从列标题XAML中删除右键单击上下文菜单 [英] Remove right click context menu from column headers XAML

问题描述

在我的程序中，我有一个绑定到可观察列表的数据网格。我希望能够将上下文菜单设置为仅在选择行时显示，以便在没有选择任何内容时不会出现错误。为此，我希望能够禁用列标题上的上下文菜单。这是XAML：

In my program I have a datagrid which is bound to an observable list. I want to be able to set the context menu to only display when a row is selected so that there wont be errors with nothing being selected. To do this I would like to be able to disable the context menu on the column headers. Here is the XAML:

<DataGrid Name="dgItems" AutoGenerateColumns="False" SelectionMode="Single" SelectionUnit="FullRow" CanUserAddRows="False" IsReadOnly="True">
  <DataGrid.ContextMenu>
      <ContextMenu>
          <MenuItem Header="Edit Item" Click="EditItem_Click"/>
          <MenuItem Header="Delete Item" Click="DeleteItem_Click"/>
      </ContextMenu>
  </DataGrid.ContextMenu>
   <DataGrid.Columns>
      <DataGridTextColumn Header="Caption" Binding="{Binding Caption}"/>
      <DataGridTextColumn Header="Details" Binding="{Binding Details}"/>
      <DataGridTextColumn Header="DateFrom" Binding="{Binding DateFrom}"/>
      <DataGridTextColumn Header="DateTo" Binding="{Binding DateTo}"/>
      <DataGridTextColumn Header="Source" Binding="{Binding Source}"/>
   </DataGrid.Columns>
</DataGrid>

如何禁用标题上的上下文菜单？谢谢。

How would I go about disabling the context menus on the headers? Thanks.

推荐答案

在DataGrid的 PreviewMouseRightButtonDown 事件中使用此代码，

Use this code in PreviewMouseRightButtonDown event of DataGrid,

private void DataGrid_PreviewMouseRightButtonDown(object sender, MouseButtonEventArgs e)
{
    DependencyObject DepObject = (DependencyObject)e.OriginalSource;

    while ((DepObject != null) && !(DepObject is DataGridColumnHeader))
    {
        DepObject = VisualTreeHelper.GetParent(DepObject);
    }

    if (DepObject == null)
    {
        return;
    }

    if (DepObject is DataGridColumnHeader)
    {
          dgItems.ContextMenu.Visibility = Visibility.Collapsed;
    }
    else
    {
          dgItems.ContextMenu.Visibility = Visibility.Visible;
    }
}

上面提出的解决方案不起作用（或者对我来说无效）因为你需要测试DataGridRow，否则如果实际右键单击有效行，则总是为null。以下是对我有效的方法：

The proposed solution above does not work (or did not work for me anyway) as you need to test for DataGridRow as well, otherwise you always get null if you are actually right-clicking on a valid row. Here is what worked correctly for me:

        private void dgMP_MOCParts_PreviewMouseRightButtonDown(object sender, MouseButtonEventArgs e)
        {
            DependencyObject DepObject = (DependencyObject)e.OriginalSource;

            while ((DepObject != null) && !(DepObject is DataGridColumnHeader) 
&& !(DepObject is DataGridRow))
            {
                DepObject = VisualTreeHelper.GetParent(DepObject);
            }

            if (DepObject == null)
            {
                return;
            }

            if (DepObject is DataGridColumnHeader)
            {
                dgMP_MOCParts.ContextMenu.Visibility = Visibility.Collapsed;
            }
            else
            {
                dgMP_MOCParts.ContextMenu.Visibility = Visibility.Visible;
            }
        }

这篇关于从列标题XAML中删除右键单击上下文菜单的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！