带有扩展器的ScrollViewer

Question

I have a ScrollViewer in my Silverlight project which contains expanders with content. The VerticalScrollBarVisibility is set to Auto and HorizontalScrollBarVisibility set to Disabled as it is not needed. The problem is when I expand one or more expanders so that the Vertical scrollbar is visible, it pushes the content within the expander slightly to the left. How can I make it so when the (Vertical) scrollbar appears that it doesn't push expanders/content to the left?

I cannot upload images so uploaded expanded example to TinyPic:

http://i42.tinypic.com/xvamd.png

Sample code available at http://pastebin.com/khPR8nPF

Thanks!

Answer 1

You could do something like:

<ScrollViewer Name="scrollViewer1"
              Grid.Row="1"
              Grid.ColumnSpan="2"
              VerticalAlignment="Stretch"
              VerticalContentAlignment="Stretch"
              BorderBrush="{x:Null}"
              VerticalScrollBarVisibility="Auto">
  <!-- New Bit -->
  <ScrollViewer.Style>
    <Style TargetType="{x:Type ScrollViewer}">
      <Style.Resources>
        <Thickness x:Key="InvisScrollBarDimension"
                    Bottom="0"
                    Left="0"
                    Right="{StaticResource {x:Static SystemParameters.VerticalScrollBarWidthKey}}"
                    Top="0" />
      </Style.Resources>
      <Setter Property="Margin"
              Value="{StaticResource InvisScrollBarDimension}" />
      <Style.Triggers>
        <Trigger Property="ComputedVerticalScrollBarVisibility"
                  Value="Visible">
          <Setter Property="Margin"
                  Value="0" />
        </Trigger>
      </Style.Triggers>
    </Style>
  </ScrollViewer.Style>
  ...

Concept is pretty much give the ScrollViewer a right Margin based on System parameter VerticalScrollBarWidthKey when the Scrollbar is not visible which the Trigger for ComputedVerticalScrollBarVisibility helps us determine and reset it to 0 when Scrollbar is visible.

This should give the no jitter effect at run-time.