Question

我有很多ListView，每个都绑定到自己的ListCollectionView，每个都有相同的ContextMenu需求。我不想重复相同的ContextMenu N次，所以我在参考资料中定义它并通过StaticResource引用它。

当右键单击ListView中的项目X并单击MenuItem时，如何在代码隐藏中访问对象X？

<Window.Resources>
    <ContextMenu x:Key="CommonContextMenu">
        <MenuItem Header="Do Stuff" Click="DoStuff_Click" />
    </ContextMenu>
</Window.Resources>

<ListView ItemsSource="{Binding Path=ListCollectionView1}" ContextMenu="{StaticResource CommonContextMenu}">
    ...
</ListView>

<ListView ItemsSource="{Binding Path=ListCollectionView2}" ContextMenu="{StaticResource CommonContextMenu}">
    ...
</ListView>

private void DoStuff_Click(object sender, RoutedEventArgs e)
{
    // how do i get the selected item of the right listview?
}

更新

感谢Michael Gunter的回答，我现在使用以下扩展方法：

public static ListView GetListView(this MenuItem menuItem)
{
    if (menuItem == null)
        return null;

    var contextMenu = menuItem.Parent as ContextMenu;
    if (contextMenu == null)
        return null;

    var listViewItem = contextMenu.PlacementTarget as ListViewItem;
    if (listViewItem == null)
        return null;

    return listViewItem.GetListView();
}

public static ListView GetListView(this ListViewItem item)
{
    for (DependencyObject i = item; i != null; i = VisualTreeHelper.GetParent(i))
    {
        var listView = i as ListView;
        if (listView != null)
            return listView;
    }

    return null;
}

Answer 1

1）将上下文菜单放在每个ListView内的每个项目上，而不是放在每个ListView本身上。这样可以避免在单击ListView中的空白区域时弹出上下文菜单。为此，请使用ListView.ItemContainerStyle属性。（如果你真的想要ListView本身的上下文菜单，请告诉我，我会相应地编辑这个答案。）

<Window.Resources>
    <ContextMenu x:Key="CommonContextMenu">
        <MenuItem Header="Do Stuff" Click="DoStuff_Click" />
    </ContextMenu>
    <Style x:Key="ListViewItemStyle" TargetType="{x:Type ListViewItem}">
        <Setter Property="ContextMenu" Value="{StaticResource CommonContextMenu}" />
    </Style>
</Window.Resources>

<ListView ItemsSource="{Binding Path=ListCollectionView1}" ItemContainerStyle="{StaticResource ListViewItemStyle}">
    ...
</ListView>
<ListView ItemsSource="{Binding Path=ListCollectionView2}" ItemContainerStyle="{StaticResource ListViewItemStyle}">
    ...
</ListView>

2）使用以下代码确定右键单击的项目。

private void DoStuff_Click(object sender, RoutedEventArgs e)
{
    var menuItem = sender as MenuItem;
    if (menuItem == null)
        return;

    var contextMenu = menuItem.Parent as ContextMenu;
    if (contextMenu == null)
        return;

    var listViewItem = contextMenu.PlacementTarget as ListViewItem;
    if (listViewItem == null)
        return;

    var listView = GetListView(listViewItem);
    if (listView == null)
        return;

    // do stuff here
}

private ListView GetListView(ListViewItem item)
{
    for (DependencyObject i = item; i != null; i = VisualTreeHelper.GetParent(i))
    {
        var listView = i as ListView;
        if (listView != null)
            return listView;
    }
    return null;
}

多个ListView共享一个ContextMenu，我该如何引用正确的对象？

1 个答案: