button.cpp

如何在对话框中实现3D文本效果

//
// MyTextButton.h interface for CMyTextButton
// (c) Roger Onslow, 1997
// use freely and enjoy
///////////////////////////////////////////////////////////////////////////
//

#ifndef _CMyTextButton_
#define _CMyTextButton_

///////////////////////////////////////////////////////////////////////////
//
// CMyTextButton control

class CMyTextButton : public CButton {
     bool m_bUse3D;
public:
     CMyTextButton() : m_bUse3D(true) {}
     void Use3D(bool bUse3D=true) { m_bUse3D = bUse3D; }
protected:
     void Draw(CDC* pDC, const CRect& rect, UINT state);
     //{{AFX_MSG(CMyTextButton)
     afx_msg void DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct);
     afx_msg BOOL OnEraseBkgnd(CDC* pDC);
     //}}AFX_MSG
     //{{AFX_VIRTUAL(CMyTextButton)
     virtual void PreSubclassWindow();
     //}}AFX_VIRTUAL
     DECLARE_MESSAGE_MAP()
};

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

#endif



///////////////////////////////////////////////////////////////////////////
//
// MyTextButton.cpp - large text which acts as a button
// (c) Roger Onslow, 1997
// use freely and enjoy
///////////////////////////////////////////////////////////////////////////
//
#include "stdafx.h"
#include "MyTextButton.h"

#ifdef _DEBUG
#undef THIS_FILE
static char BASED_CODE THIS_FILE[] = __FILE__;
#endif

///////////////////////////////////////////////////////////////////////////
//
// CMyTextButton

BEGIN_MESSAGE_MAP(CMyTextButton, CButton)
     //{{AFX_MSG_MAP(CMyTextButton)
     ON_WM_DRAWITEM()
     ON_WM_ERASEBKGND()
     //}}AFX_MSG_MAP
END_MESSAGE_MAP()

void CMyTextButton::PreSubclassWindow() {
     SetButtonStyle(GetButtonStyle() | BS_OWNERDRAW);
}

///////////////////////////////////////////////////////////////////////////
//
// CMyTextButton message handlers

void CMyTextButton::DrawItem(LPDRAWITEMSTRUCT lpDrawItemStruct) {
     CDC* pDC = CDC::FromHandle(lpDrawItemStruct->hDC);
     ASSERT_VALID(pDC);
     CRect rectClient = lpDrawItemStruct->rcItem;
     Draw(pDC,rectClient, lpDrawItemStruct->itemState);
}

void CMyTextButton::Draw(CDC* pDC, const CRect& rect, UINT state) {
     CString text; GetWindowText(text);
     int l = text.GetLength();
     CRect rectClient = rect;

     // get font from control
     CFont* pFont = GetFont();

     // ensure we have a valid height and width and select the font
     LOGFONT logfont;
     pFont->GetObject(sizeof(LOGFONT),&logfont);
     if (logfont.lfHeight == 0) logfont.lfHeight = 20;
     logfont.lfWidth = 0;     // 0 so it will be calculated
     logfont.lfWeight = 1000;
     logfont.lfEscapement = logfont.lfOrientation = 0;
     CFont tryfont; VERIFY(tryfont.CreateFontIndirect(&logfont));
     CFont* pFontOld = pDC->SelectObject(&tryfont);

     // get the control size and adjust font width & height accordingly
     if (m_bUse3D) rectClient.DeflateRect(3,3);
     CSize textSizeClient = pDC->GetTextExtent(text,l);
     if (rectClient.Width()*textSizeClient.cy >
rectClient.Height()*textSizeClient.cx) {
          logfont.lfHeight = ::MulDiv(logfont.
lfHeight,rectClient.Height(),textSizeClient.cy);
     } else {
          logfont.lfHeight = ::MulDiv(logfont.
lfHeight,rectClient.Width(),textSizeClient.cx);
     }
     logfont.lfHeight--; // fudge factor
     if (m_bUse3D) rectClient.InflateRect(3,3);

     // create adjusted font and select
     CFont font; font.CreateFontIndirect(&logfont);
     pDC->SelectObject(&font);
     textSizeClient = pDC->GetTextExtent(text,l);

     int minx = rectClient.left+(rectClient.Width()-textSizeClient.cx)/2;
     int miny = rectClient.top+(rectClient.Height()-textSizeClient.cy)/2;

     int oldBkMode = pDC->SetBkMode(TRANSPARENT);
     COLORREF textcol = ::GetSysColor((state & ODS_FOCUS) ? COLOR_GRAYTEXT
: COLOR_BTNTEXT);
     COLORREF oldTextColor = pDC->SetTextColor(textcol);

     int cx = minx;
     int cy = miny;
     if (m_bUse3D) {
          int s = (state & ODS_SELECTED) ? -1 : +1;
          cx += 3; cy += 3;

          // draw 3D highlights
          pDC->SetTextColor(::GetSysColor(COLOR_3DDKSHADOW));
          pDC->TextOut(cx-s*2,cy+s*2,text);
          pDC->TextOut(cx+s*2,cy-s*2,text);
          pDC->TextOut(cx+s*2,cy+s*2,text);
          pDC->SetTextColor(::GetSysColor(COLOR_3DHILIGHT));
          pDC->TextOut(cx+s*1,cy-s*2,text);
          pDC->TextOut(cx-s*2,cy+s*1,text);
          pDC->TextOut(cx-s*2,cy-s*2,text);
          pDC->SetTextColor(::GetSysColor(COLOR_3DSHADOW));
          pDC->TextOut(cx-s*1,cy+s*1,text);
          pDC->TextOut(cx+s*1,cy-s*1,text);
          pDC->TextOut(cx+s*1,cy+s*1,text);
          pDC->SetTextColor(::GetSysColor(COLOR_3DLIGHT));
          pDC->TextOut(cx,cy-s*1,text);
          pDC->TextOut(cx-s*1,cy,text);
          pDC->TextOut(cx-s*1,cy-s*1,text);
          pDC->SetTextColor(textcol);
     }
     // draw the text
     pDC->TextOut(cx,cy,text);

     // restore DC
     pDC->SetTextColor(oldTextColor);
     pDC->SetBkMode(oldBkMode);
     pDC->SelectObject(pFontOld);
}

BOOL CMyTextButton::OnEraseBkgnd(CDC*) {
     return true;    // we don't do any erasing...
}