Expand/collapse on mouseEnter?

[Emilio]

Hello,

I'd like to be able to expand/collapse the TreeviewItems by simply mousing over.  I see that this was resolved in a web setting using javascript (http://www.telerik.com/forums/treeview-expand-on-hover), but is there a way to do this in WPF?

Thanks,

Emilio

[Emilio]

Oops, nevermind.  The solution was actually easier than I thought.

By setting an event handler for the TreeViewItemContainerStyle in my XAML, I was able to manipulate the IsExpanded property.

<Style x:Key="TreeViewItemContainerStyle" TargetType="{x:Type tp:RadTreeViewItem}">
    <Setter Property="IsExpanded" Value="{Binding IsExpanded, Mode=TwoWay}"/>
    <EventSetter Event="MouseEnter" Handler="RadTreeViewItem_MouseEnter"/>
</Style>

 

private void RadTreeViewItem_MouseEnter(object sender, MouseEventArgs e)
{
    var hoveredItem = sender as RadTreeViewItem;
    if (hoveredItem.IsExpanded)
        hoveredItem.IsExpanded = false;
    else
        hoveredItem.IsExpanded = true;
}

[Petar Mladenov]

Hello Emilio,

I would also suggest the following which avoid the code behind:

<Style TargetType="telerik:RadTreeViewItem">
               <Setter Property="IsExpanded" Value="{Binding IsMouseOver, RelativeSource={RelativeSource Self}}" />
           </Style>

Regards,
Petar Mladenov
Telerik by Progress