虽然view的确是一个CMenu2View的对象,照这么定义的话,CMenu2View X1,X2,X3,X4; 这些X1,X2,X3,X4也都是CMenu2View的对象但是这些对象都不是那个与本应用程序的框架类关联了的CMenu2View对象首先,这个程序是由MFC向导生成的单文档应用程序,生成的5个类CAboutDlg,CMainFrame,CMenu2App,CMenu2Doc,CMenu2View是有一个单文档关联起来了,彼此是关联的.*/CMenu2View *pView = (CMenu2View*)GetActiveView(); //GetActiveView()返回附加在框架上的active view的指针	if(MenuCmdID>=IDM_PHONE1&&MenuCmdID<IDM_PHONE1+pView->m_strArray.GetSize()){CClientDC dc(pView); //这里不能用this,因为在CMainFrame类中用this指向的是CMainFrame;而我们要操作的是视类.	dc.TextOut(0,0,pView->m_strArray.GetAt(MenuCmdID-IDM_PHONE1));MessageBox("CMainFrame::OnCommand");return true; //跳出来,不再让基类派生的view去响应}return CFrameWnd::OnCommand(wParam, lParam); //调用基类的命令:会出现COMMAND消息路由,会让view去响应.
}