title: How to organize architecture WPF project?
body: <p>In my WPF project i want to have only one Window - MainWindow and UserControls as working part. I have some little different applications in one, and want to make navigation on top of my MainWindow as buttons. And little applications as UserControl. In MainWindow - grid with Big Empty Zone - which use to keep and run work. But, i want to navigate to other userControl from another. (probably do not understand :()</p>
  
  <p>How organize architecture WPF project that: one main window and many usercontrols which places in mainwindow and replace each other in turn. and there is the possibility of navigating from another usercontrol to another.</p>
  
  <p>May be it's MVVM, but i don't understand how this pattern can help me.</p>