// ScrollBarExt.cpp: implementation of the CScrollBarExt class.
//
//////////////////////////////////////////////////////////////////////

#include "stdafx.h"
#include "ScrollBarExt.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[]=__FILE__;
#define new DEBUG_NEW
#endif
WNDPROC	CScrollBarExt::m_cWndProc = NULL;
int	CScrollBarExt::pos = 0;
//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

	 LRESULT CScrollBarExt::DefWindowProc( HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam )
	{
		switch( message )
		{
	    case WM_PAINT:
	    case WM_NCPAINT:
 	    case WM_LBUTTONDOWN:
	    case WM_LBUTTONUP:
	    case WM_MOUSEMOVE:
			CallWindowProc( m_cWndProc, hwnd, message, wParam, lParam );
		//	ShowWindow(hwnd, SW_HIDE);
		   OnPaint(hwnd);
		   return 0;
		case WM_ERASEBKGND:
			return 1;
	    default:
			break;
		}
		return CallWindowProc( m_cWndProc, hwnd, message, wParam, lParam );
	}
	 
 	 void CScrollBarExt::OnPaint( HWND hWnd )
	{
		RECT rcItem;
		HDC hdc=GetWindowDC(hWnd);
		GetWindowRect(hWnd, &rcItem);
		rcItem.right -=rcItem.left ;
		rcItem.bottom -=rcItem.top ;
		rcItem.top =rcItem.left =0;
        const int nFrameSize  = GetSystemMetrics( SM_CXEDGE ); 
        const int nScrollSize = GetSystemMetrics( SM_CXHSCROLL );   
        RECT rc; 
	    if(rcItem.right >rcItem.bottom )//根据滚动的长宽判断是水平还是垂直..水平
		{
          rc.left = rcItem.left + nFrameSize;
		  rc.top = rcItem.bottom - nFrameSize - nScrollSize;
          rc.right = rcItem.right - nFrameSize; 
		  rc.bottom = rcItem.bottom - nFrameSize;
          DrawScrollBar(hWnd, hdc, rc, SB_HORZ, 1 );
		}
	    else
		{    
		   rc.left = rcItem.right - nFrameSize - nScrollSize; rc.top = rcItem.top + nFrameSize;
           rc.right = rcItem.right - nFrameSize; rc.bottom = rcItem.bottom - nFrameSize;
           DrawScrollBar(hWnd, hdc, rc, SB_VERT, 1 );
		}
	}