wpf - can't display TreeView items
I have the following code which supposed to display a TreeView (the original code is more complicated, thus the complex control hirerchy):
<TreeView ItemsSource="{Binding TreeRoot}"
HorizontalAlignment="Left">
<TreeView.Resources>
<DataTemplate x:Key="CTemplate">
<Border >
<Grid>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="*"/>
<ColumnDefinition Width="auto"/>
</Grid.ColumnDefinitions>
<ToggleButton
Grid.Column="1"
x:Name="Expander"
HorizontalAlignment="Right"
ClickMode="Press"/>
<TextBlock Text="{Binding Name}"
Grid.Column="0" />
</Grid>
</Border>
<DataTemplate.Triggers>
<DataTrigger Binding="{Binding Path=HasItems, RelativeSource={RelativeSource AncestorType={x:Type TreeViewItem}}}" Value="False">
<Setter TargetName="Expander" Property="Visibility" Value="Hidden"/>
</DataTrigger>
</DataTemplate.Triggers>
</DataTemplate>
<Style TargetType="{x:Type TreeViewItem}" x:Key="aaa">
<Setter Property="ItemsSource" Value="{Binding Children}"/>
<Setter Property="IsExpanded" Value="{Binding Path=IsExpanded,Mode=TwoWay}"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
<StackPanel>
<Border Name="Bd"
Background="{TemplateBinding Background}">
</Border>
<ItemsPresenter x:Name="ItemsP" />
</StackPanel>
<ControlTemplate.Triggers>
<Trigger Property="IsExpanded" Value="false">
<Setter TargetName="ItemsP"
Property="Visibility"
Value="Collapsed"/>
</Trigger>
</ControlTemplate.Triggers>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
<Style TargetType="{x:Type TreeView}">
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeView}">
<Border BorderBrush="{TemplateBinding BorderBrush}"
BorderThickness="{TemplateBinding BorderThickness}">
<DockPanel>
<ItemsPresenter/>
</DockPanel>
</Border>
</ControlTemplate>
</Setter.Value>
</Setter>
<Setter Property="ItemContainerStyle" Value="{StaticResource aaa}" />
开发者_如何学C <Setter Property="ItemTemplate" Value="{CTemplate}" />
</Style>
</TreeView.Resources>
</TreeView>
Could you please help me figure out why my items are not displayed? (The page appears empty)
Thanks, Li
You don't have anything showing the Header of the TreeViewItem:
<Style TargetType="{x:Type TreeViewItem}" x:Key="aaa">
...
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="{x:Type TreeViewItem}">
<StackPanel>
<Border Name="Bd" Background="{TemplateBinding Background}">
<ContentPresenter x:Name="PART_Header"
ContentSource="Header"
HorizontalAlignment="{TemplateBinding HorizontalContentAlignment}"
SnapsToDevicePixels="{TemplateBinding SnapsToDevicePixels}"/>
</Border>
<ItemsPresenter x:Name="ItemsP" />
</StackPanel>
...
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
Above I added the ContentPresenter.
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