Silverlight TreeView Disable Horizontal Stretching - silverlight

Question

I have a TreeView and I'm attempting to confine it to the dimensions of its parent. I'm using SL4 TextTrimming to trim the TextBlock that displays in the template however I'm not seeing the width of the TreeView bound to that of the parent so the TextBlocks containing long text push out the width of the TreeView.
I've tried disabling the horizontal scroll bar, binding the Width to the parent, and fiddling with the HorizontalAlignment as well as HorizontalContentAlignment but I'm not having any luck. Any input is greatly appreciated.

Answer 1

the reason that disabling the horizontal scrollbar doesn't work is because in the default TreeView style, the scrollviwer's HorizontalScrollBarVisibility is set to Auto. What you can do is to create your own style and make it TemplateBinding to the parent.
<Style TargetType="sdk:TreeView">
<Setter Property="Background" Value="#FFFFFFFF"/>
<Setter Property="Foreground" Value="#FF000000"/>
<Setter Property="HorizontalContentAlignment" Value="Left"/>
<Setter Property="VerticalContentAlignment" Value="Top"/>
<Setter Property="Cursor" Value="Arrow"/>
<Setter Property="BorderThickness" Value="1"/>
<Setter Property="Padding" Value="1"/>
<Setter Property="BorderBrush" Value="#FF000000"/>
<Setter Property="IsTabStop" Value="True"/>
<Setter Property="TabNavigation" Value="Once"/>
<Setter Property="Template">
<Setter.Value>
<ControlTemplate TargetType="sdk:TreeView">
<Grid>
<VisualStateManager.VisualStateGroups>
<VisualStateGroup x:Name="CommonStates">
<VisualState x:Name="Normal"/>
<VisualState x:Name="MouseOver"/>
<VisualState x:Name="Pressed"/>
<VisualState x:Name="Disabled"/>
</VisualStateGroup>
<VisualStateGroup x:Name="FocusStates">
<VisualState x:Name="Unfocused"/>
<VisualState x:Name="Focused"/>
</VisualStateGroup>
<VisualStateGroup x:Name="ValidationStates">
<VisualState x:Name="Valid"/>
<VisualState x:Name="InvalidUnfocused">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="Validation">
<DiscreteObjectKeyFrame KeyTime="0" Value="Visible"/>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
<VisualState x:Name="InvalidFocused">
<Storyboard>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="Visibility" Storyboard.TargetName="Validation">
<DiscreteObjectKeyFrame KeyTime="0" Value="Visible"/>
</ObjectAnimationUsingKeyFrames>
<ObjectAnimationUsingKeyFrames Storyboard.TargetProperty="IsOpen" Storyboard.TargetName="ValidationToolTip">
<DiscreteObjectKeyFrame KeyTime="0">
<DiscreteObjectKeyFrame.Value>
<System:Boolean>True</System:Boolean>
</DiscreteObjectKeyFrame.Value>
</DiscreteObjectKeyFrame>
</ObjectAnimationUsingKeyFrames>
</Storyboard>
</VisualState>
</VisualStateGroup>
</VisualStateManager.VisualStateGroups>
<Border BorderBrush="{TemplateBinding BorderBrush}" BorderThickness="{TemplateBinding BorderThickness}" CornerRadius="2">
<Border Background="{TemplateBinding Background}" Margin="1" Padding="{TemplateBinding Padding}">
<ScrollViewer x:Name="ScrollViewer" BorderBrush="Transparent" BorderThickness="0" Background="{x:Null}" HorizontalScrollBarVisibility="{TemplateBinding ScrollViewer.HorizontalScrollBarVisibility}" IsTabStop="False" TabNavigation="Once" VerticalScrollBarVisibility="Auto">
<ItemsPresenter Margin="5"/>
</ScrollViewer>
</Border>
</Border>
<Border x:Name="Validation" BorderBrush="#FFDB000C" BorderThickness="{TemplateBinding BorderThickness}" Grid.Column="1" CornerRadius="2" Visibility="Collapsed">
<ToolTipService.ToolTip>
<ToolTip x:Name="ValidationToolTip" DataContext="{Binding RelativeSource={RelativeSource TemplatedParent}}" IsHitTestVisible="True" Placement="Right" PlacementTarget="{Binding RelativeSource={RelativeSource TemplatedParent}}" Template="{StaticResource CommonValidationToolTipTemplate}"/>
</ToolTipService.ToolTip>
<Grid Background="Transparent" HorizontalAlignment="Right" Height="10" Margin="0,-4,-4,0" VerticalAlignment="Top" Width="10">
<Path Data="M 1,0 L6,0 A 2,2 90 0 1 8,2 L8,7 Z" Fill="#FFDC000C" Margin="-1,3,0,0"/>
<Path Data="M 0,0 L2,0 L 8,6 L8,8" Fill="#FFFFFFFF" Margin="-1,3,0,0"/>
</Grid>
</Border>
</Grid>
</ControlTemplate>
</Setter.Value>
</Setter>
</Style>
After applying this style you should have a horizontal scrollbar disabled treeview. Then you need to set the max width of your textblock to allow the ellipsis to show.
Please let me know if this helps. :)