Wpf TreeView IsExpanded - wpf

Question

I tried to bind to IsExpanded property in Hierarchical template with another context.
<HierarchicalDataTemplate x:Key="TreeView1" ItemsSource="{Binding Path=Folders}" >
<StackPanel Margin="5,5,5,5" Orientation="Horizontal">
<StackPanel Name="spinCont">
<ModulesUpToDateChecker1:Spinner Width="20" x:Name="Spin" FolderContext="{Binding}" StateContext="{Binding Path=State}"></ModulesUpToDateChecker1:Spinner>
<Image x:Name="imgFolderIcon" Width="16" Visibility="Hidden"
Source="/ModulesUpToDateChecker;component/Resources/FolderClosed16.png">
<Image.Triggers>
</Image.Triggers>
</Image>
<Image VerticalAlignment="Center" x:Name="imgFolderItem"
Source="{Binding Path=State, Converter={StaticResource stateFolderConverter}}">
<Image.Style>
<Style TargetType="{x:Type Image}">
<Style.Triggers>
<MultiDataTrigger>
<MultiDataTrigger.Conditions>
<Condition Binding="{Binding Path=IsLast}" Value="true"></Condition>
</MultiDataTrigger.Conditions>
<Setter Property="Visibility" Value="Collapsed"></Setter>
</MultiDataTrigger>
</Style.Triggers>
</Style>
</Image.Style>
</Image>
</StackPanel>
<StackPanel DataContext="{Binding Path=Modules}">
<ModulesUpToDateChecker1:Spinner Width="20">
<ModulesUpToDateChecker1:Spinner.Style>
<Style TargetType="{x:Type ModulesUpToDateChecker1:Spinner}">
<Setter Property="Visibility" Value="Collapsed" />
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Animation}" Value="True" >
<Setter Property="Visibility" Value="Visible" />
</DataTrigger>
</Style.Triggers>
</Style>
</ModulesUpToDateChecker1:Spinner.Style>
</ModulesUpToDateChecker1:Spinner>
<Image VerticalAlignment="Center"
Source="{Binding Path=State, Converter={StaticResource stateImageConverter}}">
<Image.Style>
<Style TargetType="{x:Type Image}">
<Style.Triggers>
<DataTrigger Binding="{Binding Path=Animation}" Value="True" >
<Setter Property="Visibility" Value="Collapsed" />
</DataTrigger>
</Style.Triggers>
</Style>
</Image.Style>
</Image>
</StackPanel>
<TextBlock Text="{Binding Path=Name}" Margin="10,0,0,0"></TextBlock>
</StackPanel>
<HierarchicalDataTemplate.Triggers>
<!--<Trigger Property="{Binding}" Value="true">
<Setter TargetName="imgFolderIcon" Property="Source" Value="/ModulesUpToDateChecker;component/Resources/Error.png" />
</Trigger>-->
**<DataTrigger Binding="{Binding Path=IsExpanded}" Value="true">
<Setter TargetName="imgFolderIcon" Property="Source" Value="/ModulesUpToDateChecker;component/Resources/Error.png" />
</DataTrigger>**
doest work
</HierarchicalDataTemplate.Triggers>
</HierarchicalDataTemplate>
I have the "Folder" context (its hierarchical object) but how can i bind to theTreeView properties in HierarchicalDataTemplate.Triggers? When i start this, output shows that there is no IsExpanded property in Folder object. So, i have wrong context.

Answer 1

<DataTrigger Binding="{Binding RelativeSource={RelativeSource AncestorType=TreeViewItem}, Path=IsExpanded}" Value="true">
<Setter TargetName="imgFolderIcon" Property="Source" Value="/Resources/FolderExpanded.png" />
</DataTrigger>
Easy