三态位图按钮

下午无聊写的一个简单三态按钮，功能很有限，对于一般的不需要拉伸的对话框还比较适用(不能指定WS_CLIPCHILDREN风格):

class CBitmapButton : public CWindowImpl<CBitmapButton,CButton>, public COwnerDraw<CBitmapButton>{private:bool m_bTracking;bool m_bDCStored;CBitmap m_bitmapNor;CBitmap m_bitmapOver;CBitmap m_bitmapDown;public:CBitmapButton():m_bTracking(false),m_bDCStored(false){}virtual ~CBitmapButton(){}void SetImage(CString strNormal, CString strHover, CString strDown){m_bitmapNor=(HBITMAP)::LoadImage(NULL,strNormal,IMAGE_BITMAP,0,0,LR_LOADFROMFILE);m_bitmapOver=(HBITMAP)::LoadImage(NULL,strHover,IMAGE_BITMAP,0,0,LR_LOADFROMFILE);m_bitmapDown=(HBITMAP)::LoadImage(NULL,strDown,IMAGE_BITMAP,0,0,LR_LOADFROMFILE);}void SetImage(UINT nNormalID, UINT nHoverID, UINT nDownID){m_bitmapNor.LoadBitmap(nNormalID);m_bitmapOver.LoadBitmap(nHoverID);m_bitmapDown.LoadBitmap(nDownID);}BEGIN_MSG_MAP(CBitmapButton)MESSAGE_HANDLER(WM_CREATE,OnCreate)MESSAGE_HANDLER(WM_ERASEBKGND,OnEraseBkgnd)MESSAGE_HANDLER(WM_MOUSEMOVE,OnMouseMove)MESSAGE_HANDLER(WM_MOUSELEAVE,OnMouseLeave)CHAIN_MSG_MAP_ALT(COwnerDraw<CBitmapButton>,1)DEFAULT_REFLECTION_HANDLER()END_MSG_MAP()LRESULT OnCreate(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& bHandled){Init();bHandled = FALSE;return 1;}LRESULT OnEraseBkgnd(UINT /*uMsg*/, WPARAM wParam, LPARAM /*lParam*/, BOOL& bHandled){return 1;}LRESULT OnMouseMove(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& bHandled){bHandled=FALSE;if (!m_bTracking){TRACKMOUSEEVENT tme;tme.cbSize = sizeof (tme);tme.hwndTrack = m_hWnd;tme.dwFlags = TME_LEAVE;tme.dwHoverTime = 1;m_bTracking = _TrackMouseEvent(&tme);Invalidate(FALSE);}return 0;}LRESULT OnMouseLeave(UINT /*uMsg*/, WPARAM /*wParam*/, LPARAM /*lParam*/, BOOL& bHandled){bHandled=false;m_bTracking = false;Invalidate(FALSE);return 0;}void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct) {CDCHandle dc = lpDrawItemStruct->hDC;CRect rcBtn( lpDrawItemStruct->rcItem);BITMAP bmpInfo;m_bitmapNor.GetBitmap(&bmpInfo);if (m_bTracking){CDC dctemp;dctemp.CreateCompatibleDC(dc);dctemp.SelectBitmap(m_bitmapOver);::TransparentBlt(dc,0,0, lpDrawItemStruct->rcItem.right, lpDrawItemStruct->rcItem.bottom, dctemp.m_hDC, 0,0, bmpInfo.bmWidth, bmpInfo.bmHeight, RGB(255,0,255));}if (lpDrawItemStruct->itemState & ODS_SELECTED){CDC dctemp;dctemp.CreateCompatibleDC(dc);dctemp.SelectBitmap(m_bitmapDown);::TransparentBlt(dc,0,0, lpDrawItemStruct->rcItem.right, lpDrawItemStruct->rcItem.bottom, dctemp.m_hDC, 0,0, bmpInfo.bmWidth, bmpInfo.bmHeight, RGB(255,0,255));}else if (!m_bTracking){CDC dctemp;dctemp.CreateCompatibleDC(dc);dctemp.SelectBitmap(m_bitmapNor);::TransparentBlt(dc,0,0, lpDrawItemStruct->rcItem.right, lpDrawItemStruct->rcItem.bottom, dctemp.m_hDC, 0,0, bmpInfo.bmWidth, bmpInfo.bmHeight, RGB(255,0,255));}int cchLen=GetWindowTextLength()+1;if (cchLen>1){CFont oldFont=dc.SelectFont(GetFont());LPTSTR strText=NULL;strText=new TCHAR[cchLen];::memset(strText,0,cchLen);GetWindowText(strText,cchLen);CRect rtText;GetClientRect(&rtText);dc.SetBkMode(TRANSPARENT);dc.DrawText(strText,cchLen-1,&rtText, DT_CENTER|DT_SINGLELINE |DT_VCENTER);delete strText;dc.SelectFont(oldFont);}}protected:void Init(){ModifyStyle(0,BS_OWNERDRAW);}};