View in the MVVM architecture

What is View in the MVVM architecture?

The View component in the MVVM architecture are the UI controllers – Activities and Fragments. They should be as free as possible from any business logic. Their role is to present the data, not to transform it. The view should contain only UI related logic. It is a common misconception to write all the logic for a particular screen in the corresponding Activity or Fragment. By doing so, we create God classes and we break the single responsibility principle. So we should always try to keep our View as clean as possible.
The View asks the ViewModel for data. The View doesn’t care where the data comes from, what kind of transformations are applied to it and so on. It only knows how to properly display the data on the screen. When the data is changed by user interactions with the UI components, the View calls the ViewModel’s methods and passes the changed data to them. Again, it is unaware of how the data is processed.
Share :
Share :

Weitere Beiträge

ViewModel

ViewModel – it is a model of the view. The purpose of the ViewModel is to apply any business logic to the Model before exposing it to the View for consumption. This way the View is free of business logic.

Weiterlesen »
Repository in Android’s MVVM architecture

Repository is a class which purpose is to provide a clean API for accessing data. What that means is that the Repository can gather data from different data sources(different REST APIs, cache, local database storage) and it provides this data to the rest of the app.

Weiterlesen »