// 透明窗口View.cpp : implementation of the CMyView class
//

#include "stdafx.h"
#include "透明窗口.h"

#include "透明窗口Doc.h"
#include "透明窗口View.h"

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

/////////////////////////////////////////////////////////////////////////////
// CMyView

IMPLEMENT_DYNCREATE(CMyView, CView)

BEGIN_MESSAGE_MAP(CMyView, CView)
	//{{AFX_MSG_MAP(CMyView)
	ON_WM_CREATE()
	ON_WM_PAINT()
	//}}AFX_MSG_MAP
END_MESSAGE_MAP()

/////////////////////////////////////////////////////////////////////////////
// CMyView construction/destruction

CMyView::CMyView()
{
	// TODO: add construction code here

}

CMyView::~CMyView()
{
	memDC.SelectObject(oldObject);//釋放資源
    memDC.DeleteDC();
}

BOOL CMyView::PreCreateWindow(CREATESTRUCT& cs)
{
	// TODO: Modify the Window class or styles here by modifying
	//  the CREATESTRUCT cs

	//將客戶(hù)區(qū)窗口的刷子該為空刷子
	return CView::PreCreateWindow(cs);
}

/////////////////////////////////////////////////////////////////////////////
// CMyView drawing

void CMyView::OnDraw(CDC* pDC)
{
	CMyDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);
	// TODO: add draw code for native data here
}

/////////////////////////////////////////////////////////////////////////////
// CMyView diagnostics

#ifdef _DEBUG
void CMyView::AssertValid() const
{
	CView::AssertValid();
}

void CMyView::Dump(CDumpContext& dc) const
{
	CView::Dump(dc);
}

CMyDoc* CMyView::GetDocument() // non-debug version is inline
{
	ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CMyDoc)));
	return (CMyDoc*)m_pDocument;
}
#endif //_DEBUG

/////////////////////////////////////////////////////////////////////////////
// CMyView message handlers

int CMyView::OnCreate(LPCREATESTRUCT lpCreateStruct) 
{
	if (CView::OnCreate(lpCreateStruct) == -1)
		return -1;
	//CWnd* mainfraim;
    //  mainfraim=AfxGetMainWnd();
	//mainfraim->SetActiveWindow();	
	// TODO: Add your specialized creation code here
	::SetClassLong(this->m_hWnd,GCL_HBRBACKGROUND,(long)GetStockObject(HOLLOW_BRUSH));
	width=GetSystemMetrics(SM_CXSCREEN);//保存當(dāng)前顯示器的分辨率
	height=GetSystemMetrics(SM_CYSCREEN);
	CWindowDC screenDC(NULL);//獲得屏幕窗口的上下文
//初始化位圖
	hbmp.CreateBitmap(width,height,screenDC.GetDeviceCaps(PLANES),screenDC.GetDeviceCaps(BITSPIXEL),NULL);
    
    memDC.CreateCompatibleDC(NULL);
	
    oldObject=memDC.SelectObject(&hbmp);
    memDC.BitBlt(0,0,width,height,&screenDC,0,0,SRCCOPY);

	return 0;
}

void CMyView::OnPaint() 
{
	CPaintDC dc(this); // device context for painting
	
	// TODO: Add your message handler code here
	
	RECT clientRect;
	GetClientRect(&clientRect);//獲得當(dāng)前客戶(hù)區(qū)的大小
	POINT lefttop;

	lefttop.x=clientRect.left;
	lefttop.y=clientRect.top;

	ClientToScreen(&lefttop);//將窗口客戶(hù)區(qū)左上角的點(diǎn)坐標(biāo)轉(zhuǎn)換為屏幕坐標(biāo)
			           //用保存的位圖將客戶(hù)區(qū)重畫(huà)
	dc.BitBlt(0,0,clientRect.right,clientRect.bottom,&memDC,lefttop.x,lefttop.y,SRCCOPY);
	dc.TextOut(100,0,"Hello world");
	
	// Do not call CView::OnPaint() for painting messages
}