VC++的菜单控制和自绘菜单

菜单控制
为什么即使调用EnableMenuItem菜单项后，菜单项还处于禁止状态  

需要将CFrameWnd:: m_bAutomenuEnable设置为FALSE，如果该数据成员为TRUE（缺省值），工作框将自动地禁止没有ON_UPDATE_COMMAND_UI或者ON_COMMAND的菜单项。

//Disable MFC from automatically disabling menu items.

m_bAuoMenuEnable=FALSE;

//Now enable the menu item.

CMenu* pMenu=GetMenu ();

ASSERT_VALID (pMenu);

pMenu->EnableMenuItem (ID_MENU_ITEM,MF_BYCOMMAND | MF_ENABLED);



如何给系统菜单添加一个菜单项  

给系统菜单添加一个菜单项需要进行下述三个步骤：

首先，使用Resource Symbols对话（在View菜单中选择Resource Symbols．．．

可以显示该对话）定义菜单项ID，该ID应大于0x0F而小于0xF000；

其次，调用CWnd::GetSystemMenu获取系统菜单的指针并调用CWnd:: Appendmenu将菜单项添加到菜单中。下例给系统菜单添加两个新的菜单项：

int CMainFrame:: OnCreate (LPCREATESTRUCT lpCreateStruct)

{

…

//Make sure system menu item is in the right range.

ASSERT (IDM_MYSYSITEM &0xFFF0)==IDM_MYSYSITEM);

ASSERT (IDM-MYSYSITEM<0xF000);

//Get pointer to system menu.

CMenu* pSysmenu=GetSystemmenu (FALSE);

ASSERT_VALID (pSysMenu);

//Add a separator and our menu item to system menu.

CString StrMenuItem (_T ("New menu item"));

pSysMenu->Appendmenu (MF_SEPARATOR);

pSysMenu->AppendMenu (MF_STRING, IDM_MYSYSITEM, strMenuitem);

…

}

现在，选择系统菜单项时用户应进行检测。使用ClassWizard处理

WM_SYSCOMMAND消息并检测用户菜单的nID参数：

void CMainFrame:: OnSysCommand (UINT nID,LPARAM lParam)

{

//Determine if our system menu item was selected.

if ( (nID & 0xFFF0)==IDM_MYSYSITEM)

{

//TODO-process system menu item

}

else

CMDIFrameWnd:: OnSysCommand (nID, lParam);

}

最后，一个设计良好的UI应用程序应当在系统菜单项加亮时在状态条显示一个帮助信息，这可以通过增加一个包含系统菜单基ID的串表的入口来实现。



如何确定顶层菜单所占据的菜单行数  

这可以通过简单的减法和除法来实现。首先，用户需要计算主框窗口的高度和客户区；其次，从主框窗口的高度中减去客户区、框边界以及标题的高度；最后，除以菜单栏的高度。下例成员函数是一个计算主框菜单所占据的行数的代码实现。

int CMainFrame:: GetMenuRows ()

{

CRect rcFrame,rcClient;

GetWindowRect (rcFrame);

GetClientRect (rcClient);

return (rcFrame.Height () -rcClient.Height ()-

:: GetSystemMetrics (SM_CYCAPTION) -

(:: getSystemMetrics (SM_CYFRAME) *2)) /

:: GetSystemMetrics (SM_CYMENU);

}




自绘菜单
闻怡洋译 

在这里提供一个C++类(CCustomMenu)，该类是CMenu的子类，并且拥有自绘能力。它可以向你提供以下的功能：

设置字体颜色。
设置高亮度颜色。
设置高亮度时的风格。
设置选中时和在普通状态下的菜单显示的图标。
设置显示图标大小。
在CCustomMenu中定义了结构MENUDATA，你必须根据你的需要填充该结构，并且在增加菜单时提供该结构的指针(调用AppendMenu,InsertMenu)。下面是一个例子：

1、定义CCustomMenu的实例，和MENUDATA结构变量。

    CCustomMenu m_cCustomMenu;
    MENUDATA menuData [8]; // as many menu items are present , You should be able to use
                //new and do the same
2、调用CreateMenu()设置有关参数。
    m_customMenu.CreateMenu ();
    m_customMenu.SetIconSize (25,25); //This is to set the size of the Icon.
                        // This should be used only once for any menu
    // in order to resize it, destroy and create the menu again with different size.
    m_customMenu.SetHighlightStyle (Normal); //Or TextOnly, if you want the
    // background color to remain the same
    // and the Text color to change to the Highlight color.
        // The following setXXXColor sets the menu colors. If you dont want to change any, Dont call these member functions.
     m_customMenu.SetTextColor (RGB (255,0,0));
     m_customMenu.SetBackColor (RGB (255,255,255));
     m_customMenu.SetHighlightColor (RGB (0,0,255));
3、设置MENUDATA变量，并增加菜单项。
     lstrcpy (menuData[0].menuText , "text1");
     menuData[0].menuIconNormal= IDI_ICON1;
     m_customMenu.AppendMenu (MF_OWNERDRAW,3,(LPCTSTR)menuData);

3、在你的窗口中重载OnMeasureItem(...)函数。
void CMyView::OnMeasureItem(int nIDCtl, LPMEASUREITEMSTRUCT lpMeasureItemStruct)
{
    if ( lpMeasureItemStruct->CtlType == ODT_MENU &&
            IsMenu((HMENU)lpMeasureItemStruct->itemID) &&
            (lpMeasureItemStruct->itemID == (UINT)m_hMenuSub) )
    {
        m_customMenu.MeasureItem (lpMeasureItemStruct);
    }
    else
        // let MFC's self-drawing handle it
        CView::OnMeasureItem(nIDCtl, lpMeasureItemStruct);
}

下面的函数将帮助你设置菜单属性。

    void SetTextColor (COLORREF );
    void SetBackColor (COLORREF);
    void SetHighlightColor (COLORREF);
    void SetIconSize (int, int);
    void SetHighlightStyle (HIGHLIGHTSTYLE ); // HIGHLIGHTSTYLE : enum {Normal, TextOnly}
    void SetHighlightTextColor (COLORREF);



下面是文件代码：
//*************************************************************************
// CustomMenu.h : header file
//

#if
!defined(AFX_CUSTOMMENU_H__FE5B01C3_1E02_11D1_B87A_0060979CDF6D__INCLUDED_)
#define AFX_CUSTOMMENU_H__FE5B01C3_1E02_11D1_B87A_0060979CDF6D__INCLUDED_

#if _MSC_VER >= 1000
#pragma once
#endif // _MSC_VER >= 1000
class MENUDATA
{
public:
    MENUDATA () { menuIconNormal = -1; menuIconSelected = -1;};
    char menuText[32];
    UINT menuIconNormal;
    UINT menuIconSelected;
};

typedef enum {Normal,TextOnly} HIGHLIGHTSTYLE;

////////////////////////////////////////////////
//
// CCustomMenu window

class CCustomMenu : public CMenu
{
// Construction
public:
    CCustomMenu();

// Attributes
public:

// Operations
public:

// Overrides
    // ClassWizard generated virtual function overrides
    //{{AFX_VIRTUAL(CCustomMenu)
    //}}AFX_VIRTUAL

// Implementation
public:
    virtual ~CCustomMenu();
    virtual void DrawItem( LPDRAWITEMSTRUCT);
    virtual void MeasureItem( LPMEASUREITEMSTRUCT );
    void SetTextColor (COLORREF );
    void SetBackColor (COLORREF);
    void SetHighlightColor (COLORREF);
    void SetIconSize (int, int);
    void SetHighlightStyle (HIGHLIGHTSTYLE );
    void SetHighlightTextColor (COLORREF);

    // Generated message map functions
protected:
    COLORREF m_crText;
    COLORREF m_clrBack;
    COLORREF m_clrText;
    COLORREF m_clrHilight;
    COLORREF m_clrHilightText;
    LOGFONT m_lf;
    CFont m_fontMenu;
    UINT m_iMenuHeight;
    BOOL m_bLBtnDown;
    CBrush m_brBackground,m_brSelect;
    CPen m_penBack;
    int m_iconX,m_iconY;
    HIGHLIGHTSTYLE m_hilightStyle;

    //{{AFX_MSG(CCustomMenu)
        // NOTE - the ClassWizard will add and remove member functions here.
    //}}AFX_MSG
};

///////////////////////////////////////
//

//{{AFX_INSERT_LOCATION}}
// Microsoft Developer Studio will insert additional declarations immediately before the previous line.

#endif //!defined(AFX_CUSTOMMENU_H__FE5B01C3_1E02_11D1_B87A_0060979CDF6D__INCLUDED_)

//*************************************************************************
// CustomMenu.cpp : implementation file
//

#include "stdafx.h"
#include "CustomMenu.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

////////////////////////////////////////////////
//
// CCustomMenu

CCustomMenu::CCustomMenu()
{
    m_clrText = GetSysColor (COLOR_MENUTEXT);
    m_clrBack = GetSysColor (COLOR_MENU);
    m_brBackground.CreateSolidBrush (m_clrBack);
    m_penBack.CreatePen (PS_SOLID,0,m_clrBack);
    m_crText = m_clrText;
    m_bLBtnDown = FALSE;
    m_iconX = GetSystemMetrics ( SM_CXMENUCHECK);
    m_iconY = GetSystemMetrics (SM_CYMENUCHECK );

    m_clrHilight = GetSysColor (COLOR_HIGHLIGHT);
    m_brSelect.CreateSolidBrush (m_clrHilight);
    m_clrHilightText = GetSysColor (COLOR_HIGHLIGHTTEXT);

    ZeroMemory ((PVOID) &m_lf,sizeof (LOGFONT));
    NONCLIENTMETRICS nm;
    nm.cbSize = sizeof (NONCLIENTMETRICS);

    //Get the system metrics for the Captionfromhere
    VERIFY (SystemParametersInfo (SPI_GETNONCLIENTMETRICS,0,&nm,0));

    m_lf = nm.lfMenuFont;
    m_iMenuHeight = nm.iMenuHeight;
    m_fontMenu.CreateFontIndirect (&m_lf);
}

CCustomMenu::~CCustomMenu()
{
    if ((HBRUSH) m_brBackground != NULL)
        m_brBackground.DeleteObject ();
    if ((HFONT)m_fontMenu !=NULL)
        m_fontMenu.DeleteObject ();
    if ((HBRUSH)m_brSelect != NULL)
         m_brSelect.DeleteObject ();
}



////////////////////////////////////////////////
//
// CCustomMenu message handlers


void CCustomMenu::DrawItem (LPDRAWITEMSTRUCT lpDIS)
{
    ASSERT(lpDIS != NULL);

    CDC* pDC = CDC::FromHandle(lpDIS->hDC);
    CRect rect;
    HICON hIcon;
    COLORREF crText = m_crText;
    // draw the colored rectangle portion
    rect.CopyRect(&lpDIS->rcItem);

    // draw the up/down/focused/disabled state

    UINT action = lpDIS->itemAction;
    UINT state = lpDIS->itemState;
    CString strText;
    LOGFONT lf;
    lf = m_lf;

    CFont dispFont;
    CFont *pFont;
    //GetWindowText(strText);
    if (lpDIS->itemData != NULL)
    {
        strText = (((MENUDATA*) (lpDIS->itemData))->menuText);
        if ((((MENUDATA *)(lpDIS->itemData))->menuIconNormal) == -1)
            hIcon = NULL;
        else if (state & ODS_SELECTED)
        {
            if ((((MENUDATA *)(lpDIS->itemData))->menuIconSelected) != -1)
                hIcon = AfxGetApp ()->LoadIcon (((MENUDATA *)(lpDIS->itemData))->menuIconSelected);
            else
                hIcon = AfxGetApp()->LoadIcon (((MENUDATA*)(lpDIS->itemData))->menuIconNormal);
        }
        else
            hIcon = AfxGetApp()->LoadIcon (((MENUDATA*)(lpDIS->itemData))->menuIconNormal);

        TRACE1 ("Draw for %s ", strText);
    }
    else
    {
        strText.Empty();
        hIcon = NULL;
    }

    if ( (state & ODS_SELECTED) )
    {
        // draw the down edges

        CPen *pOldPen = pDC->SelectObject (&m_penBack);

        //You need only Text highlight and thats what you get
        if (m_hilightStyle != Normal)
        {
            pDC->FillRect (rect,&m_brBackground);
        }
        else
        {
            pDC->FillRect (rect,&m_brSelect);
        }

        pDC->SelectObject (pOldPen);
        pDC->Draw3dRect (rect,GetSysColor (COLOR_3DHILIGHT),GetSysColor(COLOR_3DSHADOW));
        lf.lfWeight = FW_BOLD;
        if ((HFONT)dispFont != NULL)
            dispFont.DeleteObject ();
        dispFont.CreateFontIndirect (&lf);
        crText = m_clrHilightText;

        //While selected move the text a bit
        TRACE0 ("SELECT,SELECTED ");
    }
    else
    {
        CPen *pOldPen = pDC->SelectObject (&m_penBack);
        pDC->FillRect (rect,&m_brBackground);
        pDC->SelectObject (pOldPen);
        // draw the up edges
        pDC->Draw3dRect (rect,m_clrBack,m_clrBack);
        if ((HFONT)dispFont != NULL)
            dispFont.DeleteObject ();
        dispFont.CreateFontIndirect (&lf); //Normal

        TRACE0 ("SELECT, NORMAL ");
    }

    // draw the text if there is any
    //We have to paint the text only if the image is nonexistant
    if (hIcon != NULL)
    {
        if(DrawIconEx (pDC->GetSafeHdc(),rect.left,rect.top,hIcon,
            (m_iconX)?m_iconX:32,(m_iconY)?m_iconY:32,0,NULL,DI_NORMAL))
            TRACE0("Wrote the icon successfully ");
        else
            TRACE0 ("SORRY.NOGO ");
    }
    //This is needed always so that we can have the space for check marks
    rect.left = rect.left +((m_iconX)?m_iconX:32);

    if ( !strText.IsEmpty())
    {
        // pFont->GetLogFont (&lf);

        int iOldMode = pDC->GetBkMode();

        pDC->SetBkMode( TRANSPARENT);

        pDC->SetTextColor( crText);

        pFont = pDC->SelectObject (&dispFont);
        TRACE1( "About To DrawText %s ",strText);
        pDC->DrawText (strText,rect,DT_LEFT|DT_SINGLELINE|DT_VCENTER);
        TRACE0("Done ");
        pDC->SetBkMode( iOldMode );
        pDC->SelectObject (pFont); //set it to the old font
    }
    dispFont.DeleteObject ();
}

void CCustomMenu::MeasureItem( LPMEASUREITEMSTRUCT lpMIS )
{
    CDC *pDC = AfxGetApp()->m_pMainWnd->GetDC();
    CFont* pFont = pDC->SelectObject (&m_fontMenu);
    int iconX = 0,iconY= 0;
    TEXTMETRIC tm;
    pDC->GetTextMetrics (&tm);
    pDC->SelectObject (pFont);
    AfxGetApp()->m_pMainWnd->ReleaseDC (pDC);

    if (m_iconX)
        iconX = m_iconX;
    if (m_iconY)
        iconY = m_iconY;

    lpMIS->itemWidth = iconX + tm.tmAveCharWidth * lstrlen(((MENUDATA*)(lpMIS->itemData))->menuText) +10;
    lpMIS->itemHeight = (iconY > (m_iMenuHeight+1))?iconY:m_iMenuHeight + 1;
}

void CCustomMenu::SetIconSize (int width, int height)
{
    m_iconX = width;
    m_iconY = height;
}

void CCustomMenu::SetTextColor (COLORREF clrText)
{
    m_crText = clrText;
}

void CCustomMenu::SetBackColor (COLORREF clrBack)
{
    m_clrBack = clrBack;
    if ((HBRUSH)m_brBackground != NULL)
        m_brBackground.DeleteObject ();
    m_brBackground.CreateSolidBrush (clrBack);
}

void CCustomMenu::SetHighlightColor (COLORREF clrHilight)
{
    m_clrHilight = clrHilight;
    if ((HBRUSH)m_brSelect != NULL)
            m_brSelect.DeleteObject ();
    m_brSelect.CreateSolidBrush (clrHilight);
}

void CCustomMenu::SetHighlightTextColor (COLORREF clrHilightText)
{
    m_clrHilightText = clrHilightText;
}


void CCustomMenu::SetHighlightStyle (HIGHLIGHTSTYLE hilightStyle)
{
    m_hilightStyle = hilightStyle;
}