title: Flow of control in WPF application
body: <p>In WPF application I have <code>MainWindow : Window</code> which loads a <code>POSView : UserControl</code>.</p>
  
  <p>POSView has to automatically show some data to an user when main window loads.</p>
  
  <p>POSView is bound to its ViewModel class properties, which in turn is bound to a model properties.</p>
  
  <p>I am trying to follow the MVVM pattern. My question is who should populate my model with data. </p>
  
  <p>Apparently some object of a class, that monitors for MainWindow or POSView events (to know when it has been loaded and ready to display data) and at this point reads data from a remote WCF service (in my case) and populates the model with it.</p>
  
  <p>Who creates this class? </p>
  
  <p>Which is the best way to monitor for POSView readiness to "eat data"?</p>
  
  <p>Thank you.</p>