The MVP pattern has varying means by which it is implemented in practice. For example, some implementations of MVP utilize a contract to describe the interaction between the view and presenter.

In addition, there are implementations of MVP that utilize lifecycle callbacks within the presenter, such as onCreate(). This is in an attempt to mirror callbacks existing in the activity lifecycle. Other implementations discard the implementation of these callbacks entirely.

In reality, there is no one true implementation of MVP in Android applications, but there are best practices that can be followed while implementing MVP. You will learn about these best practices and have hands-on experience with developing an MVP application with Kotlin in Chapter 5, Building the Messenger Android App.