CompositeCollection + CollectionContainer：将CollectionContainer.Collection绑定到用作DataTemplates的ViewModel的属性DataType

问题描述

我没有获得正确的Binding语法来访问 Cats 和 Dogs 属性 DateTemplate 内的MyViewModel 在资源中定义了一个 CompositeCollection 。

I do not get the correct Binding syntax to access the Cats and Dogs properties of MyViewModel within a DateTemplate that defines a CompositeCollection within its resources.

public class MyViewModel
{
    public ObservableCollection<Cat> Cats { get; private set; }
    public ObservableCollection<Dog> Dogs { get; private set; }
}

<DataTemplate DataType={x:Type local:MyViewModel}">
  <DataTemplate.Resources>
    <CompositeCollection x:Key="MyColl">
      <!-- How can I reference the Cats and Dogs properties of MyViewModel? -->
      <CollectionContainer Collection="{Binding Dogs, ????}">
      <CollectionContainer Collection="{Binding Cats, ????}">
    </CompositeCollection>
  </DataTemplate.Resources>
  <ListBox ItemsSource="{StaticResource MyColl}">
    <!-- ... -->
  </ListBox>
</DataTemplate>

我必须插入????才能绑定 Dogs 和 Cats 集合到 CollectionContainer s？

What do I have to insert for ???? to bind the Dogs and Cats collections to the CollectionContainers?

推荐答案

对于 CollectionContainer 中的数据绑定的问题，如上所述我现在使用以下方法：

Due to the issue with data binding on CollectionContainer as described http://social.msdn.microsoft.com/Forums/vstudio/en-US/b15cbd9d-95aa-47c6-8068-7ae9f7dca88a/collectioncontainer-does-not-support-relativesource?forum=wpf I now use the following approach:

<ListBox>
  <ListBox.Resources>
    <CollectionViewSource x:Key="DogCollection" Source="{Binding Dogs}"/>
    <CollectionViewSource x:Key="CatCollection" Source="{Binding Cats}"/>
  </ListBox.Resources>
  <ListBox.ItemsSource>
    <CompositeCollection>
      <CollectionContainer Collection="{Binding Source={StaticResource DogCollection}}"/>
      <CollectionContainer Collection="{Binding Source={StaticResource CatCollection}}"/>
    </CompositeCollection>
  </ListBox.ItemsSource>
  <!-- ... -->
</ListBox>

编辑： CompositeCollection class不派生自 FrameworkElement ，因此没有一个 DataContext 属性来支持数据绑定。如果您使用绑定提供源，则它将工作。有关详细信息，请查看。

The CompositeCollection class does not derive from FrameworkElement and thus does not have a DataContext property to support data binding. It will only work if you use Binding providing a Source. Have a look here http://stackoverflow.com/a/6446923/1254795 for more information.

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