How to get Context in Android MVVM ViewModel

android mvvm dagger-2 android-context
Vincent Williams picture Vincent Williams · Jul 21, 2018 · Viewed 70.4k times · Source

I am trying to implement MVVM pattern in my android app. I have read that ViewModels should contain no android specific code (to make testing easier), however I need to use context for various things (getting resources from xml, initializing preferences, etc). What is the best way to do this? I saw that AndroidViewModel has a reference to the application context, however that contains android specific code so I'm not sure if that should be in the ViewModel. Also those tie into the Activity lifecycle events, but I am using dagger to manage the scope of components so I'm not sure how that would affect it. I am new to the MVVM pattern and Dagger so any help is appreciated!

Answer

Jay picture Jay · Oct 30, 2018

You can use an Application context which is provided by the AndroidViewModel, you should extend AndroidViewModel which is simply a ViewModel that includes an Application reference.

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