It does not work off MenuItem in ContextMenu

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WPF

It does not work off MenuItem in ContextMenu.

Bind it to the ListView. If an element in ListVIew not selected, IsEnabled a MenuItem should be able to false.

<Window.Resources>
     <ContextMenu x:Key="CategoryiesTaskMenu">
         <MenuItem Header="Add Category"/>
            <MenuItem Header="Edit Category">
                 <MenuItem.Style>
                    <Style TargetType="{x:Type MenuItem}">
                        <Style.Triggers>
                            <DataTrigger Binding="{Binding ElementName=listView, Path=SelectedIndex}" Value="-1">
                                <Setter Property="IsEnabled" Value="False"/>
                            </DataTrigger>
                        </Style.Triggers>
                    </Style>
                </MenuItem.Style>
            </MenuItem>
      </ContextMenu>
</Window.Resources>

<ListView Name="listViewTask" ContextMenu="{DynamicResource CategoryiesTaskMenu}">