You can modify the look of the RadTreeListView and its elements by modifying the RadGridView`s ControlTemplates. As the RadTreeListView inherits the RadGridView, it uses the same styling mechanism. So what you need to do is Edit the GridViewToggleButtonTemplate(represents the button that expands the row and is of type GridViewToggleButton) from the
Control Templates of the RadGridView as per the following article - Editing Control Templates
Marcus, what could be useful in your situation is to use only one RadTreeListView control and synchronize it with two RadGridViews in order to avoid changing the styles. I have attached a sample project which you can review and, if suitable, consider implementing at your end.
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