setFragmentResult doesn't work onClick listener

Question

hello my problem is the following, I have 2 fragments, one receives with SetFragmentResultListener and another sends with setFragmentResult

The problem is that setFragmentResult does not work inside an OnClickListener but it does work outside

Parent

 setFragmentResultListener("scannedCode") { requestKey, bundle ->
                val result = bundle.getString("code")
                Log.i("MYLOG-find","$result")
            }

Child - It Work

override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        // Inflate the layout for this fragment
        val view = inflater.inflate(R.layout.fragment_scan, container, false)

            setFragmentResult("scannedCode", bundleOf("code" to  "pedro"))
        
        return view
    }

Child - It doesn't Work

 override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {
        // Inflate the layout for this fragment
        val view = inflater.inflate(R.layout.fragment_scan, container, false)

        view.textView2.setOnClickListener {
            setFragmentResult("scannedCode", bundleOf("code" to  "pedro"))
        }

        return view
    }

This is the parent fragment https://ibb.co/GRJzKvL And this is the child fragment https://ibb.co/sRPKDbK — Sebastian Labadie, Feb 17 '21 at 19:49
main fragment has setFragmentResultListener, in secondary fragment red lines don't work, blue line works fine — Sebastian Labadie, Feb 17 '21 at 19:51
It seems like you're using the Navigation Component (and these aren't actually parent/child fragments i.e., using `childFragmentManager`). Is there a reason you aren't using the [Navigation API for returning a result](https://developer.android.com/guide/navigation/navigation-programmatic#returning_a_result)? — ianhanniballake, Feb 17 '21 at 19:52
Also, what do you mean by 'they don't work'? Fragment Results are only sent when the listening fragment is `STARTED`, which wouldn't be the case if you're navigating to another fragment. — ianhanniballake, Feb 17 '21 at 19:54
so @Ianhanniballake you mean I can only return data while the main fragment is STARTED? — Sebastian Labadie, Feb 17 '21 at 20:01

score 19 · Answer 1 · answered Aug 30 '21 at 11:23

As per @ianhanniballake's answer, I went a bit further, because I had a similar problem, and read the documentation he referred (specially, the Receive results in the host activity section). One of the keys in making inter-fragment communication (parent-child) is to use activity's supportFragmentManager methods to perform the information exchange. Example:

Parent fragment (host)

requireActivity().supportFragmentManager
   .setFragmentResultListener("whatever_id_you_use", viewLifecycleOwner) {
   // Your code for listener
}

Child fragment:

requireActivity().supportFragmentManager
   .setFragmentResult("whatever_id_you_use", bundle_with_results)

"whatever_id_you_use" is the requestKey depicted in documentation, which is the index the activity will look for when assigning a listener to its result. Doing this way should keep the listeners in sync with the lifecycle, while simplifying own listener's implementation.

but what if we simply use this setFragmentResult("whatever_id_you_use", bundle_with_results) — Qamar khan, May 16 '22 at 20:28

score 13 · Answer 2 · edited Sep 02 '21 at 09:14

In the case of passing data from Child to Parent fragment, using the childFragmentManager is the key when setting the resultListener on the parent fragment.

Parent fragment (place the code inside onCreate()):

childFragmentManager.setFragmentResultListener("requestKey", this ) { requestKey, bundle ->
            val resultReceived = bundle.getString("bundleKey")
            // do something with the result
            // ...  
        }

Child fragment (place the code whenever you need to send the result - could be from a click listener, could be once you receive a result from another started activity for result, etc.):

 val resultToBeSent = "result"
 setFragmentResult("requestKey", bundleOf("bundleKey" to resultToBeSent))

More useful information about the communication between fragments can be found in this medium article: The modern way to pass data between fragments and of course in the official Android documentation: Communicating with fragments.

score 5 · Answer 3 · answered Feb 17 '21 at 20:01

When you use the Navigation Component, the previous fragment is stopped when you navigate to a new fragment. As per the Fragment Result API guide:

If you call setFragmentResult() more than once for the same key, and if the listener is not STARTED, the system replaces any pending results with your updated result. If you set a result without a corresponding listener to receive it, the result is stored in the FragmentManager until you set a listener with the same key. Once a listener receives a result and fires the onFragmentResult() callback, the result is cleared. This behavior has two major implications:

Fragments on the back stack do not receive results until they have been popped and are STARTED.

If a fragment listening for a result is STARTED when the result is set, the listener's callback is then fired immediately.

So it is expected that you do not get any calls to your fragment result listener until you pop back to that fragment and it becomes STARTED again.

score 0 · Answer 4 · edited Dec 24 '21 at 22:37

0

In my case sending result from pushed fragment to presenting, I need to call: requireActivity().onBackPressed(), then setFragmentResult().

edited Dec 24 '21 at 22:37

answered Dec 06 '21 at 19:15

bluestart83

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setFragmentResult doesn't work onClick listener

4 Answers4