How to hide a view in the host activity from other fragment using navigation-CodePudding

activity_main.xml

 <androidx.fragment.app.FragmentContainerView
   android:id="@ id/nav_host_fragment"
   android:name="androidx.navigation.fragment.NavHostFragment"
   android:layout_width="0dp"
   android:layout_height="0dp"
   app:layout_constraintLeft_toLeftOf="parent"
   app:layout_constraintRight_toRightOf="parent"
   app:layout_constraintTop_toTopOf="parent"
   app:layout_constraintBottom_toBottomOf="parent"
   app:defaultNavHost="true"
   app:navGraph="@navigation/nav_graph" >
</androidx.fragment.app.FragmentContainerView>

<androidx.constraintlayout.widget.ConstraintLayout
  android:id="@ id/bottom_controls"
  android:layout_width="match_parent"
  android:layout_height="72dp"
  android:onClick="onSongInfoClick"
  android:background="@drawable/lyt_rounded_bottom_music"
  android:paddingStart="10dp"
  android:paddingEnd="10dp"
  android:elevation="25dp"
  app:layout_constraintTop_toBottomOf="@id/nav_host_fragment">

The start destination is a ViewPagerFragment consisting of various tabs.

When I click the bottom_controls view from activity_main I am navigating to SongDetailsFragment

I don't want to show that bottom_controls in songDetailsFragment

Here's how i'm trying to do it:

MainActivity.kt

val currentFragment = supportFragmentManager.currentNavigationFragment
if(currentFragment !== SongDetailsFragment())
{
  viewModel.showMiniPlayer()
}
else{
  viewModel.hideMiniPlayer()
}

SongDetailsFragment.kt

class SongDetailsFragment : BaseSongDetailFragment() {
  .....
}

BaseSongDetailFragment.kt

 open class BaseSongDetailFragment : Fragment() {

 private val songDetailViewModel by sharedViewModel<SongDetailViewModel>()
 protected val mainViewModel by inject<MainViewModel>()


 override fun onActivityCreated(savedInstanceState: Bundle?) {
  super.onActivityCreated(savedInstanceState)
  showHideBottomSheet()
 }

 override fun onPause() {
 showHideBottomSheet()
 super.onPause()
 }

 override fun onResume() {
 showHideBottomSheet()
 super.onResume()
}

private fun showHideBottomSheet() {
 val currentData = songDetailViewModel.currentData.value ?: return
 if (currentData.id == 0L) return

 val currentFragment = 
 requireActivity().supportFragmentManager.currentNavigationFragment

 if(currentFragment ==  this as SongDetailsFragment){
    mainViewModel.hideMiniPlayer()
 }

 else{
     mainViewModel.showMiniPlayer()
  }
 } 
}

Problem:

The very first time I launch the app and navigate to songDetailsFragment, it shows the bottom_controls view.

Subsequently, it doesn't show.

I want it to not show at all.

CodePudding user response：

You can use OnDestinationChangedListener in your activity to listen to changes in currentDestination.

navController.addOnDestinationChangedListener { _, destination, _ ->
    if (destination.id == R.id.songDetailsFragment)
        viewModel.hideMiniPlayer()
    else
        viewModel.showMiniPlayer()
}