Android and Fragment result API. How to share result from child fragment with different request key?

Question

I am trying to implement fragment result API in my application. I need to show DialogFragment inside Fragment and send result from dialog fragment to fragment when dialog buttons was clicked. So in my dialog fragment when button was clicked I making smth like this:

  setFragmentResult(requestKey, bundleOf(RESULT to result))

And I'am trying to retrieve result in my fragment inside onCreate():

  childFragmentManager.setFragmentResultListener(requestKey, this) { _, bundle ->
        val result = bundle.getInt(DialogFragment.RESULT)
       // some code
    }

Everything works well, but there is one problem. The requestKey I use when calling the setFragmentResult in my dialog fragment is dynamic.

That is, the dialog can be opened inside the fragment in different cases. And I need to distinguish between these cases. To do this, I send a different request key to the dialog fragment. But how do I, when receiving a result in a fragment, distinguish this result by key. If I do this inside the onCreate() method.

That is, I want to do something like this:

 childFragmentManager.setFragmentResultListener(requestKey, this) { requestKey, bundle ->
            when(requestKey) {
                "FIRST_CASE" -> { // some code }
                "SECOND_CASE" -> { // some code }  
          }
        }

But I do not understand how this can be implemented if this method (setFragmentResultListener) already requires a requestKey as an argument. Where should I take it from?

If my requestKey was static I would create a constant inside the dialog fragment and use it. But my requestKey is dynamic.

Please help me. I did not find a suitable example for me on the Internet. And at the moment I don’t understand how this can be implemented in the context of a clean architecture with MVVM.

P.S. Here is an example of what I want to implement: A fragment that contains two buttons (e.g. A, B). By clicking on each of the buttons, dialog fragment opens, with different text. Inside the dialog there is also a button, by clicking on which the result is transferred to the fragment. I need to process this result differently, depending on which button was pressed on the fragment (A or B). To do this, I wanted to distinguish by request key.

Answer 1

The reason the FragmentResultListener received a requestKey is if you are reusing the same FragmentResultListener in multiple calls to setFragmentResultListener - i.e., if your Fragment itself implemented FragmentResultListener.

In your case, your Fragment isn't implementing the FragmentResultListener, so you can just call setFragmentResultListener twice, once for each key:

childFragmentManager.setFragmentResultListener("FIRST_CASE", this) { _, bundle ->
  // some code
}
childFragmentManager.setFragmentResultListener("SECOND_CASE", this) { _, bundle ->
  // some code
}