Can't retain nested fragments

Question

Is there another way of saving the state of the nested fragment ? Or if we shouldn\'t do this, why ? Thanks !

02-13 11:42:43.258: E/AndroidRuntime(7167): ja         


        

Answer 1

Problem: mChildFrgamentManager is being recreated (https://code.google.com/p/android/issues/detail?id=74222)
Workaround: Retaining mChildFrgamentManager if fragment has setRetainInstance(true):

@Override
public void onAttach(Activity activity) {
    super.onAttach(activity);

    if (getRetainInstance()) {
        if (mRetainedChildFragmentManager != null) {
            try {
                Field childFMField = Fragment.class.getDeclaredField("mChildFragmentManager");
                childFMField.setAccessible(true);
                childFMField.set(this, mRetainedChildFragmentManager);
            } catch (NoSuchFieldException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            }
        } else {
            mRetainedChildFragmentManager = getChildFragmentManager();
        }
    }
}

Warning: With this code, setRetainInstace should be called before onAttach.

P.S: This is a bit improved version of @attels answer.