透明static控件花屏

对话框A有个button,点击后domodal产生对话框B，B上有几个自绘的透明static控件，开始能正常显示，退出B对话框，再点 Button产生B对话框，如此循环几次后static控件开始花屏，自绘static的代码如下

#include "stdafx.h"

#include "StaticEx.h"



#define _X(x)	(x.left)

#define _Y(x)	(x.top)

#define _W(x)	(x.right - x.left)

#define _H(x)	(x.bottom - x.top)

// CStaticEx



IMPLEMENT_DYNAMIC(CStaticEx, CStatic)



CStaticEx::CStaticEx()

{

	m_clrText  = 0;//RGB( 255, 0, 0 );

	m_clrBkgnd = 0;//RGB( 255, 255, 0 );

	m_hbrBkgnd = NULL;



	m_bTransparent = FALSE;

	m_unIDBmpBkGnd = 0;

}



CStaticEx::~CStaticEx()

{

}



BEGIN_MESSAGE_MAP(CStaticEx, CStatic)

	//{{AFX_MSG_MAP(CTransparentStatic)

	ON_WM_CTLCOLOR_REFLECT()

END_MESSAGE_MAP()



// CStaticEx message handlers



BOOL CStaticEx::SetTransparent(UINT unIDBmpBkGnd, HWND hWnd/* = NULL*/)

{

	m_hbrBkgnd = GetBkBrush(unIDBmpBkGnd, hWnd);

	if (m_hbrBkgnd != NULL)

	{

		m_bTransparent = TRUE;

		Invalidate();

		return TRUE;

	}

	m_bTransparent = FALSE;

	return FALSE;

}





HBRUSH CStaticEx::CtlColor(CDC* pDC, UINT nCtlColor) 

{

	HBRUSH hBr = NULL;



	// 文本颜色

	if (0 == m_clrText)	// 没有自定义文本颜色

	{

		pDC->SetTextColor(GetSysColor(COLOR_WINDOWTEXT));

	}

	else

	{

		pDC->SetTextColor(m_clrText);

	}



	// 背景颜色 绘制背景的刷子

	if (m_bTransparent)			// 透明模式

	{

		pDC->SetBkMode(TRANSPARENT);

		hBr = m_hbrBkgnd;

	}

	else

	{

		if (0 == m_clrBkgnd)	// 没有自定义文本颜色

		{

			pDC->SetBkColor((RGB(255, 255, 255)));

			hBr = (HBRUSH)GetStockObject(WHITE_BRUSH);

		}

		else

		{

			pDC->SetBkColor(m_clrBkgnd);

			hBr = ::CreateSolidBrush(m_clrBkgnd);;

		}

	}



 	return hBr;

}



void CStaticEx::SetClrText(COLORREF clrText)

{

	m_clrText = clrText;

	Invalidate();

}



void CStaticEx::SetClrBkgnd(COLORREF clrBkgnd)

{

	m_clrBkgnd = clrBkgnd;

	Invalidate();

}



void CStaticEx::MoveWindowEx(LPCRECT lpRect, BOOL bRepaint/* = TRUE*/)

{

	if (m_bTransparent)

	{

		MoveWindow(lpRect, FALSE);

		m_hbrBkgnd = GetBkBrush(m_unIDBmpBkGnd);

		Invalidate();

	} 

	else

	{

		MoveWindow(lpRect, bRepaint);

	}

}

HBRUSH CStaticEx::GetBkBrush(UINT unIDBmpBkGnd, HWND hWnd/* = NULL*/)

{

	ASSERT(0 != unIDBmpBkGnd);

	m_unIDBmpBkGnd = unIDBmpBkGnd;



	if (NULL == hWnd)

	{

		hWnd = GetParent()->m_hWnd;

	}

	ASSERT(NULL != hWnd);



	HWND hWndCtrl = this->m_hWnd;

	ASSERT(NULL != hWndCtrl);



	HBITMAP hBmpBk = ::LoadBitmap(AfxGetInstanceHandle(), MAKEINTRESOURCE(unIDBmpBkGnd));

	ASSERT(NULL != hBmpBk);



	HBRUSH	hbrCtrlBk = NULL;



	CRect rcScr;

	::GetClientRect(hWnd, &rcScr);



	CRect rcCtrl;

	::GetWindowRect(hWndCtrl, &rcCtrl);

	::ScreenToClient(hWnd, (LPPOINT)&rcCtrl);

	::ScreenToClient(hWnd, ((LPPOINT)&rcCtrl) + 1);



	CBitmap bitmap;

	bitmap.Attach(hBmpBk);



	BITMAP bi = {0};

	GetObject(bitmap, sizeof(BITMAP), &bi);



	HDC hDC = ::GetDC(hWnd);



	HDC hMemDCBk   = CreateCompatibleDC(hDC);

	HDC hMemDCScr  = CreateCompatibleDC(hDC);

	HDC hMemDCCtrl = CreateCompatibleDC(hDC);



	HBITMAP hBmScr = CreateCompatibleBitmap(hDC, rcScr.Width(), rcScr.Height());

	HBITMAP hBmCtrl = CreateCompatibleBitmap(hDC, rcCtrl.Width(), rcCtrl.Height());



	HBITMAP hBmOldBk   = (HBITMAP)::SelectObject(hMemDCBk, hBmpBk);

	HBITMAP hBmOldScr  = (HBITMAP)::SelectObject(hMemDCScr, hBmScr);

	HBITMAP hBmOldCtrl = (HBITMAP)::SelectObject(hMemDCCtrl, hBmCtrl);



	::StretchBlt(hMemDCScr, 0, 0, rcScr.Width(), rcScr.Height(), hMemDCBk, 0, 0, bi.bmWidth, bi.bmHeight, SRCCOPY);



	::BitBlt(hMemDCCtrl, 0, 0, rcCtrl.Width(), rcCtrl.Height(), hMemDCScr, rcCtrl.left, rcCtrl.top, SRCCOPY);



	::SelectObject(hMemDCCtrl, hBmOldCtrl);

	::SelectObject(hMemDCBk, hBmOldBk);

	::SelectObject(hMemDCScr, hBmScr);



	hbrCtrlBk = ::CreatePatternBrush(hBmCtrl);



	DeleteObject(hBmCtrl);

	DeleteObject(hBmScr);



	::DeleteDC(hMemDCBk);

	::DeleteDC(hMemDCScr);

	::DeleteDC(hMemDCCtrl);

	::ReleaseDC(hWnd, hDC);

	return hbrCtrlBk;

}

B对话框OnInitDialog()调用，m_user为cstaticex对象
m_user.SubclassDlgItem(IDC_STATIC_USER1, this);
m_user.SetTransparent(7172);
m_user.SetClrText(RGB(255,255,255));