I'm very new to anything about Android studio and Java. I try to make an map App with some points of interest. The points is a geojson file. I read the example of google and the explanation in their web site (Google Maps Android GeoJSON Utility) but I have some errors in my code.The first error is about getmMap method, (error:cannot find symbol method getnMap()). The second which I find a solution is about the file It didn't need the extension (geojson). I make a folder in rs with name raw and add the geojson file inside.
Full code of MapsActivity.java
package com.example.vassilis.goldman_find_atm;
import android.Manifest;
import android.content.pm.PackageManager;
import android.os.Build;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import com.google.android.gms.maps.CameraUpdateFactory;
import com.google.android.gms.maps.GoogleMap;
import com.google.android.gms.maps.OnMapReadyCallback;
import com.google.android.gms.maps.SupportMapFragment;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.maps.android.data.geojson.GeoJsonLayer;
public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {
    private static final int MY_REQUEST_INT = 177;
    private GoogleMap mMap;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_maps);
        // Obtain the SupportMapFragment and get notified when the map is ready to be used.
        SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                .findFragmentById(R.id.map);
        mapFragment.getMapAsync(this);
    }
    /**
     * Manipulates the map once available.
     * This callback is triggered when the map is ready to be used.
     * This is where we can add markers or lines, add listeners or move the camera. In this case,
     * we just add a marker near Sydney, Australia.
     * If Google Play services is not installed on the device, the user will be prompted to install
     * it inside the SupportMapFragment. This method will only be triggered once the user has
     * installed Google Play services and returned to the app.
     */
    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;
        //Enable Current Location:
        //Here We want to check the permission of Location - GPS
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            // TODO: Consider calling
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M){
                requestPermissions(new String[]{Manifest.permission.ACCESS_COARSE_LOCATION,
                        Manifest.permission.ACCESS_FINE_LOCATION},MY_REQUEST_INT);
            }
            return;
        }else {
            //Here the code of Grand Permission
            mMap.setMyLocationEnabled(true);
        }
        // Add a marker in Sydney and move the camera
        /*LatLng sydney = new LatLng(-34, 151);
        mMap.addMarker(new MarkerOptions().position(sydney).title("Marker in Sydney"));
        mMap.moveCamera(CameraUpdateFactory.newLatLng(sydney));*/
        GeoJsonLayer layer = new GeoJsonLayer(getmMap(), R.raw.nbg_bank.geojson ,
                getApplicationContext());
        layer.addLayerToMap();
    }
}
error: cnnot find symbol method getmMap()
I change getmMap() to mMap and the system :Surround with try/catch. I change it and the code change to. The building of the code finish without problems but in map I didn't see the points.
From
GeoJsonLayer layer = new GeoJsonLayer(mMap, R.raw.nbg_bank,
                getApplicationContext());
        layer.addLayerToMap();
To
GeoJsonLayer layer = null;
        try {
            layer = new GeoJsonLayer(mMap, R.raw.nbg_bank,
                    getApplicationContext());
        } catch (IOException e) {
            e.printStackTrace();
        } catch (JSONException e) {
            e.printStackTrace();
        }
        layer.addLayerToMap();


 
    