Design is about prioritizing and making compromises, and there is no single correct solution to any design problem. The outcome and details that we showed in this design challenge will vary depend on the questions y…

Let’s go back and take a higher look at the figure above. In general, the ViewModel receives the user interaction from the View, fetches data from the Model, then process the data to a set of ready-to-display properties. The View updates itself after observing the change of the ViewModel. That’s the whole story of the MVVM.

** Primary QoS: