Can't find ViewModelProviders class, only ViewModelProvider

Question

I am trying to create lifecycle-aware view models. But I can't find ViewModelProviders class in my Android project, only ViewModelProvider. There seems to be no android.arch.lifecycle.ViewModelProviders package for me to import as well. What's happening

Existential

Answer 1

You probably have this dependency included in your project:

implementation "android.arch.lifecycle:viewmodel:$lifecycle_version"

That contains ViewModelProvider (and just 4 other classes), but ViewModelProviders is in a different package:

implementation "android.arch.lifecycle:extensions:$lifecycle_version"

Here are the contents of these packages for reference (as of version 1.1.1):

---

For the record, you can find this out yourself by looking up the docs for the ViewModelProviders class, where it says up top:

added in version 1.1.0

belongs to Maven artifact android.arch.lifecycle:extensions:1.1.1

Pipit

Thanks. Here is some more detailed info about adding LifeCycle components into your project developer.android.com/topic/libraries/architecture/… – Existential

With API 29, the architecture components have been moved to the androidx.* namespace. You should therefore use implementation "androidx.lifecycle:lifecycle-extensions:$lifecycleVersion" and implementation "androidx.lifecycle:lifecycle-viewmodel:$lifecycleVersion". At the time of writing this, using $lifecycleVersion='2.0.0-rc1' will work. Note that the libs are backwards compatible, so this will also work for apps with API compatibility < 29. – Wanonah

Answer 2

Also, just for future reference.

ViewModelProviders class is now deprecated. According to Android Developers Documentation: ViewModelProviders

This class is deprecated. Use the constructors for ViewModelProvider directly.

Salliesallow

This should be the new right answer! – Wanderjahr