无法访问父级的数据上下文

本文介绍了无法访问父级的数据上下文的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

基本上我拥有的是带有ContextMenu的ListBox

Basically what i have is a ListBox with ContextMenu

<ListBox Margin="2,0,0,0" Grid.Row="1" ItemsSource="{Binding MyCollection}"> <ListBox.ItemTemplate> <DataTemplate> <Button Style="{StaticResource NoVisualButton }" Tag="{Binding ID}" Width="430" toolkit:TiltEffect.IsTiltEnabled="True" Margin="0,0,0,12" Click="OnSelectWorkOutItemClick"> <StackPanel> <toolkit:ContextMenuService.ContextMenu> <toolkit:ContextMenu> <toolkit:MenuItem Header="delete" Tag="{Binding ID}" Click="onContextMenuDeleteItemClick" IsEnabled="{Binding IsDeleteOptionEnable, ElementName=LayoutRoot}"/> <toolkit:MenuItem Header="edit" Tag="{Binding ID}" Click="onContextMenuItemEditClick" /> </toolkit:ContextMenu> </toolkit:ContextMenuService.ContextMenu> ... </StackPanel> </Button> </DataTemplate> </ListBox.ItemTemplate> </ListBox>

因此，如果MyCollection只有一项，则必须禁用delete MenuItem.

So if MyCollection has only one item, i have to disable delete MenuItem.

我的模型有一个属性

public bool IsDeleteOptionEnable { get { return MyCollection.Count() >= 2; } }

在页面中，我将DataContext设置为:

In the page i am setting the DataContext like:

protected override void OnNavigatedTo(NavigationEventArgs e) { if (IsDataLoaded) { this.DataContext =MyModel; } }

列表框正在填充，但是我不能禁用删除" MenuItem.我在做什么错了?

The listbox is getting populated, but i can't disable "delete" MenuItem. What am i doing wrong?

推荐答案

尝试

IsEnabled="{Binding DataContext.IsDeleteOptionEnable, ElementName=LayoutRoot}"