Possible Duplicate:
Change selected and unfocused Listbox style to not be grayed out
I'd only like to keep the blue focus on the treeview and disable the grey focus. How can this be done in WPF?
In order to achieve that, you need to replace the System Control Brush like following in TreeViewItem's resources:
<Style TargetType="TreeViewItem" x:Key="TreeViewItemStyle">
<Style.Resources>
<SolidColorBrush x:Key="{x:Static SystemColors.ControlBrushKey}" Color="Blue>"/>
</Style.Resources>
</Style>