title: ItemsControl with multiple DataTemplates for a viewmodel
body: <p>is it possible to bind an itemscontrol with canvas as template to multiple DataTemplates?</p>
  
  <p>I have 2 collections and depending on the type I would like to display a different control on my canvas.</p>
  
  <p>I am not sure but I could think about a Viewmodel which has 2 ObservableCollections. For example if I would have "Shapes" and "connections" and I would like to display them both on the canvas? In case of a diagraming scenario...</p>
  
  <p>I would like to do this in the mvvm manner and I am not sure if the multiple DataTemplate approach is correct but this came to my mind. 
  But I am still having problems to get the binding straight in my head. If I set the DataContext to the ViewModel for me it seems not possible to bind 2 collections to the items control... =(
  I am also open for other ideas, too....</p>
  
  <p>Is this possible? And if so, how would the binding look like an</p>