TreeCtrl的使用和一个CTreeCtrl的派生类
1.树视图风格:
TVS_HASBUTTONS; //在父项旁边显示(+)和(-)
TVS_HASLINES; //使用线条显示各项之间的层次
TVS_LINESATROOT;//使用线条链接树视图控件根部各项
2.处理单击事件:TVN_SELCHANGED
void CTreeCtrlDlg::OnTvnSelchangedTree1(NMHDR *pNMHDR, LRESULT *pResult)
{
LPNMTREEVIEW pNMTreeView = reinterpret_cast
// TODO: 在此添加控件通知处理程序代码
HTREEITEM ht=m_treeCtrl.GetSelectedItem();
CString strSelect=m_treeCtrl.GetItemText(ht);
m_strTreeVal=strSelect;
UpdateData(FALSE);
*pResult = 0;
}
3.同时让自己派生的CMyTreeCtrl类和对话框处理TVN_SELCHANGED消息:
只须在CMyTreeCtrl中处理以下消息,并返回FALSE就OK了ON_NOTIFY_REFLECT_EX(TVN_SELCHANGED, OnTvnSelchanged) OnTvnSelchanged的签名如下
BOOL CMyTreeCtrl::OnTvnSelchanged(NMHDR *pNMHDR,LRESULT *pResult)
4.编辑标签:要允许编辑树视图控件中的文本,可以设置以下三个步骤
1.设置树视图的TVS_EDITLABELS风格
TVS_EDITLABE可以通过资源编辑框内部修改(Edit labels),也可以用代码的方式修改,如下
long lStyle=::GetWindowLong(m_treeCtrl.GetSafeHwnd(),GWL_STYLE);
lStyle|=TVS_EDITLABELS;
::SetWindowLong(m_treeCtrl.GetSafeHwnd(),GWL_STYLE,lStyle)
2.处理TVN_BEGINLABELEDIT通知消息
//设置相关限制,如限制编辑框字符串长度
CEdit*pEdit=GetEditControl(); //获取当前选中结点编辑框
ASSERT(pEdit);
if (pEdit)
{
pEdit->LimitText(15);//设置编辑框文本长度为15个字符串
*pResult = 0;
}
3.处理TVN_ENDLABLEEDIT通知消息
HTREEITEM hParent=GetParentItem(pTVDispInfo->item.hItem); //获取父结点
HTREEITEM hChild=GetChildItem(hParent?hParent:TVI_ROOT); //获取第一个根结点
hChild=GetNextSiblingItem(hChild); //获取下一个兄弟节点
if (pTVDispInfo->item.hItem!=hChild) //判断是否与当前节点相同
pTVDispInfo->item.pszText //获取当前节点的字符串
CString strText=GetItemText(hChild); //获取节点的字符串
3.让树视图处理Esc和Enter键
重载PreTranslateMessage函数
BOOL bHandleMsg=FALSE;
switch(pMsg->message) {
case VK_ESCAPE:
case VK_RETURN:
if (::GetKeyState(VK_CONTROL)&0x8000)
{
break;
}
if (GetEditControl())
{
::TranslateMessage(pMsg);
::DispatchMessage(pMsg);
bHandleMsg=TRUE;
}
break;
}
4.实现上下文菜单
在WM_RBUTTONDOWN消息处理函数上实现上下文菜单
5.展开和收起树视图结点:
HTREEITEM hItem=GetRootItem(); //获取根结点,可能会有多个根结点
ItemHasChildren(hParent) //判断结点是否有孩子结点
hItem=GetChildItem(hParent); //获取第一个子结点
hItem=GetNextSiblingItem(hItem)); //获取下一个兄弟结点结点
Expand(hItem,bExpand?TVE_EXPAND:TVE_COLLAPSE);//展开/叠起结点
Select(hItem,TVGN_FIRSTVISIBLE); //设置选中结点
CString str=GetItemText(hChild); //获取结点字符串信息
HTREEITEM hCurrSel = GetSelectedItem(); //获取当前选中结点
SelectItem(hNewSel);
HTREEITEM hNewSel = HitTest(pt, &nFlags); //判断坐标是否在当前结点范围内
HTREEITEM hItem=InsertItem(dlg.m_strItemText,hItemParent); //插入结点
#pragma once
//定义文件MyTreeCtrl.h
// CMyTreeCtrl
class CMyTreeCtrl : public CTreeCtrl
{
DECLARE_DYNAMIC(CMyTreeCtrl)
public:
CMyTreeCtrl();
virtual ~CMyTreeCtrl();
protected:
DECLARE_MESSAGE_MAP()
void ExpandBranch(HTREEITEM hItem,BOOL bExpand =TRUE);
public:
void ExpandAllBranches(BOOL bExpand =TRUE);
BOOL DoesItemExist(HTREEITEM hItemParent, CString const& strItem);
afx_msg void OnRButtonDown(UINT nFlags, CPoint point);
afx_msg void OnAddItem();
virtual BOOL PreTranslateMessage(MSG* pMsg);
afx_msg void OnTvnBeginlabeledit(NMHDR *pNMHDR, LRESULT *pResult);
afx_msg void OnTvnEndlabeledit(NMHDR *pNMHDR, LRESULT *pResult);
afx_msg BOOL OnTvnSelchanged(NMHDR *pNMHDR, LRESULT *pResult);
};
// MyTreeCtrl.cpp : 实现文件
//
#include "stdafx.h"
#include "TreeCtrl.h"
#include "MyTreeCtrl.h"
#include "./mytreectrl.h"
#include "AddItemDlg.h"
// CMyTreeCtrl
IMPLEMENT_DYNAMIC(CMyTreeCtrl, CTreeCtrl)
CMyTreeCtrl::CMyTreeCtrl()
{
}
CMyTreeCtrl::~CMyTreeCtrl()
{
}
BEGIN_MESSAGE_MAP(CMyTreeCtrl, CTreeCtrl)
ON_WM_RBUTTONDOWN()
ON_COMMAND(IDR_ADD_ITEM, OnAddItem)
ON_NOTIFY_REFLECT(TVN_ENDLABELEDIT, OnTvnEndlabeledit)
ON_NOTIFY_REFLECT(TVN_BEGINLABELEDIT, OnTvnBeginlabeledit)
ON_NOTIFY_REFLECT_EX(TVN_SELCHANGED, OnTvnSelchanged)
END_MESSAGE_MAP()
// CMyTreeCtrl 消息处理程序
void CMyTreeCtrl::ExpandBranch(HTREEITEM hItem,BOOL bExpand /* =TRUE */)
//展开
{
if (ItemHasChildren(hItem)) //判断是否有孩子结点
{
Expand(hItem,bExpand?TVE_EXPAND:TVE_COLLAPSE);
//展开/叠起结点
hItem=GetChildItem(hItem);//获取第一个子结点
do {
ExpandBranch(hItem);
} while(hItem=GetNextSiblingItem(hItem));//获取兄弟结点
}
}
void CMyTreeCtrl::ExpandAllBranches(BOOL bExpand /* =TRUE */)
{
HTREEITEM hItem=GetRootItem();//获取根结点,可能会有多个根结点
do {
ExpandBranch(hItem,bExpand);
} while(hItem=GetNextSiblingItem(hItem));
Select(hItem,TVGN_FIRSTVISIBLE);//设置选中结点
}
BOOL CMyTreeCtrl::DoesItemExist(HTREEITEM hItemParent,
CString const& strItem)
{
BOOL bDoesItemExist=FALSE;
ASSERT(strItem.GetLength());
HTREEITEM hChild=GetChildItem(hItemParent?hItemParent:TVI_ROOT);
while (NULL!=hChild&&!bDoesItemExist)
{
CString str=GetItemText(hChild);//获取结点字符串信息
if (0==str.CompareNoCase(strItem))
{
bDoesItemExist=TRUE;
}
else
{
hChild=GetNextSiblingItem(hChild);
}
}
return bDoesItemExist;
}
void CMyTreeCtrl::OnRButtonDown(UINT nFlags, CPoint point)
{
// TODO: 在此添加消息处理程序代码和/或调用默认值
// set focus to the tree control
SetFocus();
// map the point that is passed to the
// function from client coordinates
// to screen coordinates
ClientToScreen(&point);
// Get the currently selected item
HTREEITEM hCurrSel = GetSelectedItem();//获取当前选中结点
// Figure out which item was right clicked
CPoint pt(0, 0);
::GetCursorPos(&pt);
ScreenToClient (&pt);
HTREEITEM hNewSel = HitTest(pt, &nFlags);
// Set the selection to the item that the
// mouse was over when the user right
// clicked
if (NULL == hNewSel)
{
SelectItem(NULL);
}
else if (hCurrSel != hNewSel)
{
SelectItem(hNewSel);
SetFocus();
}
// Load the context menu
CMenu Menu;
if (Menu.LoadMenu(IDM_CONTEXT_MENU))
{
CMenu* pSubMenu = Menu.GetSubMenu(0);
if (pSubMenu!=NULL)
{
// Display the context menu
pSubMenu->TrackPopupMenu(
TPM_LEFTALIGN | TPM_RIGHTBUTTON,
point.x, point.y, this);
}
}
}
void CMyTreeCtrl::OnAddItem()
//添加上下文菜单
{
// TODO: 在此添加命令处理程序代码
HTREEITEM hItemParent=GetSelectedItem();
//获取当前选中结点
CAddItemDlg dlg;
if (dlg.DoModal()==IDOK)
{
if (!DoesItemExist(hItemParent,dlg.m_strItemText))
{
HTREEITEM hItem=InsertItem(dlg.m_strItemText,hItemParent);
//插入结点
SelectItem(hItem);
}
else
{
AfxMessageBox("已存在相同结点");
}
}
}
BOOL CMyTreeCtrl::PreTranslateMessage(MSG* pMsg)
{
// TODO: 在此添加专用代码和/或调用基类
BOOL bHandledMsg = FALSE;
switch (pMsg->message)
{
case WM_KEYDOWN:
{
switch (pMsg->wParam)
{
case VK_ESCAPE:
case VK_RETURN:
if (::GetKeyState(VK_CONTROL) & 0x8000)
{
break;
}
if (GetEditControl())
{
::TranslateMessage(pMsg);
::DispatchMessage(pMsg);
bHandledMsg = TRUE;
}
break;
default: break;
} // switch (pMsg->wParam)
} // WM_KEYDOWN
break;
default: break;
} // switch (pMsg->message)
// continue normal translation and dispatching
return (bHandledMsg ?TRUE : CTreeCtrl::PreTranslateMessage(pMsg));
}
void CMyTreeCtrl::OnTvnBeginlabeledit(NMHDR *pNMHDR, LRESULT *pResult)
{
LPNMTVDISPINFO pTVDispInfo = reinterpret_cast
// TODO: 在此添加控件通知处理程序代码
*pResult=1;
CEdit*pEdit=GetEditControl();
ASSERT(pEdit);
if (pEdit)
{
pEdit->LimitText(15);
*pResult=0;
}
}
void CMyTreeCtrl::OnTvnEndlabeledit(NMHDR *pNMHDR, LRESULT *pResult)
{
LPNMTVDISPINFO pTVDispInfo = reinterpret_cast
// TODO: 在此添加控件通知处理程序代码
BOOL bValidItem=FALSE;
CString strItem=pTVDispInfo->item.pszText;
if (0
{
HTREEITEM hParent=GetParentItem(pTVDispInfo->item.hItem);
bValidItem=!DoesItemExist(hParent,strItem);
}
*pResult = bValidItem;
}
BOOL CMyTreeCtrl::OnTvnSelchanged(NMHDR *pNMHDR, LRESULT *pResult)
{
LPNMTREEVIEW pNMTreeView = reinterpret_cast
// TODO: 在此添加控件通知处理程序代码
TRACE(GetItemText(pNMTreeView->itemNew.hItem));
TRACE("/n");
*pResult = 0;
return FALSE; //返回FALSE可以让父窗口进行进一步的处理
}