Android -boolean com.google.android.gms.common.api.GoogleApiClient.isConnected()' on a null object reference

Question

I'm getting error on my fragment class which is state that

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean com.google.android.gms.common.api.GoogleApiClient.isConnected()' on a null object reference at fragment.HomeFragment.onResume

This is my partial code on HomeFragment

private GoogleApiClient mGoogleApiClient;


@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    if (getArguments() != null) {
        mCurrentLocation = savedInstanceState.getParcelable(KEY_LOCATION);
        mCameraPosition = 
savedInstanceState.getParcelable(KEY_CAMERA_POSITION);
    }        buildGoogleApiClient();
}

@Override
public void onResume() {
    super.onResume();
    if (mGoogleApiClient.isConnected()) {
        getDeviceLocation();
    }
    updateMarkers();
}

    private synchronized void buildGoogleApiClient() {
    GoogleApiClient.Builder builder = new GoogleApiClient.Builder(getActivity());
    mGoogleApiClient = builder.build();
    //builder.enableAutoManage(this /* FragmentActivity */, this /* OnConnectionFailedListener */);
    builder.addConnectionCallbacks(this);
    builder.addApi(LocationServices.API);
    builder.addApi(Places.GEO_DATA_API);
    builder.addApi(Places.PLACE_DETECTION_API);
    builder.build();
    createLocationRequest();
}

I also implemented

1. OnMapReadyCallback
2. GoogleApiClient.ConnectionCallbacks
3. GoogleApiClient.OnConnectionFailedListener
4. LocationListener
5. DirectionFinderListener

Can someone help me with this?

Answer 1

You need to keep a reference to the instance of GoogleApiClient you're building. So it should be:

private void buildGoogleApiClient() {
    mGoogleApiClient = new GoogleApiClient.Builder(getActivity())
        .addConnectionCallbacks(this)
        .addApi(LocationServices.API)
        .addApi(Places.GEO_DATA_API)
        .addApi(Places.PLACE_DETECTION_API)
        .build();
    createLocationRequest();
}