我有一个 wpf 树视图,它显示各种类型的节点以及相应的图像,例如文件夹图像。最初,树及其具有相应图像的节点按预期显示。然而,当一个节点被扩展时,期望的是扩展节点的图像应该交换为扩展图像。我正在尝试使用HierarchicalDataTemplate
触发器来设置它。
触发器是否应该设置不同?
这棵树看起来像:
(Folder Image) Solutions (SolutionsViewModel)
--(Solution Image) Solution 1 (Solution)
--(Solution Image) Solution 2 (Solution)
(Folder Image) Conventions (ConventionsViewModel)
树视图中主要节点的xaml(主题为空):
<UserControl.Resources>
<ResourceDictionary>
<ResourceDictionary.MergedDictionaries>
<ResourceDictionary Source="../Theme.xaml" />
</ResourceDictionary.MergedDictionaries>
<HierarchicalDataTemplate DataType="{x:Type vm:SolutionsViewModel}" ItemsSource="{Binding Items}">
<StackPanel Orientation="Horizontal">
<Image x:Name="nodeImg" Width="16" Height="16" Source="pack://siteOfOrigin:,,,/Resources/FolderClosed.bmp"/>
<TextBlock Margin="5,0,0,0" Text="{Binding Name}" />
</StackPanel>
<HierarchicalDataTemplate.Triggers>
<DataTrigger Binding="{Binding IsExpanded}" Value="True">
<Setter TargetName="nodeImg" Property="Source" Value="pack://siteOfOrigin:,,,/Resources//FolderOpen.bmp"/>
</DataTrigger>
</HierarchicalDataTemplate.Triggers>
</HierarchicalDataTemplate>
<HierarchicalDataTemplate DataType="{x:Type sol:Solution}" ItemsSource="{Binding Items}">
<StackPanel Orientation="Horizontal">
<Image x:Name="treeImg" Width="16" Height="16" Source="pack://siteOfOrigin:,,,/Resources/SolutionClosed.bmp"/>
<TextBlock Margin="5,0,0,0" Text="{Binding Name}" />
</StackPanel>
<HierarchicalDataTemplate.Triggers>
<DataTrigger Binding="{Binding IsExpanded}" Value="True">
<Setter TargetName="treeImg" Property="Source" Value="pack://siteOfOrigin:,,,/Resources//SolutionOpen.bmp"/>
</DataTrigger>
</HierarchicalDataTemplate.Triggers>
</HierarchicalDataTemplate>
<HierarchicalDataTemplate DataType="{x:Type vm:ConventionsViewModel}" ItemsSource="{Binding Items}">
<StackPanel Orientation="Horizontal">
<Image x:Name="nodeImg" Width="16" Height="16" Source="pack://siteOfOrigin:,,,/Resources/FolderClosed.bmp"/>
<TextBlock Margin="5,0,0,0" Text="{Binding Name}" />
</StackPanel>
<HierarchicalDataTemplate.Triggers>
<DataTrigger Binding="{Binding IsExpanded}" Value="True">
<Setter TargetName="nodeImg" Property="Source" Value="pack://siteOfOrigin:,,,/Resources//FolderOpen.bmp"/>
</DataTrigger>
</HierarchicalDataTemplate.Triggers>
</HierarchicalDataTemplate>
</ResourceDictionary>
</UserControl.Resources>
<UserControl.DataContext>
<ObjectDataProvider
ObjectType="{x:Type vm:TreeViewModel}"
MethodName="CreateDefaultTree"
/>
</UserControl.DataContext>
<ScrollViewer VerticalScrollBarVisibility="Auto" HorizontalScrollBarVisibility="Auto">
<Grid>
<TreeView Name="solutionsModel" ItemsSource="{Binding Items}">
<TreeView.ItemContainerStyle>
<Style TargetType="{x:Type TreeViewItem}">
<Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay}" />
<Setter Property="IsSelected" Value="{Binding IsSelected, Mode=TwoWay}" />
<Setter Property="FontWeight" Value="Normal" />
<Style.Triggers>
<Trigger Property="IsSelected" Value="True">
<Setter Property="FontWeight" Value="Bold" />
</Trigger>
</Style.Triggers>
</Style>
</TreeView.ItemContainerStyle>
</TreeView>
</Grid>
</ScrollViewer>