TreeViewItem Tooltip Binding Not Working - wpf

Question

I have a treeview. It's bound to an ObservableCollection called Nodes. The bound data on the tool tips is not showing:
<controls:TreeViewEx BorderThickness="0"
ItemsSource="{Binding Nodes}"
SelectedItemEx="{Binding SelectedTreeNode, Mode=TwoWay}">
<controls:TreeViewEx.ToolTip>
<Grid>
<Grid.RowDefinitions>
<RowDefinition Height="Auto"/>
<RowDefinition Height="Auto"/>
<RowDefinition Height="*"/>
</Grid.RowDefinitions>
<Grid.ColumnDefinitions>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="Auto"/>
<ColumnDefinition Width="*"/>
</Grid.ColumnDefinitions>
<Image Grid.Row="0"
Grid.Column="0"
Source="/FMG.UI.WPF;component/Media/Images/job_128.png"
Height="16"
Width="16"/>
<TextBox Grid.Row="0"
Grid.Column="1"
Text="Job: "
FontWeight="Bold"/>
<TextBox Grid.Row="0"
Grid.Column="2"
Text="{Binding ToolTipHeader}"/>
<Border Grid.Row="1"
Grid.Column="0"
Grid.ColumnSpan="3"
Height="2"
BorderBrush="Gray"/>
<TextBox Grid.Row="2"
Grid.Column="0"
Grid.ColumnSpan="3"
Text="{Binding ToolTipDetails}"/>
</Grid>
</controls:TreeViewEx.ToolTip>
</controls:TreeViewEx>
The tooltip pops up, but the ToolTipHeader and and ToolTipDetails are blank. The Output window says it can't find them on the view model. How do I make the binding look on the Node, not the view model?

Answer 1

You probably want to move the code; use the TreeView.ItemContainerStyle and add a Setter for the ToolTip, this will set a node-level tool-tip.
e.g.
<controls:TreeViewEx.ItemContainerStyle>
<Style TargetType="controls:TreeViewItemEx"> <!-- Guessing at item type name here -->
<Setter Property="Tooltip">
<Setter.Value>
<!-- Move your tooltip here -->
</Setter.Value>
</Setter>
</Style>
</controls:TreeViewEx.ItemContainerStyle>
Of course the DataContext for all the bindings in the tooltip will be the current item, if you want the context of the tree-view specify a RelativeSource that finds it (also prepend "DataContext" on the Path, otherwise you bind to properties directly on the tree-view).