TareKhoury TareKhoury - 1 month ago 12
Android Question

Android Fragment onAttach() deprecated

I have updated my app to use the latest support library (version 23.0.0), I've found out that they deprecated the onAttach() function of the Fragment class.

Instead of:

onAttach (Activity activity)


It's now:

onAttach (Context context)


As my app uses the activity passed before deprecation, a possible solution i think is:

@Override
public void onAttach(Context context) {
super.onAttach(context);
activity = getActivity();
}


Would that be the correct way to do it?

UPDATE:

If i run a device with API lower than 23, the new onAttach() is not even being called. I hope that this is not what they intended to do!

UPDATE 2:

Issue has been resolved with the latest updates to the SDK.

I have tested on my API 22 device and onAttach(Context) is being called.

Click here to follow the bug report I've opened a couple of weeks ago and the answers from the guys at Google.

Answer

Activity is a context so if you can simply check the context is an Activity and cast it if necessary.

@Override
public void onAttach(Context context) {
    super.onAttach(context);

    Activity a;

    if (context instanceof Activity){
        a=(Activity) context;
    }

}

Update: Some are claiming that the new Context override is never called. I have done some tests and cannot find a scenario where this is true and according to the source code, it should never be true. In all cases I tested, both pre and post SDK23, both the Activity and the Context versions of onAttach were called. If you can find a scenario where this is not the case, I would suggest you create a sample project illustrating the issue and report it to the Android team.

Update 2: I only ever use the Android Support Library fragments as bugs get fixed faster there. It seems the above issue where the overrides do not get called correctly only comes to light if you use the framework fragments.

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