Reference MapView in SupportMapFragment

Question

I have a Fragment which Extends SupportMapFragment.

public class PlaceMapsFragment extends SupportMapFragment {
    private GoogleMap mMap;
    private LatLng mPosFija;

    public PlaceMapsFragment() {
        super();
    }

    public static PlaceMapsFragment newInstance(LatLng posicion) {
        PlaceMapsFragment frag = new PlaceMapsFragment();
        frag.mPosFija = posicion;
        return frag;
    }

    @Override
    public GoogleMap getMap() {
        // TODO Auto-generated method stub
        return super.getMap();
    }

    @Override
    public void onCreate(Bundle arg0) {
        // TODO Auto-generated method stub
        super.onCreate(arg0);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = super.onCreateView(inflater, container, savedInstanceState);
        //initMap();
        return view;
    }

    private void initMap() {
        UiSettings settings = getMap().getUiSettings();
        settings.setAllGesturesEnabled(false);
        settings.setMyLocationButtonEnabled(false);

        getMap().moveCamera(CameraUpdateFactory.newLatLngZoom(mPosFija, 16));
        getMap().addMarker(
                new MarkerOptions().position(mPosFija)
                        .icon(BitmapDescriptorFactory
                                .fromResource(R.drawable.marker)));
    }

}

Now i want to refernce the MapView that is automatically generated so that i can add my functionality to the map.

When i try to initMap(); i get NullPointerException

Error:

12-10 02:54:20.171: E/AndroidRuntime(4339): FATAL EXCEPTION: main
12-10 02:54:20.171: E/AndroidRuntime(4339): java.lang.NullPointerException
12-10 02:54:20.171: E/AndroidRuntime(4339):     at maps.ar.b.a(Unknown Source)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at maps.y.h.a(Unknown Source)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at maps.y.au.a(Unknown Source)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at maps.y.ae.moveCamera(Unknown Source)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.google.android.gms.maps.internal.IGoogleMapDelegate$Stub.onTransact(IGoogleMapDelegate.java:83)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.os.Binder.transact(Binder.java:297)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.google.android.gms.maps.internal.IGoogleMapDelegate$a$a.moveCamera(Unknown Source)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.google.android.gms.maps.GoogleMap.moveCamera(Unknown Source)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.m7.nomad.PlaceMapsFragment.initMap(PlaceMapsFragment.java:55)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.m7.nomad.PlaceMapsFragment.onCreateView(PlaceMapsFragment.java:46)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.support.v4.app.Fragment.performCreateView(Fragment.java:1460)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:911)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.support.v4.app.FragmentManagerImpl.moveToState(FragmentManager.java:1088)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.support.v4.app.BackStackRecord.run(BackStackRecord.java:682)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.support.v4.app.FragmentManagerImpl.execPendingActions(FragmentManager.java:1444)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.support.v4.app.FragmentManagerImpl.executePendingTransactions(FragmentManager.java:461)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.m7.nomad.PlaceActivity$TabManager.onTabChanged(PlaceActivity.java:153)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.widget.TabHost.invokeOnTabChangeListener(TabHost.java:379)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.widget.TabHost.setCurrentTab(TabHost.java:364)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.widget.TabHost$2.onTabSelectionChanged(TabHost.java:150)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.widget.TabWidget$TabClickListener.onClick(TabWidget.java:540)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.view.View.performClick(View.java:3591)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.view.View$PerformClick.run(View.java:14263)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.os.Handler.handleCallback(Handler.java:605)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.os.Handler.dispatchMessage(Handler.java:92)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.os.Looper.loop(Looper.java:137)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at android.app.ActivityThread.main(ActivityThread.java:4507)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at java.lang.reflect.Method.invokeNative(Native Method)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at java.lang.reflect.Method.invoke(Method.java:511)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:790)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:557)
12-10 02:54:20.171: E/AndroidRuntime(4339):     at dalvik.system.NativeStart.main(Native Method)

Answer 1

This is an expected behabiour.

You can call getMap() only after the Fragment has gone through onCreateView(), otherwise it will give you a null. You can also receive a null if the Google Play Services is not available.

In other words, call initMap() in onResume().

You can check more here.

Hope it helps!

Answer 2

I finally solved it, you dont have to override getMap() and you dont need the mMap variable, the GoogleMap is included in the class. Finally you need to call initMap() in onResume:

public class PlaceMapsFragment extends SupportMapFragment {
    private LatLng mPosFija = new LatLng(37.878901,-4.779396);

    public PlaceMapsFragment() {
        super();
    }

    public static PlaceMapsFragment newInstance(LatLng posicion) {
        PlaceMapsFragment frag = new PlaceMapsFragment();
        frag.mPosFija = posicion;
        return frag;
    }

   @Override
   public void onResume() {
    // TODO Auto-generated method stub
    super.onResume();
    initMap();
   }



    @Override
    public void onCreate(Bundle arg0) {
        // TODO Auto-generated method stub
        super.onCreate(arg0);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
            Bundle savedInstanceState) {
        View view = super.onCreateView(inflater, container, savedInstanceState);
        //initMap();
        return view;
    }

    private void initMap() {
        UiSettings settings = getMap().getUiSettings();
        settings.setAllGesturesEnabled(false);
        settings.setMyLocationButtonEnabled(false);

        getMap().moveCamera(CameraUpdateFactory.newLatLngZoom(mPosFija, 16));
        getMap().addMarker(
                new MarkerOptions().position(mPosFija)
                        .icon(BitmapDescriptorFactory
                                .fromResource(R.drawable.marker)));
    }

}

Hope it helps other people that are starting with the v2 of google maps api (like me :D).

Answer 3

The problem is in the onCreateView. You forgot to call super.onCreateView(). Check this