Highlight whole TreeViewItem line in WPF

Question

If I set TreeViewItem Background it highlights the header only. How can I highlight the whole line?

I have found a post almost solving a problem http://social.msdn.

Answer 1

For a XAML only approach I've taken one of Bendewey's solutions and broken it up a bit into a more basic solution:

The style below should allow Treeview items to span:

In order to get it to operate and collapse like a proper Treeview the below triggers should allow this:

Just nest the triggers within the Control Template. Colours/padding/design will need to be tweaked to suit your own needs but the above should be a very basic idea on a XAML only foundation.