When using MVVM design style for a Silverlight or WPF control, it is common to use the control’s DataContext to keep the associated ViewModel instance, so that in the XAML file for the control one can use simple binding statements from the UI to the view model (and back if TwoWay binding mode is specified) [...]

While refactoring ClipFlair code to use MVVM (Model-View-ViewModel) pattern, I came across the XAML error “Object reference not set to an instance of an object.”, shown in Visual Studio when trying to bind to my ViewModel (accessed implicitly, being set as the DataContext of the XAML control) for a property named Source. I have settled [...]