Wpf Datagrid列集合已更改事件

我使用此代码从datagrid中添加或删除列。每个列标题我都有鼠标进入和离开事件。对于新列，我还希望在插入到datagrid之后添加相同的事件处理程序

    private void Columns_CollectionChanged(object sender, System.ComponentModel.CollectionChangeEventArgs e)
     {
        if (e.Action == CollectionChangeAction.Add)
        {
            int columnPosition = (this.Columns.Count - 1);
            DataGridTextColumn column = new DataGridTextColumn();
            column.Header = (e.Element as DataColumn).ColumnName;
            column.Binding = new Binding(string.Format("[{0}]", column.Header.ToString()));
            this.Columns.Insert(columnPosition, column);

            DataGridColumnHeader columnHeader = DataGridHelper.GetColumnHeader(this, columnPosition);
            if (columnHeader != null)
            {
                columnHeader.MouseEnter += new MouseEventHandler(ColumnHeader_MouseEnter);
                columnHeader.MouseLeave += new MouseEventHandler(ColumnHeader_MouseLeave);
            }
            SetAutomappingOnOff = false;
        }
        else if (e.Action == CollectionChangeAction.Remove)
        {
            DataColumn column = e.Element as DataColumn;
            DataGridColumn toRemove = (from DataGridColumn dc in this.Columns
                                       where dc.Header != null && dc.Header.ToString() == column.ColumnName
                                       select dc).First();
            this.Columns.Remove(toRemove);
            SetAutomappingOnOff = false;
        }
    }

DataGridHelper

public static class DataGridHelper 
{ 
    public static DataGridColumnHeader GetColumnHeader(DataGrid dataGrid, int index) 
    { 
        DataGridColumnHeadersPresenter presenter = FindVisualChild<DataGridColumnHeadersPresenter>(dataGrid); 
        if (presenter != null) { 
             return (DataGridColumnHeader)presenter.ItemContainerGenerator.ContainerFromIndex(index)‌​; 
        } 
        return null; 
    }
}

---

公共静态类DataGridHelper
{ 
公共静态DataGridColumnHeader GetColumnHeader（DataGrid DataGrid，int index）
{ 
DataGridColumnHeadersPresenter-presenter=FindVisualChild（dataGrid）；
如果（演示者！=null）{
return（DataGridColumnHeader）presenter.ItemContainerGenerator.ContainerFromIndex（索引）‌​; 
} 
返回null；
}
}

但columnHeader总是返回null，即使我可以看到对象被创建并添加到datagrid

    private void Columns_CollectionChanged(object sender, System.ComponentModel.CollectionChangeEventArgs e)
     {
        if (e.Action == CollectionChangeAction.Add)
        {
            int columnPosition = (this.Columns.Count - 1);
            DataGridTextColumn column = new DataGridTextColumn();
            column.Header = (e.Element as DataColumn).ColumnName;
            column.Binding = new Binding(string.Format("[{0}]", column.Header.ToString()));
            this.Columns.Insert(columnPosition, column);

            DataGridColumnHeader columnHeader = DataGridHelper.GetColumnHeader(this, columnPosition);
            if (columnHeader != null)
            {
                columnHeader.MouseEnter += new MouseEventHandler(ColumnHeader_MouseEnter);
                columnHeader.MouseLeave += new MouseEventHandler(ColumnHeader_MouseLeave);
            }
            SetAutomappingOnOff = false;
        }
        else if (e.Action == CollectionChangeAction.Remove)
        {
            DataColumn column = e.Element as DataColumn;
            DataGridColumn toRemove = (from DataGridColumn dc in this.Columns
                                       where dc.Header != null && dc.Header.ToString() == column.ColumnName
                                       select dc).First();
            this.Columns.Remove(toRemove);
            SetAutomappingOnOff = false;
        }
    }

请帮帮我

谢谢

---

Dee

列已添加到数据网格，但尚未添加到VisualTree，因此FindVisualChild方法返回null。我没有为列添加单击处理程序的好解决方案，但您可以将其添加到DataGrid，并检查发送方以查看在何处应用单击处理逻辑。

我建议在

DataGrid

-s

加载的
事件上注册
CollectionChanged
事件。这样，您可以确保将
DataGridColumnHeader
添加到可视化树中。它将如下所示：

myDataGrid.Loaded += (s,e) => {
    myCollection.CollectionChanged += (se, ev) => {
        //do work here
    };
};

什么是DataGridHelper及其如何获取列标题？公共静态类DataGridHelper{public static DataGridColumnHeader GetColumnHeader（DataGrid DataGrid，int index）{DataGridColumnHeadersPresenter presenter=FindVisualChild（DataGrid）；if（presenter！=null）{return（DataGridColumnHeader）presenter.ItemContainerGenerator.ContainerFromIndex（index）；}return null；}}