About style of MulticolumnTreeView

Hi. I want to ask a question about MulticolumnTreeView. My code is like this:

      <ms:MulticolumnTreeView  Margin="0,0,0,0" Name="RunParamTree" ItemsSource="{Binding RunParams}" AllowsColumnReorder="True" BorderBrush="{x:Null}">
        <ms:MulticolumnTreeView.Resources>
            <ResourceDictionary>
                <Style TargetType="ms:MulticolumnTreeViewItem">
                   <Setter  Property="IsExpanded" Value="{Binding IfIsExpanded, Converter={StaticResource CheckBoxValueConverter},Mode=TwoWay}"></Setter>
                </Style>
                <ResourceDictionary.MergedDictionaries>
                    <ms:OfficeBlue />
                </ResourceDictionary.MergedDictionaries>
            </ResourceDictionary>
        </ms:MulticolumnTreeView.Resources>
        <ms:MulticolumnTreeView.ItemTemplate>
            <HierarchicalDataTemplate ItemsSource="{Binding ChildParams}" />
        </ms:MulticolumnTreeView.ItemTemplate>

I want to save the TreeViewItem information of IfIsExpanded,so I set the Property of IsExpanded and it works in function.But it change the style of MulticolumnTreeViewItem. After adding these code,I can't select a row of MulticolumnTreeView and some styles of ms:OfficeBlue disappear. how to slove it?

Hello

The OfficeBlue styles are disappearing because the style you've added to the resource dictionary is overriding the OfficeBlue style. This can be resolved by setting the BasedOn property of the style like this:

<Style TargetType="ms:MulticolumnTreeViewItem" BasedOn="{StaticResource {x:Type ms:MulticolumnTreeViewItem}}">
  . . .
</Style>

This makes your style extend the existing style, which in your case will be the OfficeBlue style. Note that for some reason this does not work when you set OfficeBlue in the merged dictionary of the MulticolumnTreeView like what you're doing here. Instead you will need to set OfficeBlue in a merged dictionary of either the Window of the application, or a panel containing the MulticolumnTreeView.

Let me know if you run into any trouble.

-Jason

Thx very much,Jason.