// ComboBoxExt.cpp: implementation of the CComboBoxExt class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "ComboBoxExt.h"
#include "library.h"
#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif
WNDPROC	CComboBoxExt::m_cWndProc = NULL;
DWORD 	CComboBoxExt::m_state;
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////
 LRESULT CComboBoxExt::DefWindowProc( HWND hWnd, UINT message, WPARAM wParam, LPARAM lParam )
 {
 	    CWnd	*pWnd = NULL;
		CPoint	point;
		LRESULT lReturn;
		pWnd = CWnd::FromHandle( hWnd );
		switch( message )
		{
	    case WM_PAINT:
		case WM_NCPAINT:
             lReturn=CallWindowProc( m_cWndProc, hWnd, message, wParam, lParam );
		 	 OnPaint( pWnd );
			 return lReturn;
	    case WM_LBUTTONDOWN:
			m_state |= CXPS_PRESSED;
            lReturn=CallWindowProc( m_cWndProc, hWnd, message, wParam, lParam );
		 	OnPaint( pWnd );
			return lReturn;
		case WM_LBUTTONUP:
			m_state &= ~CXPS_PRESSED;
            lReturn=CallWindowProc( m_cWndProc, hWnd, message, wParam, lParam );
		 	OnPaint( pWnd );
			return lReturn;

		default:
			break;
		}
		return CallWindowProc( m_cWndProc, hWnd, message, wParam, lParam );
	}
  
 	 void CComboBoxExt::OnPaint( CWnd *pWnd )
	{
	  CDC* pDC = pWnd->GetDC();
	  CRect m_rcDropDown;
	  RECT Rect;
	  MEMDCXP Mdcxp;
	  HANDLE hHandle;
	  // 获取窗口大小
	  GetWindowRect(pWnd->GetSafeHwnd (), &Rect);
	  Rect.right -= Rect.left;
	  Rect.bottom -= Rect.top;
	  Rect.top = Rect.left = 0;

      //在WIN98下会把箭头绘到下拉窗口中
      if (Rect.bottom>2*GetSystemMetrics(SM_CYVTHUMB))
		  return;
	  // 获取内存兼容设备场景
	  Mdcxp.hWnd = pWnd->GetSafeHwnd ();
	  Mdcxp.bTransfer = TRUE;
	  Mdcxp.hBitmap = NULL;
	  GetMemDCXP(&Mdcxp);
 //	  DrawScrollBars(pWnd->GetSafeHwnd (), Mdcxp.hMemDC, Rect);//滚动条

	  // 绘制外框
	  FrameRect(Mdcxp.hMemDC, &Rect, (HBRUSH) g_frameedgebrush);

	  // 绘制内框
	  InflateRect(&Rect, -1, -1);

	  hHandle = (HANDLE) ::GetStockObject (WHITE_BRUSH);
      FrameRect(Mdcxp.hMemDC, &Rect, (HBRUSH) hHandle);

	  InflateRect(&Rect, -1, -1);
	  Rect.left = Rect.right - GetSystemMetrics(SM_CYVTHUMB);
	  FrameRect(Mdcxp.hMemDC, &Rect, (HBRUSH) hHandle);
	  Rect.left++;
 	  ScrollDrowThumbXP(Mdcxp.hMemDC, Rect,   m_state | CXPH_DOWNWARDS | CXPH_LARGEARROW);
	  // 还原并释放内存设备场景
	  Mdcxp.bTransfer = TRUE;
	  ReleaseMemDCXP(&Mdcxp); 
	}