Android Navigation Architecture Component - Get current visible fragment

Before trying the Navigation component I used to manually do fragment transactions and used the fragment tag in order to fetch the current fragment.

val fragment:MyFragment = supportFragmentManager.findFragmentByTag(tag):MyFragment

Now in my main activity layout I have something like:

<fragment
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/nav_host"
        app:navGraph= "@navigation/nav_item"
        android:name="androidx.navigation.fragment.NavHostFragment"
        app:defaultNavHost= "true"
        />

How can I retrieve the current displayed fragment by the Navigation component? Doing

supportFragmentManager.findFragmentById(R.id.nav_host)

returns a NavHostFragment and I want to retrieve my shown 'MyFragment`.

Thank you.

I managed to discover a way for now and it is as follows:

NavHostFragment navHostFragment = supportFragmentManager.findFragmentById(R.id.nav_host);
navHostFragment.getChildFragmentManager().getFragments().get(0);

In case of course you know it is the first fragment. I am still investigating a way without this. I agree it is not the best way but that should be something for now.

There is no way I can find to retrieve the current fragment instance. However, you can get the ID of lastly added fragment using the code below.

navController.currentDestination?.getId()

It returns the ID in navigation file. Hope this helps.

You should look the childFragmentManager primaryNavigationFragment property of your nav fragment, this is where the current displayed fragment is referenced.

val navHost = supportFragmentManager.findFragmentById(R.id.main_nav_fragment)
    navHost?.let { navFragment ->
        navFragment.childFragmentManager.primaryNavigationFragment?.let {fragment->
                //DO YOUR STUFF
        }
    }
}

This seems like the cleanest solution. Update: Changed extension function to property. Thanks Igor Wojda.

1. Create the following extension

import androidx.fragment.app.Fragment
import androidx.fragment.app.FragmentManager

val FragmentManager.currentNavigationFragment: Fragment?
    get() = primaryNavigationFragment?.childFragmentManager?.fragments?.first()

2. In Activity with NavHostFragment use it like this:

val currentFragment = supportFragmentManager.currentNavigationFragment

Use addOnDestinationChangedListener in activity having NavHostFragment

For Java

 NavController navController= Navigation.findNavController(MainActivity.this,R.id.your_nav_host);

        navController.addOnDestinationChangedListener(new NavController.OnDestinationChangedListener() {
            @Override
            public void onDestinationChanged(@NonNull NavController controller, @NonNull NavDestination destination, @Nullable Bundle arguments) {
                Log.e(TAG, "onDestinationChanged: "+destination.getLabel());
            }
        });

For Kotlin

var navController :NavController=Navigation.findNavController(this, R.id.nav_host_fragment)
    navController.addOnDestinationChangedListener { controller, destination, arguments ->
        Log.e(TAG, "onDestinationChanged: "+destination.label);

    }

this might be late but for anyone who's still looking

val currentFragment = NavHostFragment.findNavController(nav_host_fragment).currentDestination?.id

then you can do something like

if(currentFragment == R.id.myFragment){
     //do something
}

note that this is for kotlin, java code should be almost the same

First, you get the current fragment by id, then you can find the fragment, depending on that id.

int id = navController.getCurrentDestination().getId();
Fragment fragment = getSupportFragmentManager().findFragmentById(id);

My requirement is to get the current visible fragment from Parent activity,my solution is

 private LoginFragment getCurrentVisibleFragment() {
        NavHostFragment navHostFragment = (NavHostFragment)getSupportFragmentManager().getPrimaryNavigationFragment();
        FragmentManager fragmentManager = navHostFragment.getChildFragmentManager();
        Fragment loginFragment = fragmentManager.getPrimaryNavigationFragment();
        if(loginFragment instanceof LoginFragment){
            return (LoginFragment)loginFragment;
        }
        return null;
    }

This may help some one with same problem.

navController().currentDestination?.id

will give you your current Fragment's id where

private fun navController() = Navigation.findNavController(this, R.id.navHostFragment)

this id is the id which you have given in your Navigation Graph XML file under fragment tag. You could also compare currentDestination.label if you want.

Found working solution.

private fun getCurrentFragment(): Fragment? {
    val currentNavHost = supportFragmentManager.findFragmentById(R.id.nav_host_id)
    val currentFragmentClassName = ((this as NavHost).navController.currentDestination as FragmentNavigator.Destination).className
    return currentNavHost?.childFragmentManager?.fragments?.filterNotNull()?.find {
        it.javaClass.name == currentFragmentClassName
    }
}

Using navigation components, I got the current displayed fragment using this line of code:

val fragment = parentFragmentManager.primaryNavigationFragment

From an Activity that uses NavHostFragment, you can use the code below to retrieve the instance of the Active Fragment.

val fragmentInstance = myNavHostFragment?.childFragmentManager?.primaryNavigationFragment

As per @slhddn answer and comment this is how I'm using it and retrieving the fragment id from the nav_graph.xml file:

class MainActivity : AppCompatActivity() {
override fun onCreate(savedInstanceState: Bundle?) {
    super.onCreate(savedInstanceState)
    setContentView(R.layout.activity_main)

    setSupportActionBar(findViewById(R.id.toolbar))

    val navController = findNavController(this, R.id.nav_host_fragment)

    ivSettingsCog.setOnClickListener {

        if (navController.currentDestination?.id == R.id.updatesFragment) // Id as per set up on nav_graph.xml file
        {
            navController.navigate(R.id.action_updatesFragment_to_settingsFragment)
        }

    }

}

}

Within your activity, hosting the NavHostFragment we can write the following piece of code to fetch the instance of the currently displayed fragment

Fragment fragment = myNavHostFragment.getChildFragmentManager().findFragmentById(R.id.navHostFragmentId)
if(fragment instanceOf MyFragment) {
  //Write your code here
}

Here R.id.navHostFragmentId is the resId for the NavHostFragment within your activity xml

Make :

• in some button in your fragment:

val navController = findNavController(this)
  navController.popBackStack()

• In your Activity onBackPressed()

override fun onBackPressed() {
        val navController = findNavController(R.id.nav_host_fragment)
        val id = navController.currentDestination?.getId()
        if (id == R.id.detailMovieFragment){
            navController.popBackStack()
            return
        }

        super.onBackPressed()
    } 

The first fragment in navhost fragment is the current fragment

Fragment navHostFragment = getSupportFragmentManager().getPrimaryNavigationFragment();
if (navHostFragment != null) 
{Fragment fragment = navHostFragment.getChildFragmentManager().getFragments().get(0);}

The best way I could figure out with 1 fragment, Kotlin, Navigation usage:

On your layout file add the tag: "android:tag="main_fragment_tag""

<fragment
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/nav_host"
        app:navGraph= "@navigation/nav_item"
        android:tag="main_fragment_tag"
        android:name="androidx.navigation.fragment.NavHostFragment"
        app:defaultNavHost= "true"
        />

On your Activity:

val navHostFragment = supportFragmentManager.findFragmentByTag("main_fragment_tag") as NavHostFragment
val mainFragment = navHostFragment.childFragmentManager.fragments[0] as MainFragment
mainFragment.mainFragmentMethod()

Here is my solution for java

    NavHostFragment  navHostFragment= (NavHostFragment) getSupportFragmentManager().getFragments().get(0);
    MyFragment  fragment = (MyFragment) navHostFragment.getChildFragmentManager().getFragments().get(0);
    fragment.doSomething();

can you please check with getChildFragmentManager() call with

NavHostFragment fragment = supportFragmentManager.findFragmentById(R.id.nav_host);
MyFragment frag = (MyFragment) fragment.getChildFragmentManager().findFragmentByTag(tag);

If you need the instance of your fragment, you can go with:

(Activity) => supportFragmentManager.fragments.first().childFragmentManager.fragments.first()

It's very ugly but from there you can check if it's an instance of the fragment you want to play around with

On Androidx, I have tried many methods for finding out required fragment from NavHostFragment. Finally I could crack it with below method

public Fragment getFunctionalFragment (String tag_name)
{
    NavHostFragment navHostFragment = (NavHostFragment) getSupportFragmentManager().findFragmentById(R.id.nav_host_fragment);
    FragmentManager navHostManager = Objects.requireNonNull(navHostFragment).getChildFragmentManager();

    Fragment fragment=null;
    List fragment_list = navHostManager.getFragments();

    for (int i=0; i < fragment_list.size() ; i ++ )
    {
        if ( fragment_list.get(i) instanceof HomeFragment && tag_name.equals("frg_home")) {
            fragment = (HomeFragment) fragment_list.get(i);
            break;
        }
    }

    return fragment;
}

This code works from me

NavDestination current = NavHostFragment.findNavController(getSupportFragmentManager().getPrimaryNavigationFragment().getFragmentManager().getFragments().get(0)).getCurrentDestination();

switch (current.getId()) {
    case R.id.navigation_saved:
        // WRITE CODE
        break;
}

this might be late but may help someone later.

if you are using nested navigations you can get id like this in Kotlin

val nav = Navigation.findNavController(requireActivity(), R.id.fragment_nav_host).currentDestination

and this is one of fragments in fragment_nav_host.xml

<fragment
    android:id="@+id/sampleFragment"
    android:name="com.app.sample.SampleFragment"
    android:label="SampleFragment"
    tools:layout="@layout/fragment_sample" />

and you can check all you need like this

if (nav.id == R.id.sampleFragment || nav.label == "SampleFragment"){}

Finally the working solution for those of you who are still searching Actually it is very simple and you can achieve this using callback.

follow these steps:

1. Create a listener inside the fragment you want to get the instance from activity onCreate()

   public class HomeFragment extends Fragment {
   
   private OnCreateFragment createLIstener;
   
   public View onCreateView(@NonNull LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
       createLIstener.onFragmentCreated(this);
       View root = inflater.inflate(R.layout.fragment_home, container, false);
       //findViews(root);
       return root;
   }
   
   @Override
   public void onCreateOptionsMenu(@NonNull Menu menu, @NonNull MenuInflater inflater) {
       super.onCreateOptionsMenu(menu, inflater);
       inflater.inflate(R.menu.menu_main, menu);
       
   }
   
   @Override
   public boolean onOptionsItemSelected(@NonNull MenuItem item) {
       if (item.getItemId()==R.id.action_show_filter){
           //do something
       }
       return super.onOptionsItemSelected(item);
   }
   
   @Override
   public void onAttach(Context context) {
       super.onAttach(context);
       try {
           createLIstener = (OnCreateFragment) context;
       } catch (ClassCastException e) {
           throw new ClassCastException(context.toString() + " must implement OnArticleSelectedListener");
           }
       }
   
       public interface OnCreateFragment{
           void onFragmentCreated(Fragment f);
       }
   }
   

2. Implement your listener in the host Fragment/Activity

   public class MainActivity extends AppCompatActivity implements HomeFragment.OnCreateFragment {
   
       @Override
       protected void onCreate(Bundle savedInstanceState) {
           super.onCreate(savedInstanceState);
           setContentView(R.layout.activity_main);
           BottomNavigationView navView = findViewById(R.id.nav_view);
          // Passing each menu ID as a set of Ids because each
          // menu should be considered as top level destinations.
           AppBarConfiguration appBarConfiguration = new AppBarConfiguration.Builder(
                   R.id.navigation_home,
                   R. ----)
           .build();
           NavController navController = Navigation.findNavController(this, R.id.nav_host_fragment);
           NavigationUI.setupActionBarWithNavController(this, navController, appBarConfiguration);
           NavigationUI.setupWithNavController(navView, navController);
       }
   
       @Override
       public void onFragmentCreated(Fragment f) {
           if (f!=null){
               H.debug("fragment created listener: "+f.getId());
               f.setHasOptionsMenu(true);
           }else {
               H.debug("fragment created listener: NULL");
           }
       }
   }
   

And that is everything you need to do the job. Hop this help someone

val fragment: YourFragment? = yourNavHost.findFragment()

Note: findFragment extension function is located in androidx.fragment.app package, and it's generic function

create extension function on Fragment Manager

inline fun <reified T : Fragment> FragmentManager.findNavFragment(hostId: Int): T? {

    val navHostFragment = findFragmentById(hostId)

    return navHostFragment?.childFragmentManager?.fragments?.findLast {
        it is T
    } as T?
}

Now simply use it by giving id of the hosting fragment and get the specified fragment

    val myFragment: MyFragment? = supportFragmentManager.findNavFragment<MyFragment>(R.id.nav_host_id)

I combined Andrei Toaders answer and Mukul Bhardwajs answer with an OnBackStackChangedListener.

As an attribute:

private FooFragment fragment;

In my onCreate

NavHostFragment navHostFragment = (NavHostFragment) getSupportFragmentManager().findFragmentById(R.id.nav_host);
FragmentManager navHostManager = Objects.requireNonNull(navHostFragment).getChildFragmentManager();
FragmentManager.OnBackStackChangedListener listener = () -> {
        List<Fragment> frags = navHostManager.getFragments();
        if(!frags.isEmpty()) {
            fragment = (FooFragment) frags.get(0);
        }
};
navController.addOnDestinationChangedListener((controller, destination, arguments) -> {
        if(destination.getId()==R.id.FooFragment){
            navHostManager.addOnBackStackChangedListener(listener);
        } else {
            navHostManager.removeOnBackStackChangedListener(listener);
           fragment = null;
        }
});

This way i can get a fragment, which will be displayed later on. One even may be able to loop though frags and check multiple fragments with instanceof.

I need to do this to setup a bottom navigation view and I did it this way:

val navController = Navigation.findNavController(requireActivity(), R.id.nav_tabs_home)
        val bottomNavBar: BottomNavigationView = nav_content_view
        NavigationUI.setupWithNavController(bottomNavBar, navController)

The best way to achieve this is to register a fragment lifecycle callback.

As per the original question, if your NavHostFragment is defined as...

<fragment
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:id="@+id/nav_host"
        app:navGraph= "@navigation/nav_item"
        android:name="androidx.navigation.fragment.NavHostFragment"
        app:defaultNavHost= "true"
        />

Then in your main activity onCreate(..)...

nav_host.childFragmentManager.registerFragmentLifecycleCallbacks(
    object:FragmentManager.FragmentLifecycleCallbacks() {
        override fun onFragmentViewCreated(
            fm: FragmentManager, f: Fragment, v: View,
            savedInstanceState: Bundle?
        ) {
            // callback method always called whenever a
            // fragment is added, or, a back-press returns
            // to the start-destination
        }
    }
)

Other callback methods may be overridden to fit your requirements.

This solution will work in most situations Try this:

val mainFragment = fragmentManager?.primaryNavigationFragment?.parentFragment?.parentFragment as MainFragment

or this:

val mainFragment = fragmentManager?.primaryNavigationFragment?.parentFragment as MainFragment

This works for me

(navController.currentDestination as FragmentNavigator.Destination).className 

It will return canonicalName of your fragment

In your activity define a fragment object. And from each fragment call this method by passing fragment object, like So the static fragment object will be overridden by current showing fragment every time.

//method in MainActivity
private static Fragment fragment;

public void setFragment(Fragment fragment){
this.fragment = fragment;
}

//And from your fragment class, you can call
((<yourActivity in which fragment present>)getActivity()).setFragment(<your fragment object>);

//if you want to set it directly;
 ((<yourActivity in which fragment present>)getActivity()).fragment=<your fragment object>;

You can also set callback from fragment to activity, for a better approach and pass your current fragment object.