MVVM can be seen as an augmentation of MVC. Introducing the view model concept, it recognizes that not every view concerned with a dataset will be using this data in the same way. It adds a layer of indirection between a view and a model, called a view model, to solve this issue. It also keeps separation of concerns to the fore; why should the model, which is dealing with our data be concerned about anything to do with our view, which is dealing with presentation?
A typical representation of MVVM
With Ext JS 5, MVVM is wholeheartedly embraced. The sample application structure that Sencha Cmd generates will provide a ViewModel class alongside the View class. This has tight integration into the View class via new configuration options, which make it a first-class citizen when trying to solve the common problems that arise in a large MVC application, as we discussed earlier.
In addition, a ViewController class is created to encapsulate the logic you'd...