(MVVM) Model View View Model

Improvement from MVC, MVP to a better Architecture

• To overcome the drawbacks of MVC, MVP architecture modifications were done to segregate it to a better representation of architecture called Model-View-ViewModel.
• It is one of the very popular ways of structuring the android code.
• MVVM helps you to separate your code into many layers that let you have your own responsibilities.
• Code becomes more readable, testable, maintainable.
• The codebase stands the test of time.

Contents
MVVM block diagram
MVP + Repository Pattern block diagram
Using the android architecture component in MVP

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MVP block diagram

• Different people use different variations of the MVP pattern.
• Common and the most popular type of MVP pattern is by using a contract between the view and the presenter
• The contract is an interface between the view and the presenter
• The view calls a method to initiate an action in the presenter, the action can be to fetch the data from the model.
• Finally once the data is retrieved from the model the presenter notifies the view via the callback from the contract.

MVP + Repository Pattern block diagram

• A repository is used to manage the data from API and loacal database.
• We condider Model = Repository + API + Local Database

Using the android architecture component in MVP

• Why not - of course, yes.
• Instead of the contract that exists between view and presenter, We can use a LiveData