绑定到包含ItemControl数据的UserControl

Question

我创建了一个UserControl（MediaList），其中包含绑定到属性“ToolsBar”的ItemControl。这个想法是允许从MediaList控件外部添加自定义按钮/控件。

我的问题是，我试图将一个按钮添加到具有绑定到UserControl本身的ToolsBar。我不重写我的MediaList（UserControl）的DataContext为“this”，因为我需要使用在根窗口中定义的DataModel。

也许我这样做的方式是完全错误的？

这里是使用自定义按钮将medialist中的该窗口的为例：

<localControls:MediaList x:Name="NewMediaList"> 
       <localControls:MediaList.ToolsBar> 
        <Button Content="{StaticResource ResourceKey=MoveToPlaylist}" 
          IsEnabled="{Binding ElementName=NewMediaList, Path=SelectedMedia, Converter={localConverters:ObjectToBool}}"/> 
       </localControls:MediaList.ToolsBar> 
      </localControls:MediaList> 

直到现在我试图多个种如没有成功绑定：

• {结合的ElementName = MediaListControl，Path = SelectedMedia，Converter = {localConverters：ObjectToBool}}“
• {Binding RelativeSource = {x：Static RelativeSource.Self}，Path = SelectedMedia，Converter = {localConverters：Debug}}
• {结合SelectedMedia，的RelativeSource = {的RelativeSource FindAncestor，AncestorType = {X：类型用户控件}}}
• {结合SelectedMedia，的RelativeSource = {的RelativeSource FindAncestor，AncestorType = {X：类型localControls：medialist中}}}

注意我把它们从我的记忆中写回来，我也尝试过（并且没有）将MediaControl.xaml中的ItemControl和StackPanel（它包含ItemControm）的DataContext设置为MediaList对象本身。

MediaList.xaml：

<UserControl x:Class="MediaPlaylist.Controls.MediaList" 
     xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation" 
     xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml" 
     xmlns:mc="http://schemas.openxmlformats.org/markup-compatibility/2006" 
     xmlns:d="http://schemas.microsoft.com/expression/blend/2008" 
     xmlns:localConverters="clr-namespace:Suisse.MediaPlaylist.Converters" 
     mc:Ignorable="d" 
     d:DesignHeight="300" d:DesignWidth="300" 
     x:Name="MediaListControl"> 
<Grid> 
    <Grid.RowDefinitions> 
     <RowDefinition Height="*" /> 
     <RowDefinition Height="Auto"/> 
    </Grid.RowDefinitions> 

    <DataGrid Grid.Row="0" 
       AutoGenerateColumns="False" 
       ItemsSource="{Binding ElementName=MediaListControl, Path=Playlist.Medias}" 
       SelectedItem="{Binding ElementName=MediaListControl, Path=SelectedMedia, Mode=TwoWay}"> 
     <DataGrid.Columns> 
      <DataGridTextColumn Header="Title" 
           Binding="{Binding Title}" 
           IsReadOnly="True"/> 
      <DataGridTextColumn Header="File" 
           Binding="{Binding FilePath}" 
           IsReadOnly="True"/> 
     </DataGrid.Columns> 
    </DataGrid> 

    <StackPanel Orientation="Horizontal" 
       HorizontalAlignment="Right" 
       Grid.Row="1"> 
     <ItemsControl ItemsSource="{Binding ElementName=MediaListControl, Path=ToolsBar}"> 
      <ItemsControl.ItemsPanel> 
       <ItemsPanelTemplate> 
        <StackPanel Orientation="Horizontal" /> 
       </ItemsPanelTemplate> 
      </ItemsControl.ItemsPanel> 
     </ItemsControl> 
     <Separator Visibility="{Binding ElementName=MediaListControl, Path=ToolsBar.Count, Converter={localConverters:ObjectToVisibility}}" /> 
     <Button 
      HorizontalAlignment="Right" 
      Content="Delete" 
      Click="OnDelete_Click" 
      IsEnabled="{Binding ElementName=MediaListControl, Path=SelectedMedia, Converter={localConverters:ObjectToBool}}"/> 
    </StackPanel> 
</Grid> 

感谢

Answer 1

首先，您要指定绑定数据的ItemsControl的ItemsSource属性，这是完全错误的。 取而代之的是，你可以在你的MedialList.xaml.cs声明ItemsControl的依赖属性

 public partial class MediaList : UserControl 
    { 
     public MediaList() 
     { 
      InitializeComponent(); 

     } 

     public static DependencyProperty ToolsBarProperty = DependencyProperty. 
    Register("ToolsBar", typeof(ItemsControl), typeof(MediaList)); 

     public ItemsControl ToolsBar 
     { 
      get { return (ItemsControl)GetValue(ToolsBarProperty); } 
      set { SetValue(ToolsBarProperty, value); } 
     } 
    } 

然后，您可以更新medialist中的XAML为

<StackPanel Orientation="Horizontal" 
      HorizontalAlignment="Right" 
      Grid.Row="1"> 
     <ContentControl Content="{Binding ElementName=MediaListControl, Path=ToolsBar}"> 

     </ContentControl> 

然后你就可以从外部指派任何集合模板工具栏属性as

<localControls:MediaList> 
      <localControls:MediaList.ToolsBar> 
       <ItemsControl > 
        <ItemsControl.Items> 
         <Button Content="{StaticResource ResourceKey=MoveToPlaylist}" 
         IsEnabled="{Binding ElementName=NewMediaList, Path=SelectedMedia, Converter={localConverters:ObjectToBool}}"/> 
         <Label>Hello </Label> 
         <Label> How are you?</Label> 
        </ItemsControl.Items> 
        <ItemsControl.ItemsPanel> 
         <ItemsPanelTemplate> 
          <StackPanel Orientation="Horizontal" /> 
         </ItemsPanelTemplate> 
        </ItemsControl.ItemsPanel> 
       </ItemsControl> 
      </localControls:MediaList.ToolsBar> 
     </localControls:MediaList> 

希望这能解决您的问题。

注：我刚刚搬出了MediaList用户控件中定义的ItemsControl，并将其替换为ContentControl。这允许从外部设置ContentControl的Content属性的任何模板。