Detect pop in Navigation Component

Question

In Navigation Component, how can one detect if fragment is brought to front from a pop event?

I go from A to B, now I close B using back key, it returns to A, now in A (in onViewCreated event) I want to detect it's coming from B.

Answer 1

If we're using a single NavController.

findNavController((R.id.nav_host_fragment)
    .addOnDestinationChangedListener{ hostController, destination, _ ->
        val push = currentBackStackSize < hostController.bacStack.size // else pop
        // Then save current backstack size
  }

This solution might not be always correct, but currently I can't think of an edge case. Please feel free to correct me.