【原创】纯VC++ 实现不等高CTreeCtrl（可用于好友列表）

来源：互联网发布：爱奇艺扫号器一手数据编辑：程序博客网时间：2024/06/07 02:15

首先看图： demo

收缩“我的大学”

实现方法：

自绘控件。

步骤：

1、#include <afxtempl.h> 我们需要一个CList来管理哪些子项要被画出来，因此我们需要定义 CList<HTREEITEM* ,HTREEITEM*> m_TreeItemList;

2、有了m_TreeItemList，我们需要得到这些子项，有函数void GetList();

3、自绘时，原来的CTreeCtrl之中的函数如HitTest我们要换成自己的HitTestEx（）；

4、OnNMClick实现展开收缩父节点；

5、OnVScroll之中实现滚动条拖放，先得到需要画的总高度和客户区的总高度；

6、OnPaint中实现自绘，绘图时要注意当前vscrollbar的位置

7、OnNMDblclk、OnNMRclick、OnNMRclick、OnNMRdblclk中*pResult = TRUE；屏蔽展开收缩用我们自己的方法

部分代码：

void CYYTreeCtrl::GetList(){DestroyList();HTREEITEM hItem = GetNextItem(NULL,TVGN_CHILD);if(hItem == NULL)return;GetToDrawItemList(hItem);}void CYYTreeCtrl::GetToDrawItemList( HTREEITEM hItem ){UINT nState = GetItemState(hItem, TVIS_EXPANDED); BOOL bIsExpended = nState & TVIS_EXPANDED;HTREEITEM* newHtreeItem = new HTREEITEM(hItem);m_TreeItemList.AddTail(newHtreeItem);if(bIsExpended){HTREEITEM hChildItem = GetNextItem(hItem,TVGN_CHILD);GetToDrawItemList(hChildItem);}HTREEITEM hNextItem = GetNextItem(hItem,TVGN_NEXT);if(hNextItem != NULL)GetToDrawItemList(hNextItem);}void CYYTreeCtrl::DestroyList(){POSITION pos = m_TreeItemList.GetHeadPosition();for(int i = 0;i < m_TreeItemList.GetCount();i++){HTREEITEM* pItem = m_TreeItemList.GetNext(pos);delete pItem;}m_TreeItemList.RemoveAll();}HTREEITEM CYYTreeCtrl::HitTestEx( CPoint pt ){GetClientRect(&m_rect);GetList();int nScrollPos = GetScrollPos(SB_VERT);int nHeight = -nScrollPos;POSITION pos = m_TreeItemList.GetHeadPosition();for(int i = 0;i < m_TreeItemList.GetCount();i++){HTREEITEM* pItem = m_TreeItemList.GetAt(pos);if(ItemHasChildren(*pItem))nHeight += PARENT_HEIGHT;elsenHeight += CHILD_HEIGHT;if( nHeight >= pt.y)return *pItem;m_TreeItemList.GetNext(pos);}return NULL;}void CYYTreeCtrl::OnVScroll(UINT nSBCode, UINT nPos, CScrollBar* pScrollBar){// TODO: 在此添加消息处理程序代码和/或调用默认值int nScrollPos = GetScrollPos(SB_VERT);int nLimit = GetScrollLimit(SB_VERT);int nScroll = nLimit;int SCROLL_AMT_Y = 50;switch(nSBCode) {case SB_LINEUP: // Scroll up. case SB_PAGEUP:if(nScrollPos <= 0){return;}nScroll = min(nScrollPos,SCROLL_AMT_Y);SetScrollPos(SB_VERT,nScrollPos - nScroll);break; case SB_LINEDOWN: // Scroll down.case SB_PAGEDOWN:if(nScrollPos >= nLimit){return;}nScroll = min(nScroll-nScrollPos,SCROLL_AMT_Y);SetScrollPos(SB_VERT,nScrollPos + nScroll);//ScrollWindow(5,0);break;case SB_THUMBPOSITION:{HWND hWndScroll;if ( pScrollBar == NULL )hWndScroll = m_hWnd;elsehWndScroll = pScrollBar->m_hWnd;SCROLLINFO info;info.cbSize = sizeof(SCROLLINFO);info.fMask = SIF_TRACKPOS;::GetScrollInfo(hWndScroll, SB_VERT, &info);nPos = info.nTrackPos;int nScr = nScrollPos - nPos;SetScrollPos(SB_VERT,nPos);}break;case SB_THUMBTRACK:{HWND hWndScroll;if ( pScrollBar == NULL )hWndScroll = m_hWnd;elsehWndScroll = pScrollBar->m_hWnd;SCROLLINFO info;info.cbSize = sizeof(SCROLLINFO);info.fMask = SIF_TRACKPOS;::GetScrollInfo(hWndScroll, SB_VERT, &info);nPos = info.nTrackPos;int nScr = nScrollPos - nPos;SetScrollPos(SB_VERT,nPos,FALSE);}break;}Invalidate();CTreeCtrl::OnVScroll(nSBCode, nPos, pScrollBar);}void CYYTreeCtrl::OnNMClick(NMHDR *pNMHDR, LRESULT *pResult){// TODO: 在此添加控件通知处理程序代码HTREEITEM hItem;CPoint pt;GetCursorPos(&pt); //获得屏幕光标坐标ScreenToClient(&pt);//转换到树hItem = HitTestEx(pt);m_hItemSelect = hItem;Expand(hItem,TVE_TOGGLE);int nTotalHeight = CalclateTotalHeight();int nCount = CalculateVisableItemCount();GetClientRect(&m_rect);SCROLLINFO scrlinfo;scrlinfo.cbSize = sizeof(scrlinfo);scrlinfo.fMask = SIF_PAGE|SIF_RANGE;scrlinfo.nMax = nTotalHeight;scrlinfo.nMin = 0;scrlinfo.nPage = m_rect.Height();scrlinfo.nPos = 0;SetScrollInfo(SB_VERT,&scrlinfo);Invalidate();*pResult = TRUE;}

源代码：自己在做类似QQ的聊天工具，目前代码正在进行中，如果您想要此部分代码

http://download.csdn.net/source/3388865

BUG请联系QQ:287909254

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