How to use SupportMapFragment inside a Fragment?

Question

I know that there has been an issue in using a nested fragment. But my application was designed to run on fragments and if i will be using activity for the map, my casting functions will have error.

I would like to ask help from you on how to achieve this. I've been searching in the internet but i couldn't find best solution.

I've tried this code:

private void setUpMapIfNeeded() {
    // Do a null check to confirm that we have not already instantiated the map.
    if (mMap == null) {
        // Try to obtain the map from the SupportMapFragment.
        mMap = ((SupportMapFragment) myFragmentActivity.getSupportFragmentManager().findFragmentById(R.id.map_con))
                .getMap();
        // Check if we were successful in obtaining the map.
        if (mMap != null) {
            mMap.setMyLocationEnabled(true);
        }
    }
}

this would give me duplicate error because of R.id.map_con is a fragment inside my fragment.

So I look for a work around, this time, R.id.map_con is a frame layout and in the run time I created the SupportMapFragment to it.

SupportMapFragment mSupportMapFragment = new SupportMapFragment();
    myFragmentActivity.getSupportFragmentManager().beginTransaction()
            .replace(R.id.map_con, mSupportMapFragment).commit();

though this does not give me a duplicate every time a close and open the fragment. but my error is that mSupportMapFragment.getMap is always null., I don't get it why its null?.

mMap = mSupportMapFragment.newInstance().getMap();
        if (mMap != null){
            Log.e("ReportFragment","mMap is not empty");
        }else{
            Log.e("ReportFragment","mMap is empty");
        }

I would really appreciate any inputs from you guys, or do you have another work around but still in this process, i.e Fragment inside fragment

Thanks

chkm8

Answer 1

I just met my luck, while making this post,I found what Im looking for.

I have used this:

 @Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
    View v = inflater.inflate(R.layout.fragment_location, container, false);
    mMapFragment = new SupportMapFragment() {
        @Override
        public void onActivityCreated(Bundle savedInstanceState) {
            super.onActivityCreated(savedInstanceState);
            mMap = mMapFragment.getMap();
            if (mMap != null) {
                setupMap();
            }
        }
    };
    getChildFragmentManager().beginTransaction().add(R.id.framelayout_location_container, mMapFragment).commit();
return v;   
}

Credit to this Old post

Answer 2

getMap() is deprecated

The code should be something like this in a Fragment:

@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {

    View v = inflater.inflate(R.layout.fragment_location, container, false);

    mMapFragment = (SupportMapFragment) getChildFragmentManager().findFragmentById(R.id.map);
    mMapFragment.getMapAsync(this);

    return v;   
}

Answer 3

I have used it in the given manner and it's working fine.

It's also working with getChildFragmentManager()

MapyFragment

public class MapyFragment extends Fragment implements OnMapReadyCallback {

    private Context mContext;
    private SupportMapFragment supportMapFragment;
    private GoogleMap map;
    private MarkerOptions currentPositionMarker = null;
    private Marker currentLocationMarker;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
        mContext = getActivity();
        return inflater.inflate(R.layout.fragment_mapy, container, false);
    }

    @Override
    public void onActivityCreated(@Nullable Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);

        mContext = getActivity();

        FragmentManager fm = getActivity().getSupportFragmentManager();/// getChildFragmentManager();
        supportMapFragment = (SupportMapFragment) fm.findFragmentById(R.id.map_container);
        if (supportMapFragment == null) {
            supportMapFragment = SupportMapFragment.newInstance();
            fm.beginTransaction().replace(R.id.map_container, supportMapFragment).commit();
        }
        supportMapFragment.getMapAsync(this);
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        map = googleMap;
        if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
                ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            return;
        }
        map.setMyLocationEnabled(true);
        map.animateCamera(CameraUpdateFactory.zoomTo(15));
        /*map.setOnMapLongClickListener(MapyFragment.this);
        map.setOnMapClickListener(MapFragment.this);*/
    }

    public void updateCurrentLocationMarker(Location currentLatLng){

        if(map != null){

            LatLng latLng = new LatLng(currentLatLng.getLatitude(),currentLatLng.getLongitude());
            if(currentPositionMarker == null){
                currentPositionMarker = new MarkerOptions();

                currentPositionMarker.position(latLng)
                        .title("My Location").
                        icon(BitmapDescriptorFactory.fromResource(R.drawable.start_blue));
                currentLocationMarker = map.addMarker(currentPositionMarker);
            }

            if(currentLocationMarker != null)
                currentLocationMarker.setPosition(latLng);

            ///currentPositionMarker.position(latLng);
            map.moveCamera(CameraUpdateFactory.newLatLng(latLng));
        }
    }
}

and fragment_mapy.xml

<?xml version="1.0" encoding="utf-8"?>
<fragment xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:map="http://schemas.android.com/apk/res-auto"
    android:id="@+id/map_container"
    class="com.google.android.gms.maps.SupportMapFragment"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    map:uiZoomControls="true" />

Answer 4

In kotlin it could be done as follows:

class NameFragment: Fragment(){
    // other code ...
    private lateinit var googleMapsFragment: SupportMapFragment

    override fun onCreateView(
            inflater: LayoutInflater, container: ViewGroup?,
            savedInstanceState: Bundle?
    ): View {
         googleMapsFragment = childFragmentManager.findFragmentById(R.id.map_fragment) as SupportMapFragment
        // other code ...
    }
}