How to retrieve a DialogFragment showed with <dialog> tag in nav.xml (Navigation Component) fr-CodePudding

Nowadays, using navigation component, we have complex apps which manipulate a bunch of fragments flows.

In my app, I have a simple activity with only a <androidx.fragment.app.FragmentContainerView with app:defaultNavHost="true"

Note: In this explanation, I will consider that FragmentContainerView == NavHostFragment

From inner fragments of this activity/main's NavHostFragment, I open sometimes DialogFragment using <dialog> tag of my nav graph. This dialog is using his own NavHostFragment which open a bunch of fragments screen.

Using this representation (yeah 2 overlapping dialogs doesn't sounds good but it's real :p) :

Activity
---- NavHostFragment (id:1, tag:tag_1)
-------- FragmentA
-------- FragmentB
-------- DialogFragmentC (id: dialog_fragment_c)
------------- NavHostFragment (id:2, tag:tag_2)
------------------ FragmentD
------------------ FragmentE
-------- DialogFragmentF (id: dialog_fragment_f)
------------- NavHostFragment (id:3, tag:tag_3)
------------------ FragmentE
------------------ FragmentH

1°) How can I find DialogFragmentC from activity easily

with <dialog> tag in nav graph we are not able to assign a fragment's tag to the supportFragmentManager like old method (show(supportFragmentManager, tagDialog)) perform a findFragmentByTag

For now, I'm using this piece of code:

From MainActivity:

val dialogFragmentC = (supportFragmentManager.findFragmentById(
        R.id.activity_nav_host_fragment // NavHostFragment id of MainActivity
    ) as NavHostFragment).childFragmentManager.fragments.filterIsInstance<DialogFragmentC>().lastOrNull()

it sounds like an ugly code

2°) How can I find DialogFragmentC from FragmentD

From FragmentD:

2.1°) Like this, it doesn't work because NavHostFragment (id:2, tag:tag_2) is attached to activity'supportFragmentManager

requireParentFragment().parentFragment // returns null (requireParentFragment is NavHostFragment (id:2, tag:tag_2))

2.2°) because we know that this fragment is used only in 1 DialogFragment type class, we could use point 1°) to retrieve de DialogFragment

3°) How can I find DialogFragment's FragmentE

FragmentE is used in two different types of DialogFragment. I could expect to act differently depending on which one I'm in.

3.1°) I could perform point 1°) and check on multiple dialogs fragment opened which one has a navHostFragment that successfully match the parentFragment (NavHostFragment (id:2, tag:tag_2) or (id:3, tag:tag_3)) of FragmentE.

If anyone has an idea to simplify this way of doing

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