Implement a Tri-state CheckBox using MVVM with TreeView
Some applications use checkboxes that allow an indeterminate state in addition to the two provided by a normal checkbox. This third state is shown as a dash in the checkbox, and indicates that its state is neither checked nor unchecked. This is most often used when the checkbox is tied to a collection of items in mixed states. In this video, we are going to investigate how you would do this using the RadTreeView control and the MVVM Pattern.