求非HOOK方式自绘CListViewCtrl滚动条的办法???

Sou2012 2010-03-24 05:33:22

一直在做一个 CListViewCtrl 的自绘滚动条，但是我现在想到的，就是以下代码。

下面我实现的，不能拖着滚动条上下移动。有没有人帮我完善一下。非常感谢。

#pragma once



#define WM_UPDATE_SCROLL_BAR_THUMB_HEIGHT (WM_USER + 300)



#define CUSTOM_SCROLL_BAR_THUMB_MIN_HEIGHT 10



class CCustomScrollbar : public CWindowImpl<CCustomScrollbar>

	//template <class T, class TBase = CStatic, class TWinTraits = CControlWinTraits>

	//class CCustomScrollbarImpl : public CWindowImpl<T, TBase, TWinTraits>

{

public:

	BEGIN_MSG_MAP(CCustomScrollbar)

		MSG_WM_PAINT(OnPaint)

		MSG_WM_ERASEBKGND(OnEraseBkgnd)



		MSG_WM_LBUTTONDOWN(OnLButtonDown)

		MSG_WM_LBUTTONUP(OnLButtonUp)

		MSG_WM_MOUSEMOVE(OnMouseMove)

	END_MSG_MAP()

public:

	CCustomScrollbar()

	{

		m_nThumbTop = 0;

		m_nThumbHeight = CUSTOM_SCROLL_BAR_THUMB_MIN_HEIGHT;

		m_dbThumbInterval = 0;



		m_bMouseDown = false;

	}

	void InitScrollBarRect()

	{

		m_upBtnRect = CRect(CPoint(0, 0), CSize(16, 16));

		m_thumbBtnRect = CRect(CPoint(0, m_nThumbTop), CSize(16, m_nThumbHeight));

		m_downBtnRect = CRect(CPoint(0, 515 - 16), CSize(16, 16));

	}

public:

	BOOL OnEraseBkgnd(CDCHandle dc)

	{

		return TRUE;

	}



	void OnPaint(CDCHandle dc)

	{

		CRect rect;

		GetClientRect(&rect);



		CPaintDC paintDC(m_hWnd);

		CMemoryDC memDC(paintDC, rect);

		DoPaintEx(memDC);

	}



	void DoPaintEx(CMemoryDC &memDC)

	{

		InitScrollBarRect();



		CRect rect;

		GetClientRect(&rect);



		memDC.FillSolidRect(&rect, RGB(74,82,107));



		CImage img;



		// draw bg

		img.LoadFromResource(_Module.GetResourceInstance(), IDB_SCROLL_BAR_BG);

		img.Draw(memDC, rect);

		img.Destroy();



		// draw up btn		

		img.LoadFromResource(_Module.GetResourceInstance(), IDB_SCROLL_BAR_UP_BTN);

		img.Draw(memDC, rect.left, rect.top, 16, 16);

		img.Destroy();



		DrawThumbBtn(memDC, rect, img);		



		// draw down btn

		img.LoadFromResource(_Module.GetResourceInstance(), IDB_SCROLL_BAR_DOWN_BTN);

		img.Draw(memDC, rect.left, rect.bottom - 16, 16, 16);

		img.Destroy();

	}



	void DrawThumbBtn(CMemoryDC &memDC, CRect &rect, CImage &img)

	{

		// _nThumbHeight Min is 5 = 2 * 2 + 1 ( 4 is thumb_up + thumb_down, 2 + 2), 1 is offet

		if (m_nThumbHeight >= 5)

		{

			// 上半块 紧贴 在 UP BTN 的下面

			img.LoadFromResource(_Module.GetResourceInstance(), IDB_SCROLL_BAR_THUMB);

			img.Draw(memDC, rect.left, rect.top + 16 + m_nThumbTop, img.GetWidth(), 2,

				0, 0, img.GetWidth(), 2);

			img.Destroy();



			// 中间块

			img.LoadFromResource(_Module.GetResourceInstance(), IDB_SCROLL_BAR_THUMB);

			img.Draw(memDC, rect.left, rect.top + 16 + 2 + (m_nThumbTop), img.GetWidth(), m_nThumbHeight - 2 - 2,

				0, 2, img.GetWidth(), img.GetHeight() - 2 - 2);

			img.Destroy();



			// 下半块

			img.LoadFromResource(_Module.GetResourceInstance(), IDB_SCROLL_BAR_THUMB);

			img.Draw(memDC, rect.left, rect.top + 16 + 2 + (m_nThumbHeight - 2 - 2) + (m_nThumbTop), img.GetWidth(), 2,

				0, 14, img.GetWidth(), 2);

			img.Destroy();

		}		

	}



	void OnLButtonDown(UINT nFlags, CPoint point)

	{

		m_bMouseDown = true;		

	}



	void OnLButtonUp(UINT nFlags, CPoint point)

	{

		CRect rect;

		GetClientRect(&rect);

		if (m_bMouseDown)

		{

			if (m_upBtnRect.PtInRect(point))

			{

				LineUp();		

			}

			else if (m_thumbBtnRect.PtInRect(point))

			{

				//ThumbPosition

			}

			else if (m_downBtnRect.PtInRect(point))

			{

				LineDown();

			}

			else if (rect.PtInRect(point)) 

			{

				if (point.y < m_thumbBtnRect.top)

				{

					PageUp();

				}

				else if (point.y >= m_thumbBtnRect.bottom)

				{

					PageDown();

				}		

			}

			m_bMouseDown = false;

		}

		Invalidate();

	}



	void OnMouseMove(UINT nFlags, CPoint point)

	{

		if (m_bMouseDown)

		{

			m_nThumbTop = point.y;

			Invalidate();

		}

	}

public:

	void PageUp()

	{

		m_pListViewCtrl->SendMessage(WM_VSCROLL, MAKELONG(SB_PAGEUP, 0), NULL);

		UpdateThumbPosition();

	}



	void PageDown()

	{

		m_pListViewCtrl->SendMessage(WM_VSCROLL, MAKELONG(SB_PAGEDOWN,0), NULL);

		UpdateThumbPosition();

	}	



	void LineUp()

	{

		m_pListViewCtrl->SendMessage(WM_VSCROLL, MAKELONG(SB_LINEUP, 0), NULL);

		UpdateThumbPosition();

	}



	void LineDown()

	{

		m_pListViewCtrl->SendMessage(WM_VSCROLL, MAKELONG(SB_LINEDOWN, 0), NULL);

		UpdateThumbPosition();

	}

public:

	void UpdateThumbPosition()

	{

		m_pListViewCtrl->SendMessage(WM_UPDATE_SCROLL_BAR_THUMB_HEIGHT, 0, 0);

		CRect rect;

		GetClientRect(&rect);



		SCROLLINFO si;

		si.cbSize = sizeof(si);

		si.fMask = SIF_POS | SIF_PAGE | SIF_RANGE;

		m_pListViewCtrl->GetScrollInfo(SB_VERT, &si);



		double dbPos = si.nPos;

		double dbPageSize = si.nPage;

		double dbMax = si.nMax;



		// 屏幕高度 = rect.Height() - 2个(up,down)按钮的高度 - 滚动框本身的高度

		double dbHeight = rect.Height() - (2 * 16) - m_nThumbHeight;



		// 滚动框每次移动的间距 = 屏幕高度 / (滚动的最大值 - 页面大小)

		// 这里每次都计算是因为 如果 InsertItem 这个间距就变化了

		m_dbThumbInterval = dbHeight / (dbMax - dbPageSize);



		// 设置 (滚动框top) 的最终位置 = 间距 * 当前位置

		m_nThumbTop = m_dbThumbInterval * dbPos;

		InitScrollBarRect();

	}



	void SetThumbHeight(int height)

	{

		if (height > CUSTOM_SCROLL_BAR_THUMB_MIN_HEIGHT)

		{

			m_nThumbHeight = height;	

		}		

	}

public:

	CListViewCtrl *m_pListViewCtrl;

private:

	CRect m_upBtnRect;

	CRect m_thumbBtnRect;	

	CRect m_downBtnRect;	

private:

	bool m_bMouseDown;



	int m_nThumbHeight;

	double m_dbThumbInterval;

	int m_nThumbTop;

};