三、程序代码
////////////////////////////////
#ifndef __TRANSPARENTIMAGE_H_TRANSPARENTIMAGE_42A6E395_97E4_11D3_B6F0_005004024A9E
#define __TRANSPARENTIMAGE_H_TRANSPARENTIMAGE_42A6E395_97E4_11D3_B6F0_005004024A9E
#if _MSC_VER ＞= 1000
#pragma once
#endif
class CTransparentImage : public CStatic
{
public:
CTransparentImage() ;
virtual ~CTransparentImage() ;
protected:
//{{AFX_MSG( CTransparentImage )
afx_msg void OnPaint() ;
//}}AFX_MSG
DECLARE_MESSAGE_MAP()
} ;
//{{AFX_INSERT_LOCATION}}
#endif
////////////////////////////////////
#include "StdAfx.h"
#include "TransparentImage.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__ ;
#endif
CTransparentImage::CTransparentImage()
{}
CTransparentImage::~CTransparentImage()
{}
BEGIN_MESSAGE_MAP( CTransparentImage, CStatic )
//{{AFX_MSG_MAP( CTransparentImage )
ON_WM_PAINT()
//}}AFX_MSG_MAP
END_MESSAGE_MAP()
void CTransparentImage::OnPaint()
{
HBITMAP l_hbmpBitmap = GetBitmap() ;
if( l_hbmpBitmap == NULL )
{
Default() ;
return ;
}
CPaintDC l_PaintDC( this ) ;
// Prepare everything for drawing
CRect l_rcClient ;
GetClientRect( &l_rcClient ) ;
CDC l_BufferDC ;
l_BufferDC.CreateCompatibleDC( &l_PaintDC ) ;
CBitmap l_BufferBitmap ;
l_BufferBitmap.CreateCompatibleBitmap(&l_PaintDC,l_rcClient.Width(), l_rcClient.Height() ) ;
CBitmap* l_pOldBufferBitmap = l_BufferDC.SelectObject( &l_BufferBitmap ) ;
CDC l_MaskDC ;
l_MaskDC.CreateCompatibleDC( &l_PaintDC ) ;
CBitmap l_MaskBitmap ;
l_MaskBitmap.CreateBitmap( l_rcClient.Width(), l_rcClient.Height(), 1, 1, NULL ) ;
CBitmap* l_pOldMaskBitmap = l_MaskDC.SelectObject( &l_MaskBitmap ) ;
#define SRCMASK 0x00220326
// Fill with transparent color
l_BufferDC.FillSolidRect( &l_rcClient, RGB( 255, 0, 255 ) ) ;
// Blit the bitmap to the buffer
CDC l_MemoryDC ;
l_MemoryDC.CreateCompatibleDC( &l_PaintDC ) ;
CBitmap* l_pOldMemoryBitmap = l_MemoryDC.SelectObject( CBitmap::FromHandle( l_hbmpBitmap ) ) ;
l_BufferDC.BitBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(), &l_MemoryDC,0, 0, SRCCOPY ) ;
l_MemoryDC.SelectObject( l_pOldMemoryBitmap ) ;
// Create the mask.
COLORREF l_crOldBack = l_BufferDC.SetBkColor( RGB( 255, 0, 255 ) ) ;
l_MaskDC.BitBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(), &l_BufferDC,0, 0, SRCCOPY ) ;
l_BufferDC.SetBkColor( l_crOldBack ) ;
// Draw the bitmap transparently now；
if( ! l_PaintDC.MaskBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(),&l_BufferDC, 0, 0, l_MaskBitmap, 0, 0,ROP4_TRANSPARENTBLIT ) )
{
CDC l_CopyDC ;
l_CopyDC.CreateCompatibleDC( &l_PaintDC ) ;
CBitmap l_CopyBitmap ;
l_CopyBitmap.CreateCompatibleBitmap( &l_PaintDC, l_rcClient.Width(),l_rcClient.Height() ) ;
CBitmap* l_pOldCopyBitmap = l_CopyDC.SelectObject( &l_CopyBitmap ) ;
l_CopyDC.BitBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(), &l_PaintDC,0, 0, SRCCOPY ) ;
l_CopyDC.BitBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(), &l_MaskDC,0, 0, SRCAND ) ;
l_BufferDC.BitBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(), &l_MaskDC,0, 0, SRCINVERT ) ;
l_CopyDC.BitBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(), &l_BufferDC,0, 0, SRCPAINT ) ;
l_PaintDC.BitBlt( 0, 0, l_rcClient.Width(), l_rcClient.Height(), &l_CopyDC,0, 0, SRCCOPY ) ;
l_CopyDC.SelectObject( l_pOldCopyBitmap ) ;
}
// Clean up.
l_MaskDC.SelectObject( l_pOldMaskBitmap ) ;
l_BufferDC.SelectObject( l_pOldBufferBitmap ) ;
}
四、小结
本实例介绍了如何在对话框中实现透明位图的显示，读者朋友可能感觉到文中介绍的方法和代码的实现过程仿佛不太一致，其实这些只是表面现象，读者朋友在吃透实例代码的实现过程后，就会发现两者之间并没有什么冲突。
