GetSupportFragmentManager (). findFragmentById returns null for google maps in fragment in android?

Question

I have a problem with Google Maps i.e. getSupportFragmentManager (). findFragmentById always returns null. Do you have an idea how to solve this?

Here is the code:

fragment_map.xml: <FrameLayout xmlns:android="http://schemas.android.com/apk/res/android" xmlns:tools="http://schemas.android.com/tools" android:layout_width="match_parent" android:layout_height="match_parent" tools:context="com.myapp.something.MapFragment"> <fragment android:id="@+id/map" android:layout_width="match_parent" android:layout_height="match_parent" class="com.google.android.gms.maps.SupportMapFragment" /> </FrameLayout> 

MapsFragment.java:

 public class MapFragment extends Fragment implements OnMapReadyCallback, android.location.LocationListener public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); SupportMapFragment mapFragment = (SupportMapFragment) this.getActivity().getSupportFragmentManager().findFragmentById(R.id.map); mapFragment.getMapAsync(this); ... 

I have Google Maps in action and it works with code:

 SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager() .findFragmentById(R.id.map); mapFragment.getMapAsync(this); 

I am trying to reuse this in a fragment because I need cards in the fragment and not in activity, but it does not work.

I tried:

• calling this code in onCreateView function
• SupportMapFragment mapFragment = (SupportMapFragment) getFragmentManager().findFragmentById(R.id.map);
• GoogleMap mGoogleMap = ((SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map)).getMap(); Deprecated and the application crashes
• SupportMapFragment mapFragment = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map); and similar options, but in all cases I get null for mapFragment.

Do you know how I can solve this problem?

Answer 1

The problem is that you are trying to use the Activity FragmentManager, and you should use the Fragment child FragmentManager.

Remove the onCreate() override in the Snippet and add onCreateView() Override, where you getMapAsync() layout and call getMapAsync() :

 @Override public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) { View rootView = inflater.inflate(R.layout.fragment_map, container, false); SupportMapFragment mapFragment = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map); mapFragment.getMapAsync(this); return rootView; }