Implementing the Model

Abstract

When I started writing this book, I took some time before determining the current order of chapters 2 , 3 and 4 . There is always a great debate for MVVM implementation about what you design and implement first; Model, View or ViewModel? Theoretically if you look at the core of the Model-View-ViewModel design pattern, ViewModel is at the heart of the design implementation. It ties one or more Views (user interface) with the Model (your data source) by exposing properties on the Model objects and binding it to the Views. This would enable displaying the data as information as part of the application user interface. After giving it a lot of thought, I settled on the current sequence of the chapters, in which we first defined Views in the previous chapter, giving you a visual context; now we will define a lightweight model that determines the data source and required properties; and finally, in next chapter, we will implement ViewModels which will bind the model objects to the Views.