InjectView in RoboFragment

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;
    }
}

I hope you took a look to these two questions: http://stackoverflow.com/questions/9780769/android-roboguice-inject-views-on-fragment and http://stackoverflow.com/questions/8289660/any-simple-examples-using-roboguice-with-fragments-in-android — Eugen Martynov, Jan 14 '13 at 11:31
Yes. The first one just points out that the injection happens during onViewCreated but I don't unsterstand how. In the second one I also tried RoboGuice.getInjector(getActivity()).injectViewMembers(this); but it didn't help. — Thomas Kaliakos, Jan 14 '13 at 12:35

score 14 · Accepted Answer · answered Jan 15 '13 at 18:05

14

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.

answered Jan 15 '13 at 18:05

RonU

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Ok you are right. I didn't accept the answer all this time because I was still getting a null pointer, but for another reason (I was setting the button listener in onCreateView). I apologize for my retardness.. – Thomas Kaliakos Jan 29 '13 at 08:08
although @ContextView didn't work...do you maybe know if this is possible? – Thomas Kaliakos Jan 29 '13 at 11:59
I don't think so. Looking at the source of of ContentView, RoboActivity, and ContentViewListener, it appears you're only going to be able to use @ContentView with RoboActivities. Fragments are inflated in their #onCreateView method as you did in the original question. – RonU Jan 29 '13 at 21:45

Tsunaze · Answer 2 · 2013-01-09T08:48:24.037

-3

You need to return view. After upBtn.setSelected(false);

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 = (Button) view.findViewById(YOUR_ID); // Initialization
    upBtn.setSelected(false);   // <------ Null pointer here
 return view;
}

edited Jan 09 '13 at 08:48

answered Jan 08 '13 at 14:09

Tsunaze

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1

This won't solve `NullPointerException`. But you're right, OP has forgotten the return statement in their question (not in his real code). – jelies Jan 08 '13 at 19:54
1

No it doesn't work, sorry. The code actually included the return statement. If it was missing I would get a compilation error. – Thomas Kaliakos Jan 09 '13 at 08:45
The problem is related to dependency injection (roboguice), not in the code itself. He asked how to inject `upBtn` view in a fragment. Recently I had the same problem and finished using `view.findById(...)` but I'm interested in a solution that involves `@ContentView(...)`. – jelies Jan 09 '13 at 08:54

InjectView in RoboFragment

2 Answers2