本程序介绍一种自绘制按钮的实现：当鼠标光标拖过按钮时，文本变成黑体，具有焦点的按钮在文本下加下划线。当点击它时，文本变成黑体。同时该按钮还支持位图。使用SetBitmap (UINT ID) 可以将位图添加到按钮上：如果按钮不具有焦点，位图为单色；当鼠标拖过它时，位图将恢复到它以前的颜色。
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// BtnMenu.cpp : implementation file
//
#include "stdafx.h"
#include "BtnMenu.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
/////////////////////////////////////////////////////////////////////////////
// CBtnMenu
CBtnMenu::CBtnMenu()
{
m_clrText = GetSysColor (COLOR_BTNTEXT);
m_clrBack = GetSysColor (COLOR_BTNFACE);
m_brBackground.CreateSolidBrush (m_clrBack);
m_crText = m_clrText;
m_bLBtnDown = FALSE;
m_idCursor = 0;
m_idBitmap = 0;
}
CBtnMenu::~CBtnMenu()
{
if ((HBRUSH) m_brBackground != NULL)
m_brBackground.DeleteObject ();
}
BEGIN_MESSAGE_MAP(CBtnMenu, CButton)
//{{AFX_MSG_MAP(CBtnMenu)
ON_WM_CTLCOLOR_REFLECT()
ON_WM_MOUSEMOVE()
ON_WM_LBUTTONDOWN()
ON_WM_LBUTTONUP()
ON_WM_TIMER()
//}}AFX_MSG_MAP
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CBtnMenu message handlers
HBRUSH CBtnMenu::CtlColor(CDC* pDC, UINT nCtlColor)
{
// TODO: Change any attributes of the DC here
// TODO: Return a non-NULL brush if the parent's handler should not be called
return NULL;
}
void CBtnMenu::OnMouseMove(UINT nFlags, CPoint point)
{
//Here I will set a timer and see if the current cursor is within our boundaries if
// not kill the timer and remove the current highlighting
SetTimer (1,55,NULL);
CButton::OnMouseMove(nFlags, point);
}
void CBtnMenu::OnLButtonDown(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
m_bLBtnDown= TRUE;
CButton::OnLButtonDown(nFlags, point);
}
void CBtnMenu::OnLButtonUp(UINT nFlags, CPoint point)
{
// TODO: Add your message handler code here and/or call default
m_bLBtnDown= FALSE;
//Take out the cursor
CButton::OnLButtonUp(nFlags, point);
}
void CBtnMenu::DrawItem(LPDRAWITEMSTRUCT lpDIS)
{
ASSERT(lpDIS != NULL);
CDC* pDC = CDC::FromHandle(lpDIS->hDC);
CRect rect;
HBITMAP hBitmap =NULL;
// draw the colored rectangle portion
rect.CopyRect(&lpDIS->rcItem);
// draw the up/down/focused/disabled state
UINT state = lpDIS->itemState;
if ( (state & ODS_SELECTED) )
{
// draw the down edges
CBrush *pOldBrush = pDC->SelectObject(&m_brBackground);
pDC->RoundRect(rect.left, rect.top, rect.Width(), rect.Height(), 2, 2);
pDC->SelectObject(pOldBrush);
if (m_idBitmap)
hBitmap = (HBITMAP) LoadImage (AfxGetInstanceHandle (),MAKEINTRESOURCE (m_idBitmap),
IMAGE_BITMAP,0,0,LR_DEFAULTCOLOR|LR_LOADMAP3DCOLORS|LR_LOADTRANSPARENT);
pDC->Draw3dRect (rect,GetSysColor (COLOR_3DDKSHADOW),GetSysColor (COLOR_3DHILIGHT));
}
else
{
CBrush *pOldBrush = pDC->SelectObject(&m_brBackground);
pDC->RoundRect(rect.left, rect.top, rect.Width(), rect.Height(), 2, 2);
pDC->SelectObject(pOldBrush);
if (m_idBitmap)
hBitmap = (HBITMAP) LoadImage (AfxGetInstanceHandle (),MAKEINTRESOURCE (m_idBitmap),
IMAGE_BITMAP,0,0,LR_MONOCHROME|LR_LOADMAP3DCOLORS);
// draw the up edges
pDC->Draw3dRect (rect,m_clrBack,m_clrBack);
}
// draw the text if there is any
//We have to paint the text only if the image is nonexistant
CString strText;
GetWindowText(strText);
if ( !strText.IsEmpty())
{
LOGFONT lf;
ZeroMemory ((PVOID) &lf,sizeof (LOGFONT));
CFont * pFont = GetFont();
CFont dispFont;
pFont->GetLogFont (&lf);
if ((state & ODS_SELECTED))
{
lf.lfWeight = FW_EXTRABOLD;
dispFont.CreateFontIndirect (&lf);
pFont = pDC->SelectObject (&dispFont);
//While selected move the text a bit
rect.top +=2;
rect.left +=2;
rect.right -=2;
rect.bottom -=2;
}
int iOldMode = pDC->GetBkMode();
COLORREF crOldText = pDC->GetTextColor();
pDC->SetBkMode( TRANSPARENT );
pDC->SetTextColor( m_crText );
if (state & ODS_FOCUS )
{
if (!(state & ODS_SELECTED))
{
lf.lfUnderline = TRUE;
lf.lfWeight = FW_LIGHT;
dispFont.CreateFontIndirect (&lf);
pFont = pDC->SelectObject (&dispFont);
if (m_idBitmap)
hBitmap =(HBITMAP) LoadImage (AfxGetInstanceHandle (),MAKEINTRESOURCE (m_idBitmap),
IMAGE_BITMAP,0,0,LR_DEFAULTCOLOR|LR_LOADMAP3DCOLORS|LR_LOADTRANSPARENT);
}
}
if (state & ODS_DISABLED)
{
CBrush grayBrush;
grayBrush.CreateSolidBrush (GetSysColor (COLOR_GRAYTEXT));
pDC->GrayString (&grayBrush,NULL,(LPARAM)((LPCSTR)strText),-1,rect.left, rect.top,rect.Width(),rect.Height());
}
else
{
if (!hBitmap)
pDC->DrawText(strText, rect, DT_LEFT | DT_VCENTER | DT_SINGLELINE);
else
{
CDC memdc;
CBitmap bmp;
CBitmap *poldbmp;
bmp.Attach (hBitmap);
BITMAP bitmap;
bmp.GetBitmap (&bitmap);
memdc.CreateCompatibleDC( pDC );
// Select the bitmap into the DC
poldbmp = memdc.SelectObject( &bmp);
// Copy (BitBlt) bitmap from memory DC to screen DC
pDC -> StretchBlt( rect.left,rect.top,
rect.right-rect.left, rect.bottom -rect.top, &memdc, 0,0, bitmap.bmWidth,bitmap.bmHeight,SRCCOPY );
memdc.SelectObject( poldbmp );
bmp.Detach ();
}
}
pDC->SetBkMode( iOldMode );
pDC->SetTextColor( crOldText );
pDC->SelectObject (pFont); //set it to the old font
dispFont.DeleteObject ();
}
if ( (state & ODS_DISABLED) )
{
//AST - how should we indicate this???
}
}
void CBtnMenu::OnTimer(UINT nIDEvent)
{
POINT pt;
static BOOL pPainted = FALSE;
GetCursorPos(&pt);
CRect rect;
GetWindowRect (rect);
if (m_bLBtnDown)
{
KillTimer (1);
//Take the cursor out if the man has pressed de button
if (m_idCursor)
{
::SetCursor (AfxGetApp () -> LoadStandardCursor (IDC_ARROW));
}
if (pPainted)
InvalidateRect (NULL);
pPainted = FALSE;
return;
}
if (!rect.PtInRect (pt))
{
KillTimer (1);
//Take out the cursor if the thing is out
if (m_idCursor)
{
::SetCursor (AfxGetApp () -> LoadStandardCursor (IDC_ARROW));
}
if (pPainted)
InvalidateRect (NULL);
pPainted = FALSE;
return;
}
else
{
if (pPainted)
return;
else
pPainted = TRUE;
//Here we need to put the cursor in for the settings
if (m_idCursor)
{
HCURSOR hCursor = AfxGetApp () -> LoadCursor (m_idCursor);
::SetCursor (hCursor);
}
CDC *pDC = GetDC ();
if (!m_idBitmap)
{
LOGFONT lf;
ZeroMemory ((PVOID) &lf,sizeof (LOGFONT));
CFont * pFont = GetFont();
CFont dispFont;
pFont->GetLogFont (&lf);
lf.lfUnderline = TRUE;
lf.lfWeight = FW_BOLD;
int iOldMode = pDC->GetBkMode();
COLORREF crOldText = pDC->GetTextColor();
dispFont.CreateFontIndirect (&lf);
pDC->SetBkMode( TRANSPARENT );
pDC->SetTextColor( m_crText);
pDC -> SelectObject (dispFont);
CString strText;
GetWindowText (strText);
CRect rect;
GetClientRect (rect);
pDC->FillSolidRect (rect,m_clrBack);
pDC->DrawText(strText, rect, DT_LEFT | DT_VCENTER | DT_SINGLELINE);
pDC->SetBkMode( iOldMode );
pDC->SetTextColor( crOldText );
pDC->SelectObject (pFont); //set it to the old font
dispFont.DeleteObject ();
}
else
{
HBITMAP hBitmap =(HBITMAP) LoadImage (AfxGetInstanceHandle (),MAKEINTRESOURCE (m_idBitmap),
IMAGE_BITMAP,0,0,LR_DEFAULTCOLOR|LR_LOADMAP3DCOLORS|LR_LOADTRANSPARENT);
GetClientRect (rect);
CDC memdc;
CBitmap bmp;
CBitmap *poldbmp;
bmp.Attach (hBitmap);
BITMAP bitmap;
bmp.GetBitmap (&bitmap);
memdc.CreateCompatibleDC( pDC );
// Select the bitmap into the DC
poldbmp = (CBitmap *) memdc.SelectObject( &bmp );
// Copy (BitBlt) bitmap from memory DC to screen DC
pDC -> StretchBlt( rect.left,rect.top,
rect.right-rect.left, rect.bottom -rect.top, &memdc, 0,0,bitmap.bmWidth,bitmap.bmHeight, SRCCOPY );
memdc.SelectObject( poldbmp );
}
ReleaseDC (pDC);
}
CButton::OnTimer(nIDEvent);
}
void CBtnMenu::SetBkgndColor (COLORREF rgb)
{
m_clrBack = rgb;
if ((HBRUSH)m_brBackground != NULL)
m_brBackground.DeleteObject();
m_brBackground.CreateSolidBrush (m_clrBack);
}
void CBtnMenu::SetTextColor (COLORREF rgb)
{
m_clrText = rgb;
m_crText = m_clrText;
}
void CBtnMenu::SetCursor(UINT idCursor)
{
m_idCursor = idCursor;
}
void CBtnMenu::SetBitmap (UINT idBmp)
{
m_idBitmap = idBmp;
}
****************************************************************************************
// BtnMenu.h : header file
//
/////////////////////////////////////////////////////////////////////////////
// CBtnMenu window
#ifndef _BTNMENU_H
#define _BTNMENU_H
class CBtnMenu : public CButton
{
// Construction
public:
BOOL m_bLBtnDown;
CBrush m_brBackground;
COLORREF m_crText;
CBtnMenu();
void SetBkgndColor (COLORREF rgb);
void SetTextColor (COLORREF rgb);
void SetBitmap (UINT);
// Attributes
public:
// Operations
public:
// Overrides
// ClassWizard generated virtual function overrides
//{{AFX_VIRTUAL(CBtnMenu)
public:
virtual void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct);
//}}AFX_VIRTUAL
// Implementation
protected:
COLORREF m_clrBack;
COLORREF m_clrText;
UINT m_idBitmap;
public:
UINT m_idCursor;
void SetCursor (UINT idCursor);
virtual ~CBtnMenu();
// Generated message map functions
protected:
//{{AFX_MSG(CBtnMenu)
afx_msg HBRUSH CtlColor(CDC* pDC, UINT nCtlColor);
afx_msg void OnMouseMove(UINT nFlags, CPoint point);
afx_msg void OnLButtonDown(UINT nFlags, CPoint point);
afx_msg void OnLButtonUp(UINT nFlags, CPoint point);
afx_msg void OnTimer(UINT nIDEvent);
//}}AFX_MSG
DECLARE_MESSAGE_MAP()
};
/////////////////////////////////////////////////////////////////////////////
#endif //_BTNMENU_H