I am using android studio 3.0 on that when i run App it crashes when i run it on the real device once i click buttonGo . in the code it shows me in yellow line Response.body.toString is reduntant and App crashes and Logcat is indicating me to refer the line when it shows it is reduntant . My logcat is below
Attempt to invoke virtual method 'java.lang.String java.lang.String.toString()' on a null object reference
at com.clone.uber.uberclone.Welcome$4.onResponse(Welcome.java:240)
at retrofit2.ExecutorCallAdapterFactory$ExecutorCallbackCall$1$1.run(ExecutorCallAdapterFactory.java:70)
at android.os.Handler.handleCallback(Handler.java:739)
at android.os.Handler.dispatchMessage(Handler.java:95)
at android.os.Looper.loop(Looper.java:135)
at android.app.ActivityThread.main(ActivityThread.java:5912)
at java.lang.reflect.Method.invoke(Native Method)
at java.lang.reflect.Method.invoke(Method.java:372)
at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:1405)
at com.android.internal.os.ZygoteInit.main
My Java code
package com.clone.uber.uberclone;
import android.*;
import android.Manifest;
import android.animation.ValueAnimator;
import android.content.pm.PackageManager;
import android.graphics.Color;
import android.location.Location;
import android.os.Handler;
import android.os.SystemClock;
import android.support.annotation.NonNull;
import android.support.annotation.Nullable;
import android.support.design.widget.Snackbar;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.View;
import android.view.animation.Interpolator;
import android.view.animation.LinearInterpolator;
import android.widget.Button;
import android.widget.EditText;
import android.widget.Toast;
import com.clone.uber.uberclone.Common.Common;
import com.clone.uber.uberclone.Remote.IGoogleAPI;
import com.firebase.geofire.GeoFire;
import com.firebase.geofire.GeoLocation;
import com.github.glomadrian.materialanimatedswitch.MaterialAnimatedSwitch;
import com.google.android.gms.common.ConnectionResult;
import com.google.android.gms.common.GooglePlayServicesUtil;
import com.google.android.gms.common.api.GoogleApiClient;
import com.google.android.gms.location.LocationListener;
import com.google.android.gms.location.LocationRequest;
import com.google.android.gms.location.LocationServices;
import com.google.android.gms.maps.CameraUpdate;
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.BitmapDescriptorFactory;
import com.google.android.gms.maps.model.CameraPosition;
import com.google.android.gms.maps.model.JointType;
import com.google.android.gms.maps.model.LatLng;
import com.google.android.gms.maps.model.LatLngBounds;
import com.google.android.gms.maps.model.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.android.gms.maps.model.Polyline;
import com.google.android.gms.maps.model.PolylineOptions;
import com.google.android.gms.maps.model.SquareCap;
import com.google.firebase.auth.FirebaseAuth;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.List;
import retrofit2.Call;
import retrofit2.Callback;
import retrofit2.Response;
public class Welcome extends FragmentActivity implements OnMapReadyCallback,
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener
{
private GoogleMap mMap;
//play services
private static final int MY_PERMISSION_REQUEST_CODE= 7000;
private static final int PLAY_SERVICE_RES_REQUEST=7001;
private LocationRequest mLocationRequest;
private GoogleApiClient mGoogleApiClient;
private Location mLastLocation;
private static int UPDATE_INTERVAL= 5000;
private static int FASTEST_INTERVAL=3000;
private static int DISPLACEMENT= 10;
DatabaseReference drivers;
GeoFire geoFire;
Marker mCurrent;
MaterialAnimatedSwitch location_switch;
SupportMapFragment mapFragment;
//car animation
private List<LatLng> polyLineList;
private Marker carMarker;
private float v;
private double lat,lng;
private Handler handler;
private LatLng startPosition,endPosition,currentPosition;
private int index,next;
private Button btnGo;
private EditText edtPlace;
private String destination;
private PolylineOptions polylineOptions, blackPolylineOptions;
private Polyline blackPolyline,greyPolyline;
private IGoogleAPI mService;
Runnable drawPathRunnable = new Runnable() {
@Override
public void run() {
if (index<polyLineList.size()-1)
{
index++;
next= index+1;
}
if (index<polyLineList.size()-1)
{
startPosition = polyLineList.get(index);
endPosition= polyLineList.get(next);
}
ValueAnimator valueAnimator= ValueAnimator.ofFloat(0,1);
valueAnimator.setDuration(3000);
valueAnimator.setInterpolator(new LinearInterpolator());
valueAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator valueAnimator) {
v =valueAnimator.getAnimatedFraction();
lng = v*endPosition.longitude+(1-v)*startPosition.longitude;
lat = v*endPosition.latitude+(1-v)*startPosition.latitude;
LatLng newPos= new LatLng(lat,lng);
carMarker.setPosition(newPos);
carMarker.setAnchor(0.5f,0.5f);
carMarker.setRotation(getBearing(startPosition,newPos));
mMap.moveCamera(CameraUpdateFactory.newCameraPosition(
new CameraPosition.Builder()
.target(newPos)
.zoom(15.5f)
.build()
));
}
});
valueAnimator.start();
handler.postDelayed(this,3000);
}
};
private float getBearing(LatLng startPosition, LatLng endPosition) {
double lat = Math.abs(startPosition.latitude - endPosition.latitude);
double lng = Math.abs(startPosition.longitude - endPosition.longitude);
if (startPosition.latitude < endPosition.latitude && startPosition.longitude < endPosition.longitude)
return (float) (Math.toDegrees(Math.atan(lng/lat)));
else if (startPosition.latitude >= endPosition.latitude && startPosition.longitude < endPosition.longitude)
return (float) ((90-Math.toDegrees(Math.atan(lng/lat)))+90);
else if (startPosition.latitude >= endPosition.latitude && startPosition.longitude >= endPosition.longitude)
return (float) (Math.toDegrees(Math.atan(lng/lat))+180);
else if (startPosition.latitude < endPosition.latitude && startPosition.longitude >= endPosition.longitude)
return (float) ((90-Math.toDegrees(Math.atan(lng/lat)))+270);
return -1;
}
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_welcome);
// Obtain the SupportMapFragment and get notified when the map is ready to be used.
mapFragment = (SupportMapFragment) getSupportFragmentManager()
.findFragmentById(R.id.map);
mapFragment.getMapAsync(this);
//init view
location_switch =(MaterialAnimatedSwitch)findViewById(R.id.location_switch);
location_switch.setOnCheckedChangeListener(new MaterialAnimatedSwitch.OnCheckedChangeListener() {
@Override
public void onCheckedChanged(boolean isOnline) {
if (isOnline)
{
startLocationUpdates();
displayLocation();
Snackbar.make(mapFragment.getView(),"you are Online",Snackbar.LENGTH_SHORT).show();
}
else
{
stopLocationUpdates();
mCurrent.remove();
mMap.clear();
handler.removeCallbacks(drawPathRunnable);
Snackbar.make(mapFragment.getView(),"you are Offline",Snackbar.LENGTH_SHORT).show();
}
}
});
polyLineList =new ArrayList<>();
btnGo=(Button)findViewById(R.id.btnGo);
edtPlace=(EditText)findViewById(R.id.edtPlace);
btnGo.setOnClickListener(new View.OnClickListener() {
@Override
public void onClick(View view) {
destination= edtPlace.getText().toString();
destination = destination.replace(" ","+"); //replsce space with + for fetch data
Log.d("WAHDAT",destination);
getDirection();
}
});
//geo fire
drivers = FirebaseDatabase.getInstance().getReference("Drivers");
geoFire=new GeoFire(drivers);
setUpLocation();
mService= Common.getGoogleAPI();
}
private void getDirection() {
currentPosition=new LatLng(mLastLocation.getLatitude(),mLastLocation.getLongitude());
String requestApi =null;
try{
requestApi="https://maps.googleapis.com/maps/api/direction/json?"+
"mode=driving&"+
"transit_routing_preference=less_driving&"+
"origin="+currentPosition.latitude+","+currentPosition.longitude+"&"+
"destination="+destination+"&"+
"key="+getResources().getString(R.string.google_direction_api);
Log.d("WAHDAT",requestApi); //print url for debug
mService.getPath(requestApi)
.enqueue(new Callback<String>() {
@Override
public void onResponse(Call<String> call, Response<String> response) {
try {
JSONObject jsonObject=new JSONObject(response.body().toString());
JSONArray jsonArray=jsonObject.getJSONArray("routes");
for (int i=0;i<jsonArray.length();i++)
{
JSONObject route=jsonArray.getJSONObject(i);
JSONObject poly =route.getJSONObject("overview_polyline");
String polyline=poly.getString("points");
polyLineList=decodePoly(polyline);
}
//adjusting bounds
LatLngBounds.Builder builder=new LatLngBounds.Builder();
for (LatLng latLng:polyLineList)
builder.include(latLng);
LatLngBounds bounds=builder.build();
CameraUpdate mCameraUpdate =CameraUpdateFactory.newLatLngBounds(bounds,2);
mMap.animateCamera(mCameraUpdate);
polylineOptions = new PolylineOptions();
polylineOptions.color(Color.GRAY);
polylineOptions.width(5);
polylineOptions.startCap(new SquareCap());
polylineOptions.endCap(new SquareCap());
polylineOptions.jointType(JointType.ROUND);
polylineOptions.addAll(polyLineList);
greyPolyline = mMap.addPolyline(polylineOptions);
blackPolylineOptions = new PolylineOptions();
blackPolylineOptions.color(Color.GRAY);
blackPolylineOptions.width(5);
blackPolylineOptions.startCap(new SquareCap());
blackPolylineOptions.endCap(new SquareCap());
blackPolylineOptions.jointType(JointType.ROUND);
blackPolyline = mMap.addPolyline(blackPolylineOptions);
mMap.addMarker(new MarkerOptions().position(polyLineList.get(polyLineList.size()-1))
.title("PickUp location"));
//Animation
ValueAnimator polyLineAnimator =ValueAnimator.ofInt(0,100);
polyLineAnimator.setDuration(2000);
polyLineAnimator.setInterpolator(new LinearInterpolator());
polyLineAnimator.addUpdateListener(new ValueAnimator.AnimatorUpdateListener() {
@Override
public void onAnimationUpdate(ValueAnimator valueAnimator) {
List<LatLng> points = greyPolyline.getPoints();
int percentValue=(int)valueAnimator.getAnimatedValue();
int size=points.size();
int newPoints = (int)(size * (percentValue/100.0f));
List<LatLng> p=points.subList(0,newPoints);
blackPolyline.setPoints(p);
}
});
polyLineAnimator.start();
carMarker = mMap.addMarker(new MarkerOptions().position(currentPosition)
.flat(true)
.icon(BitmapDescriptorFactory.fromResource(R.drawable.car)));
handler = new Handler();
index=-1;
next=1;
handler.postDelayed(drawPathRunnable,3000);
} catch (JSONException e) {
e.printStackTrace();
}
}
@Override
public void onFailure(Call<String> call, Throwable t) {
Toast.makeText(Welcome.this,""+t.getMessage(),Toast.LENGTH_SHORT).show();
}
});
}catch (Exception e)
{
e.printStackTrace();
}
}
private List decodePoly(String encoded) {
List poly = new ArrayList();
int index = 0, len = encoded.length();
int lat = 0, lng = 0;
while (index < len) {
int b, shift = 0, result = 0;
do {
b = encoded.charAt(index++) - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
int dlat = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
lat += dlat;
shift = 0;
result = 0;
do {
b = encoded.charAt(index++) - 63;
result |= (b & 0x1f) << shift;
shift += 5;
} while (b >= 0x20);
int dlng = ((result & 1) != 0 ? ~(result >> 1) : (result >> 1));
lng += dlng;
LatLng p = new LatLng((((double) lat / 1E5)),
(((double) lng / 1E5)));
poly.add(p);
}
return poly;
}
//we request runtime permission, we need override onrequestpermissionresult method
@Override
public void onRequestPermissionsResult(int requestCode, @NonNull String[] permissions, @NonNull int[] grantResults) {
switch (requestCode)
{
case MY_PERMISSION_REQUEST_CODE:
if (grantResults.length >0 && grantResults[0] ==PackageManager.PERMISSION_GRANTED)
{
if (checkPlayServices())
{
buildGoogleApiClient();
createLocationRequest();
if (location_switch.isChecked())
displayLocation();
}
}
}
}
private void setUpLocation() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
{
//request runtime permission
ActivityCompat.requestPermissions(this,new String[]{
Manifest.permission.ACCESS_COARSE_LOCATION,
Manifest.permission.ACCESS_FINE_LOCATION
},MY_PERMISSION_REQUEST_CODE);
}
else
{
if (checkPlayServices())
{
buildGoogleApiClient();
createLocationRequest();
if (location_switch.isChecked())
displayLocation();
}
}
}
private void createLocationRequest() {
mLocationRequest =new LocationRequest();
mLocationRequest.setInterval(UPDATE_INTERVAL);
mLocationRequest.setFastestInterval(FASTEST_INTERVAL);
mLocationRequest.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY);
mLocationRequest.setSmallestDisplacement(DISPLACEMENT);
}
private void buildGoogleApiClient() {
mGoogleApiClient =new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
mGoogleApiClient.connect();
}
private boolean checkPlayServices() {
int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
if (resultCode != ConnectionResult.SUCCESS) {
if (GooglePlayServicesUtil.isUserRecoverableError(resultCode))
GooglePlayServicesUtil.getErrorDialog(resultCode, this, PLAY_SERVICE_RES_REQUEST).show();
else {
Toast.makeText(this, "This device is not supported", Toast.LENGTH_SHORT).show();
finish();
}
return false;
}
return true;
}
private void stopLocationUpdates() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
{
return;
}
LocationServices.FusedLocationApi.removeLocationUpdates(mGoogleApiClient,this);
}
private void displayLocation() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
{
return;
}
mLastLocation= LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
if (mLastLocation !=null)
{
if (location_switch.isChecked())
{
final double latitude= mLastLocation.getLatitude();
final double longitude=mLastLocation.getLongitude();
//update to firebase
geoFire.setLocation(FirebaseAuth.getInstance().getCurrentUser().getUid(), new GeoLocation(latitude, longitude), new GeoFire.CompletionListener() {
@Override
public void onComplete(String key, DatabaseError error) {
//add marker
if (mCurrent !=null)
mCurrent.remove();//remove marker already
mCurrent = mMap.addMarker(new MarkerOptions()
.position(new LatLng(latitude,longitude))
.title("Your Location"));
//
// //move camera to this position
mMap.animateCamera(CameraUpdateFactory.newLatLngZoom(new LatLng(latitude,longitude),15.0f));
//
}
});
}
}
else
{
Log.d("ERROR","Cannot get your Location");
}
}
private void rotateMarker(final Marker mCurrent, final float i, GoogleMap mMap) {
final Handler handler=new Handler();
final long start= SystemClock.uptimeMillis();
final float startRotation = mCurrent.getRotation();
final long duration = 1500;
final Interpolator interpolator=new LinearInterpolator();
handler.post(new Runnable() {
@Override
public void run() {
long elapsed=SystemClock.uptimeMillis() - start;
float t= interpolator.getInterpolation((float)elapsed/duration);
float rot= t*i+(1-t)*startRotation;
mCurrent.setRotation(-rot >180?rot/2:rot);
if (t<1.0)
{
handler.postDelayed(this,16);
}
}
});
}
private void startLocationUpdates() {
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED)
{
return;
}
LocationServices.FusedLocationApi.requestLocationUpdates(mGoogleApiClient,mLocationRequest,this);
}
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
mMap.setMapType(GoogleMap.MAP_TYPE_NORMAL);
mMap.setTrafficEnabled(false);
mMap.setIndoorEnabled(false);
mMap.setBuildingsEnabled(false);
mMap.getUiSettings().setZoomControlsEnabled(true);
}
@Override
public void onConnected(@Nullable Bundle bundle) {
displayLocation();
startLocationUpdates();
}
@Override
public void onConnectionSuspended(int i) {
mGoogleApiClient.connect();
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
}
@Override
public void onLocationChanged(Location location) {
mLastLocation= location;
displayLocation();
}
}