snapdlg.cpp

C++开发的可停靠的的窗口实例

// SnapDlg.cpp: implementation of the CSnapDlg class.
//
/*
Copyright 2001 Anish Mistry. All rights reserved.

Redistribution and use in source and binary forms, with or without modification,
are permitted provided that the following conditions are met:

   1. Redistributions of source code must retain the above copyright notice, 
   this list of conditions and the following disclaimer.
   2. Redistributions in binary form must reproduce the above copyright notice,
   this list of conditions and the following disclaimer in the documentation 
   and/or other materials provided with the distribution.

THIS SOFTWARE IS PROVIDED BY ANISH MISTRY ``AS IS'' AND ANY EXPRESS OR IMPLIED 
WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY 
AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS 
OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

The views and conclusions contained in the software and documentation are those
of the authors and should not be interpreted as representing official policies,
either expressed or implied, of Anish Mistry or AM Productions.

* Variation of the FreeBSD License. http://www.freebsd.org/copyright/freebsd-license.html
*/
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "SnapDlg.h"

//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CSnapDlg::CSnapDlg()
{
	m_szMoveOffset.cx = 0;
	m_szMoveOffset.cy = 0;
	// snap pixels
	m_nSnapPixels = 5;
	// get the desktop rectangle for snappyness
	GetWindowRect(GetDesktopWindow(),&m_rDesktopRect);
}

CSnapDlg::~CSnapDlg()
{

}

LRESULT CSnapDlg::DlgProc(HWND hDlg,UINT nMessage,WPARAM wParam,LPARAM lParam)
{// begin DlgProc
	switch (nMessage) 
	{
	case WM_MOVING:
		OnMoving(wParam,lParam);
		break;
	case WM_NCLBUTTONDOWN:
		OnNcLButtonDown(wParam,lParam);
		break;
	}
	return CMyDialog::DlgProc(hDlg,nMessage,wParam,lParam);
}// end DlgProc

void CSnapDlg::OnMoving(WPARAM &wParam,LPARAM &lParam)
{// begin OnMoving
	RECT *pRect = (RECT *)lParam;
	// calculate window size
	SIZE szSize = {pRect->right-pRect->left,pRect->bottom-pRect->top};
	POINT pt = {NULL};
	GetCursorPos(&pt);
	pRect->left = pt.x-m_szMoveOffset.cx;
	pRect->top = pt.y-m_szMoveOffset.cy;
	pRect->right = pRect->left+szSize.cx;
	pRect->bottom = pRect->top+szSize.cy;
	// snap window to screen edges
	if(pRect->top < m_nSnapPixels && pRect->top > -m_nSnapPixels)
	{// begin snap to top
		pRect->top = 0;
		pRect->bottom = szSize.cy;
	}// end snap to top
	if(pRect->left < m_nSnapPixels && pRect->left > -m_nSnapPixels)
	{// begin snap to left
		pRect->left = 0;
		pRect->right = szSize.cx;
	}// end snap to left
	if(pRect->right < m_rDesktopRect.right+m_nSnapPixels && pRect->right > m_rDesktopRect.right-m_nSnapPixels)
	{// begin snap to right
		pRect->right = m_rDesktopRect.right;
		pRect->left = m_rDesktopRect.right-szSize.cx;
	}// end snap to right
	if(pRect->bottom < m_rDesktopRect.bottom+m_nSnapPixels && pRect->bottom > m_rDesktopRect.bottom-m_nSnapPixels)
	{// begin snap to bottom
		pRect->bottom = m_rDesktopRect.bottom;
		pRect->top = m_rDesktopRect.bottom-szSize.cy;
	}// end snap to bottom
}// end OnMoving

void CSnapDlg::OnNcLButtonDown(WPARAM wParam,LPARAM lParam)
{// begin OnNcLButtonDown
	if(wParam == HTCAPTION)
	{// begin save mouse coord
		// calculate drag offset
		POINT pt = {LOWORD(lParam),HIWORD(lParam)};
		RECT rRect = {NULL};
		GetWindowRect(m_hDlg,&rRect);
		m_szMoveOffset.cx = pt.x-rRect.left;
		m_szMoveOffset.cy = pt.y-rRect.top;
	}// end save mouse coord
}// end OnNcLButtonDown

void CSnapDlg::OnDisplayChange(void)
{// begin OnDisplayChange
	// get the new desktop rectangle
	GetWindowRect(GetDesktopWindow(),&m_rDesktopRect);
}// end OnDisplayChange