从 DataTemplate 中的 DataTemplate 中引用 ViewModel 的 DataContext [英] Reference ViewModel's DataContext from within a DataTemplate in a DataTemplate

问题描述

我发现自己有点束手无策...绑定...呵呵...(跛脚)

I found myself in a bit of a bind... with bindings... hehe... (lame)

无论如何...我需要参考主 ViewModel 的属性，但是在 DataTemplate 中，它本身在另一个 DataTemplate 中...它看起来像Silverlight 允许的唯一 RelativeSource 模式是:Self 和 TemplatedParent.并且 TemplatedParent 上升得不够.

Anyway... I need to refer to the main ViewModel's Property, but from within a DataTemplate, which is itself within another DataTemplate... and it looks like the only RelativeSource mode that Silverlight allows are: Self and TemplatedParent. And TemplatedParent doesn't go up enough.

有什么可以做的吗?

一些代码:

<phone:PanoramaItem>
    <phone:LongListSelector Margin="0,-38,-22,2" ItemsSource="{Binding Items}">
        <phone:LongListSelector.ItemTemplate>
            <DataTemplate>
                <common:ItemContentTemplateSelector DataContext="{Binding}" Content="{Binding ItemContent}" HorizontalContentAlignment="Stretch" Margin="12,2,0,4">
                    <common:ItemContentTemplateSelector.DefaultTemplate>
                        <DataTemplate>
                            .....
                        </DataTemplate>
                    </common:ItemContentTemplateSelector.DefaultTemplate>
                    <common:ItemContentTemplateSelector.PhoneNumberTemplate>
                        <DataTemplate>
                            <Grid Background="White" Height="102">
                                <Border x:Name="border">
                                    <TextBlock Text="Call"/>
                                    <i:Interaction.Triggers>
                                        <i:EventTrigger EventName="MouseLeftButtonDown">
                                     <!-- BINDING ERROR -->
                                            <i:InvokeCommandAction Command="{Binding RelativeSource={RelativeSource Mode=TemplatedParent}, Path=DataContext.PhoneCallCommand}"/>
                                        </i:EventTrigger>
                                    </i:Interaction.Triggers>
                                </Border>
                            </Grid>
                        </DataTemplate>
                    </common:ItemContentTemplateSelector.PhoneNumberTemplate>
                </common:ItemContentTemplateSelector>
            </DataTemplate>
        </phone:LongListSelector.ItemTemplate>
    </phone:LongListSelector>
</phone:PanoramaItem>

推荐答案

如果您没有解决方法或无法轻松解决，有事要做；

If you don't wont a workaround or make it easily, There is something to do;

使用静态资源

看看这个;

   MyViewModelClass ViewModel
   {
        get;set;
   }

  ...ctor()
  {
     this.ViewModel=new MyViewModelClass();
     this.DataContext=this.ViewModel; //We use same VM instance as DataContext as Resource
     this.Resoureces.Add("MainVieModel",ViewModel);
     InitializeComponents();//...Add resource before this line
  }

之后你可以在任何你想要的地方同时使用你的ViewModel作为StaticResource；

After that you can use your ViewModel at the same time as a StaticResource anywhere you want;

{Binding Path=Items,Source={StaticResource ViewModel}}

我在 stackoverflow 的编辑器上编码.可能缺少一些字符...

I coded on stackoverflow's editor. There could be some missing chars ...

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