public class MainActivity extends LifecycleActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        mViewModel = ViewModelProviders.of(this).get(ListIssuesViewModel.class);
        setupView();
        // Handle changes emitted by LiveData
        mViewModel.getRes().observe(this, apiResponse -> {
            if (apiResponse.getError() != null) {
                handleError(apiResponse.getError());
            } else {
                handleResponse(apiResponse.getIssues());
            }
        });
    }

  // Rest of the code

}