Question

I want to inject some views from an xml layout to a RoboFragment but unfortunately I am getting Nullpointer Exception. Since RoboGuice (besides being a great DI framework) has very little documentation, I don’t know if I can use @ContentView(R.layout.fragmentlayout) to annotate my RoboFragment. Is there something I should do instead? What I currently do is:

public class TestFragment extends RoboFragment {

    @InjectView(R.id.upBtn) private Button upBtn;   

    @Override
    public View onCreateView(LayoutInflater layoutInflater, 
            ViewGroup container, Bundle savedInstanceState) {

        super.onCreateView(layoutInflater, container, savedInstanceState);
        View view = layoutInflater.inflate(R.layout.fragmentlayout, container, false);
        RoboGuice.getInjector(getActivity()).injectMembers(this);
        upBtn.setSelected(false);   // <------ Null pointer here
        return view;
    }
}

Answer 1

If you look at the source for RoboFragment, you’ll see

@Override
public void onViewCreated(View view, Bundle savedInstanceState) {
    super.onViewCreated(view, savedInstanceState);
    RoboGuice.getInjector(getActivity()).injectViewMembers(this);
}

If you insist on injecting manually, use injectViewMembers(). If you can delay touching the view until after onViewCreated(), then it will be set up for you.