textbar.cpp

这是MFC经典问答书的光盘内容

// TextBar.cpp : implementation file
//

#include "stdafx.h"
#include "CustomBars.h"
#include "TextBar.h"

#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif

/////////////////////////////////////////////////////////////////////////////
// CTextBar

CTextBar::CTextBar()
{
}

CTextBar::~CTextBar()
{
}


BEGIN_MESSAGE_MAP(CTextBar, CControlBar)
	//{{AFX_MSG_MAP(CTextBar)
	ON_WM_CREATE()
	ON_WM_PAINT()
	ON_WM_ERASEBKGND()
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

IMPLEMENT_DYNAMIC(CTextBar, CControlBar)

/////////////////////////////////////////////////////////////////////////////
// CTextBar message handlers

CSize CTextBar::CalcFixedLayout(BOOL bStretch, BOOL bHorz)
{
	CSize size = CControlBar::CalcFixedLayout( bStretch, bHorz );

	// Compute bar width
	CRect rc;
	GetParentFrame()->GetWindowRect( &rc );

	size.cx = rc.Width();	// should be more than wide enough...

	// Compute bar height
	CClientDC dc( this );

	CString strText = _T( "AaBcCcXxYyZz" );	// dummy string to compute text height

	CFont* pOldFont = dc.SelectObject( &m_Font );
	size.cy = dc.GetTextExtent( strText ).cy + TOP_MARGIN * 2;

	dc.SelectObject( pOldFont );

	return size;
}

BOOL CTextBar::Create( CWnd* pParentWnd, DWORD dwStyle, UINT nID )
{
	ASSERT_VALID(pParentWnd);   // must have a parent

	// Style must contain CBRS_TOP or CBRS_BOTTOM
	ASSERT( (dwStyle & CBRS_TOP) || (dwStyle & CBRS_BOTTOM) );

	// 1 - Save the style
	dwStyle |= WS_CHILD | WS_VISIBLE | CBRS_SIZE_FIXED;
	m_dwStyle = dwStyle;

	dwStyle &= ~CBRS_ALL;
	dwStyle |= CCS_NOPARENTALIGN|CCS_NOMOVEY|CCS_NODIVIDER|CCS_NORESIZE;

	// 2 - Create the window
	CRect rc;
	rc.SetRectEmpty();
	if( !CWnd::Create( NULL, NULL, dwStyle, rc, pParentWnd, nID ) )
	{
		return FALSE;
		TRACE0( "Unable to create text bar window\n" );
	}
	
	return TRUE;
}

int CTextBar::OnCreate(LPCREATESTRUCT lpCreateStruct) 
{
	if (CControlBar::OnCreate(lpCreateStruct) == -1)
		return -1;
	
	// 1 - Prepare LOGFONT structure
	CClientDC dc( this );	// need a DC for GetDeviceCaps() below

	LOGFONT lf;				// logical font structure
	::ZeroMemory( &lf, sizeof( lf ) );

	// 24 point Times bold
	lf.lfHeight = - MulDiv( 24, dc.GetDeviceCaps( LOGPIXELSX ), 72 );
	lf.lfWidth			= 0;
	lf.lfEscapement		= 0;
	lf.lfOrientation	= 0;
	lf.lfWeight			= FW_BOLD;
	lf.lfItalic			= FALSE;
	lf.lfUnderline		= FALSE;
	lf.lfStrikeOut		= FALSE;
	lf.lfCharSet		= DEFAULT_CHARSET;
	lf.lfOutPrecision	= OUT_DEFAULT_PRECIS;
	lf.lfClipPrecision	= CLIP_DEFAULT_PRECIS;
	lf.lfQuality		= DEFAULT_QUALITY;
	lf.lfPitchAndFamily	= VARIABLE_PITCH | FF_ROMAN;

	// 2 - Create font
	if( !m_Font.CreateFontIndirect( &lf ) )
	{
		return FALSE;
	}
	
	return 0;
}

void CTextBar::OnPaint() 
{
	CPaintDC dc(this); // device context for painting

	// 1 - Retrieve window text
	CString strText;
	GetWindowText( strText );

	// 2 - Select correct font
	CFont* pOldFont = dc.SelectObject( &m_Font );

	dc.SetBkMode( TRANSPARENT );

	// 3 - Draw text
	dc.TextOut( LEFT_MARGIN, TOP_MARGIN, strText );

	dc.SelectObject( pOldFont );

}

BOOL CTextBar::OnEraseBkgnd(CDC* pDC) 
{
	// 1 - Find out area to erase
	CRect rc;
	pDC->GetClipBox( &rc );

	// 2 - Create the correct brush and select into DC
	CBrush brush( ::GetSysColor( COLOR_BTNFACE ) );
	CBrush* pOldBrush = pDC->SelectObject( &brush );

	// 3 - Erase the background
	pDC->PatBlt(	rc.left, rc.top,
					rc.Width(), rc.Height(),
					PATCOPY );

	pDC->SelectObject( pOldBrush );

	return TRUE;   // Background was erased
}

// ---------------------------------------------------
// CCmdUI and UPDATE_COMMAND_UI processing

// The CTextBarCmdUI is private to this file: its
// only purpose is to make sure that the SetText()
// function is defined to operate correctly on a
// CTextBar object

class CTextBarCmdUI : public CCmdUI
{
public: // re-implementations only
	virtual void SetText(LPCTSTR lpszText);
};

void CTextBarCmdUI::SetText(LPCTSTR lpszText)
{
	// 1 - Get a pointer to our CTextBar object
	CTextBar* pTextBar = (CTextBar*)m_pOther;
	ASSERT(pTextBar != NULL);
	ASSERT_KINDOF(CTextBar, pTextBar);
	ASSERT(m_nIndex < m_nIndexMax);

	// 2 - Change the text bar window's text
	CString strCurrentText;
	pTextBar->GetWindowText(strCurrentText);
	if( strCurrentText != lpszText )	// prevent flicker
	{
		pTextBar->SetWindowText(lpszText);
		pTextBar->Invalidate();
	}
}

void CTextBar::OnUpdateCmdUI(CFrameWnd* pTarget, BOOL bDisableIfNoHndler)
{
	// 1 - Create the CCmdUI object, initialize its members
	CTextBarCmdUI state;
	state.m_pOther = this;
	state.m_nIndex = 0;
	state.m_nIndexMax = 1;	// only one element to update
	state.m_nID = GetDlgCtrlID();

	// 2 - Send CN_UPDATE_COMMAND_UI message to the text bar itself
	if (CWnd::OnCmdMsg(state.m_nID, CN_UPDATE_COMMAND_UI, &state, NULL))
		return;

	// 3 - Send CN_UPDATE_COMMAND_UI message to the owner frame window
	state.DoUpdate(pTarget, FALSE);

	// 4 - Update the dialog controls added to the text bar
	UpdateDialogControls(pTarget, bDisableIfNoHndler);
}