Question

我尝试将已定义的集合TheCollection与xaml定义的集合GreekHeroesData

组合在一起

ToCollectionWindow.xaml.vb：

Public Class ToCollectionWindow
    Public myCollection As New ObservableCollection(Of Person)

    Public ReadOnly Property TheCollection As ObservableCollection(Of Person)
        Get
            Return myCollection
        End Get
    End Property

    Private Sub InitYo(sender As Object, e As EventArgs)
        myCollection.Add(New Person("one"))
        myCollection.Add(New Person("two"))
        myCollection.Add(New Person("three"))
    End Sub
End Class

ToCollectionWindow.xaml

<Window ...
    DataContext="{Binding RelativeSource={RelativeSource Self}}" />
<XmlDataProvider x:Key="GreekHeroesData" XPath="GreekHeroes/Hero">
    <x:XData>
        <GreekHeroes xmlns="">
            <Hero Name="Jason" />
            <Hero Name="Hercules" />
            <Hero Name="Bellerophon" />
            <Hero Name="Theseus" />
            <Hero Name="Odysseus" />
            <Hero Name="Perseus" />
        </GreekHeroes>
    </x:XData>
</XmlDataProvider>
...

这是我尝试的内容：

<DataTemplate DataType="{x:Type TheCollection}">
    <TextBlock Foreground="Gold" Text="{Binding Path=Name}" />
</DataTemplate>
<DataTemplate DataType="Hero">
    <TextBlock Foreground="Cyan" Text="{Binding XPath=@Name}" />
</DataTemplate>

<ListBox Width="200" IsSynchronizedWithCurrentItem="True">
    <ListBox.ItemsSource>
        <CompositeCollection>
            <CollectionContainer Collection="{Binding TheCollection}" />
            <CollectionContainer Collection="{Binding Source={StaticResource GreekHeroesData}}" />
            <ListBoxItem Foreground="Red">Other Listbox Item 1</ListBoxItem>
            <ListBoxItem Foreground="Red">Other Listbox Item 2</ListBoxItem>
        </CompositeCollection>
    </ListBox.ItemsSource>
</ListBox>

构建失败： The type reference cannot find a public type named 'TheCollection'.

Answer 1

TheCollection包含Person个对象。因此，DataType的{{1}}应设置为DataTemplate，即它将应用于Person中的所有对象：

TheCollection

Answer 2

正如我在评论中所写，您必须为DataTemplate中的类型指定XAML名称空间。在你的情况下，它是ObservableCollection(Of Person)。真正的问题是，您无法在XAML中为ObservableCollection指定通用类型。
所以你必须做一个解决方法（抱歉VB语法，我用C＃开发）：

namespace YourViewModelNameSpace
{
    using System.Collections.ObjectModel;
    public class NonGenericPersonCollection : ObservableCollection<Person> { }
    //Public Class NonGenericPersonCollection Inherits ObservableCollection(Of Person)
}
Public ReadOnly Property TheCollection As NonGenericPersonCollection

<Window ...
xmlns:vm="clr-namespace:YourViewModelNameSpace" />
<DataTemplate DataType="{x:Type vm:NonGenericPersonCollection}">

WPF - 如何在Window的代码隐藏中访问公共字段的类型

2 个答案: