In order to offer a way of showing a multi-level hierarchy in a comprehensible way, we introduced connecting lines for RadTreeListView.
The tree lines support was added as of version Q2 2014.
The functionality can be configured through the following properties:
TreeLinesVisibility – controls the visibility of the TreeLines. It is of type Telerik.Windows.Controls.TreeList.TreeLinesVisibility and its possible values are listed below:
TreeLinesBrush – controls the Brush (Color) of the tree lines. It is of type System.Windows.Media.Brush
TreeLinesStrokeThickness – controls the thickness of the tree lines. It is of type double
Figure 1: RadTreeListView with tree lines visible. The TreeLinesStrokeThickness is set to 10.
You can also check out the "Tree Lines" WPF Demo.