title: Extending user controls in WPF
body: <p>I have built a User Control composed, as usual, of a XAML part and a code-behind part. Now, I need to create another User Control which shares some of the functionalities of the former, but which has different looks and might also have additional features in the code-behind. </p>
  
  <p>My first idea was to create an interface to gather the common functionalities of the two types of controls. Is this the right way to go? And how would I manage the different XAML parts I should have? Any advice is welcome.</p>