Multi tool use

warp MVP presenter inside viewmodel in android?

one of mvp presenter pattern disadvantages is handling activity state or orientation change , while viewmodel survive orientation changes , so can i wrap presenter inside a viewmodel and still using MVP ?

2 Answers
2

You can, of course, have a presenter that lives inside a ViewModel to survive configuration changes, and live for the same time as the Activity or Fragment does.

ViewModel

Activity

Fragment

You could also make your presenter itself the ViewModel subclass, or even use MVVM with the view component observing LiveData from the ViewModel, to be automatically safe with lifecycle handling at that point (as seen being pushed by Google recently).

ViewModel

MVVM

LiveData

ViewModel

Actually, MVP MVVM and MVC are all just design patterns.
None of them inherently solve problems imposed by a particular platform.
They aim to provide a mechanism for developers to organize the structure of code into logical roles under the segregation of responsibility principle (see SOLID software engineering).

The problem of state preservation in relation to configuration changes in Android Activities (Rotation is just one of these) is present as a feature of the Android operating system.
Google has built-in one solution to their Architectural components, which I presume you are referring to as ViewModel but that doesn't mean MVVM as a pattern supports it directly.

ViewModel

As mentioned by @zsmb13 , you can fairly cleanly use the viewmodel as a presenter.

As far as state preservation goes though, I have another approach here: ucs Framework and a little article about one of the approaches here: A Simple MVP approach for Android - The Simple MVP approach is now deprecated in favor of the ucs framework which in addition to state preservation also manages threading.

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