MFC CBitmapButton+文字写入

在class view的工程目录下，添加类CImgButton，继承自CBitmapButton。选择CImgButton类的property，重载DrawItem（不是Message下的WM_DRAWITEM，其响应函数OnDrawItem不会被调用到。为什么？），实现在bitmap上写入文字的功能。代码基本照搬http://topic.csdn.net/u/20070611/09/d59ec937-70b1-49f2-b8df-ff44a87b1a04.html里的，附于本文后。使用时，

1）在dialog中拖入一个button，设置ownerdraw。

2）装载需要的位图资源。

3）对话框头文件中 #include "ImgButton.h" CImgButton m_cImgBtn;

4）对话框cpp中 

m_cImgBtn.SubclassDlgItem(IDC_BUTTON5, this);

 m_cImgBtn.LoadBitmaps(IDB_BTNLONGU, IDB_BTNLONGD, IDB_BTNLONGU);

 m_cImgBtn.SizeToContent();  

m_cImgBtn.SetTextColor(RGB(0,0,0));

完成。

CImgButton代码：

#pragma once


// CImgButton

class CImgButton : public CBitmapButton
{
    DECLARE_DYNAMIC(CImgButton)

public:
    CImgButton();
    virtual ~CImgButton();

protected:
    DECLARE_MESSAGE_MAP()
public:

public: 
    COLORREF TextColor; 
    void SetTextColor(COLORREF crColor); 

    virtual void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct);
};




// ImgButton.cpp : implementation file
//

#include "stdafx.h"
#include "win32Test.h"
#include "ImgButton.h"


// CImgButton

IMPLEMENT_DYNAMIC(CImgButton, CBitmapButton)

CImgButton::CImgButton()
{

}

CImgButton::~CImgButton()
{
}


BEGIN_MESSAGE_MAP(CImgButton, CBitmapButton)
END_MESSAGE_MAP()


void CImgButton::SetTextColor(COLORREF crColor) 
{ 
    TextColor = crColor; 
} 

void CImgButton::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct)
{

    // TODO:  Add your code to draw the specified item
    CRect rect = lpDrawItemStruct->rcItem; 
    CDC *pDC = CDC::FromHandle(lpDrawItemStruct->hDC); 
    int nSaveDC = pDC->SaveDC(); 
    UINT state = lpDrawItemStruct->itemState; 
    TCHAR strText[MAX_PATH + 1]; 
    ::GetWindowText(m_hWnd, strText, MAX_PATH); 

    CBitmapButton::DrawItem(lpDrawItemStruct); 

    pDC->SetTextColor(TextColor); 
    if (strText!=NULL) 
    { 
        CFont *hFont = GetFont(); 
        CFont *hOldFont = pDC->SelectObject(hFont); 
        CSize szExtent = pDC->GetTextExtent(strText, lstrlen(strText)); 
        CPoint pt(rect.CenterPoint().x - szExtent.cx / 2, rect.CenterPoint().y - szExtent.cy / 2); 
        if (state & ODS_SELECTED)   
        {
            pt.Offset(1, 1); 
        }
        int nMode = pDC->SetBkMode(TRANSPARENT); 
        if (state & ODS_DISABLED) 
        {
            pDC->DrawState(pt, szExtent, strText, DSS_DISABLED, TRUE, 0, (HBRUSH)NULL); 
        }
        else 
        {
            pDC->DrawState(pt, szExtent, strText, DSS_NORMAL, TRUE, 0, (HBRUSH)NULL); 
        }
        pDC->SelectObject(hOldFont); 
        pDC->SetBkMode(nMode); 
    } 

    pDC->RestoreDC(nSaveDC); 
}