How do I create a ViewModel for each page in a ViewPager?

Question

I have a ViewPager, where I show multiple instances of PetFragment. To create a new instance of a PetFragment, I call PetFragment.newInstance(petId).

I want a separate ViewModel instance for each petId. But ViewModelProvider.Factory#create() only takes a Class<T> as a parameter. How do I achieve this?

is your problem solved ? . I too have same problem . https://stackoverflow.com/questions/54862222/viewpager-with-viewmodel-and-live-data-all-6-tabs-data-is-replaced-by-last-tab — karthik kolanji, Feb 25 '19 at 14:36

Bryan Dormaier · Answer 1 · 2018-02-12T22:23:01.343

4

Take a look at ViewModelProvider.get(@NonNull String key, @NonNull Class<T> modelClass), you should be able to have multiple ViewModels for a specific class stored by key.

ViewModelProvider.get(@NonNull Class<T> modelClass) just calls that first method with a default key.

The get call interacts with ViewModelStore which is a wrapper around a HashMap<String, ViewModel>, which should allow you to store various ViewModels for the same type of Fragment, as long as each has a key that's unique to identifying what it should display.

edited Feb 12 '18 at 22:23

answered Feb 09 '18 at 18:24

Bryan Dormaier

800
6
10

nice. this helped me. – filthy_wizard Jan 18 '19 at 16:24
tried same didn't worked for me .https://stackoverflow.com/questions/54862222/viewpager-with-viewmodel-and-live-data-all-6-tabs-data-is-replaced-by-last-tab – karthik kolanji Feb 25 '19 at 13:59

How do I create a ViewModel for each page in a ViewPager?

1 Answers1