Android ViewModel additional arguments

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You need to have a factory class for your ViewModel.

public class MyViewModelFactory implements ViewModelProvider.Factory {
    private Application mApplication;
    private String mParam;


    public MyViewModelFactory(Application application, String param) {
        mApplication = application;
        mParam = param;
    }


    @Override
    public <T extends ViewModel> T create(Class<T> modelClass) {
        return (T) new MyViewModel(mApplication, mParam);
    }
}

And when instantiating the view model, you do like this:

MyViewModel myViewModel = ViewModelProvider(this, new MyViewModelFactory(this.getApplication(), "my awesome param")).get(MyViewModel.class);

For kotlin, you may use delegated property:

val viewModel: MyViewModel by viewModels { MyViewModelFactory(getApplication(), "my awesome param") }

There’s also another new option – to implement HasDefaultViewModelProviderFactory and override getDefaultViewModelProviderFactory() with the instantiation of your factory and then you would call ViewModelProvider(this) or by viewModels() without the factory.

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