MasterActivity.java

public class MasterActivity extends AppCompatActivity {

    private MainViewModel viewModel;
  
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        viewModel = ViewModelProviders.of(this).get(MainViewModel.class);
        
        if (savedInstanceState != null) {
            String dataId = savedInstanceState.getString("dataId");
            viewModel.setDataId(dataId);
        }
    }
    
    @Override
    protected void onPause() {
        super.onPause();
        viewModel.onPause();
    }
  
    @Override
    protected void onSaveInstanceState(Bundle outState) {
        super.onSaveInstanceState(outState);
        String dataId = viewModel.getDataId();
        outState.putString("dataId", dataId);
    }
}