我正在尝试将数据写入Firebase，但是在调用savetoFirebase函数时，应用程序停止了。
我认为savetoFirebase函数存在某些错误，或者Firebase没有正确集成。
这是功能代码。
private void saveToFirebase() {
Location location = new Location("dummyprovider");
LatLng myCoordinates = new LatLng(location.getLatitude(), location.getLongitude());
Location mCurrentLocation = location;
Map mLocations = new HashMap();
Map mCoordinate = new HashMap();
mCoordinate.put("Latitude", mCurrentLocation.getLatitude());
mCoordinate.put("Longitude", mCurrentLocation.getLongitude());
mLocations.put("location", mCoordinate);
String url = "MY-FIREBASE-APP";
DatabaseReference myFirebaseRef = FirebaseDatabase.getInstance().getReferenceFromUrl(url);
myFirebaseRef.push().setValue(mLocations);
}
当加速度计的y轴更改时，我正在调用此函数，当此值更改时，还会发出蜂鸣声。 蜂鸣声仍在播放，但是该应用程序停止运行并显示弹出窗口表明该应用程序已停止。
以下是该应用的完整代码：
package com.example.hamzah.potholetrackingandmapping;
import android.Manifest;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.pm.PackageManager;
import android.location.Criteria;
import android.location.Location;
import android.location.LocationListener;
import android.location.LocationManager;
import android.media.MediaPlayer;
import android.os.Build;
import android.os.Bundle;
import android.provider.Settings;
import android.support.annotation.RequiresApi;
import android.support.v4.app.ActivityCompat;
import android.support.v4.app.FragmentActivity;
import android.util.Log;
import android.content.Context;
import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
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.Marker;
import com.google.android.gms.maps.model.MarkerOptions;
import com.google.firebase.FirebaseApp;
import com.google.firebase.database.DataSnapshot;
import com.google.firebase.database.DatabaseError;
import com.google.firebase.database.DatabaseReference;
import com.google.firebase.database.FirebaseDatabase;
import com.google.firebase.database.IgnoreExtraProperties;
import com.google.firebase.database.ValueEventListener;
import java.util.HashMap;
import java.util.Map;
public class MapsActivity extends FragmentActivity implements AccActivity, SensorEventListener {
final static int PERMISSION_ALL = 1;
private static final String TAG = "MainActivity";
final static String[] PERMISSIONS = {android.Manifest.permission.ACCESS_COARSE_LOCATION,
Manifest.permission.ACCESS_FINE_LOCATION};
public GoogleMap mMap;
public MarkerOptions mo;
public Marker marker;
public LocationManager locationManager;
private SensorManager mSensorManager;
private Sensor mAccelerometer;
private Sensor mAcc;
private float mLastX, mLastY, mLastZ;
private boolean mInitialized;
private MediaPlayer player;
@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);
mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
// Get the default sensor of specified type
mAccelerometer = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
mSensorManager.registerListener(this,mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
player = MediaPlayer.create(this, R.raw.beep);
mapFragment.getMapAsync(this);
locationManager = (LocationManager) getSystemService(LOCATION_SERVICE);
mo = new MarkerOptions().position(new LatLng(0, 0)).title("My Current Location");
if (Build.VERSION.SDK_INT >= 23 && !isPermissionGranted()) {
requestPermissions(PERMISSIONS, PERMISSION_ALL);
} else requestLocation();
if (!isLocationEnabled())
showAlert(1);
}
@Override
public void onMapReady(GoogleMap googleMap) {
mMap = googleMap;
marker = mMap.addMarker(mo);
}
@Override
public void onLocationChanged(Location location) {
LatLng myCoordinates = new LatLng(location.getLatitude(), location.getLongitude());
marker.setPosition(myCoordinates);
int zoom = 15;
mMap.moveCamera(CameraUpdateFactory.newLatLngZoom(myCoordinates, zoom));
}
@Override
public void onStatusChanged(String s, int i, Bundle bundle) {
}
@Override
public void onProviderEnabled(String s) {
}
@Override
public void onProviderDisabled(String s) {
}
private void requestLocation() {
Criteria criteria = new Criteria();
criteria.setAccuracy(Criteria.ACCURACY_COARSE);
criteria.setPowerRequirement(Criteria.POWER_HIGH);
String provider = locationManager.getBestProvider(criteria, true);
if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED && ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
// TODO: Consider calling
// ActivityCompat#requestPermissions
// here to request the missing permissions, and then overriding
// public void onRequestPermissionsResult(int requestCode, String[] permissions,
// int[] grantResults)
// to handle the case where the user grants the permission. See the documentation
// for ActivityCompat#requestPermissions for more details.
return;
}
locationManager.requestLocationUpdates(provider, 100, 10, this);
}
private boolean isLocationEnabled() {
return locationManager.isProviderEnabled(LocationManager.GPS_PROVIDER) ||
locationManager.isProviderEnabled(LocationManager.NETWORK_PROVIDER);
}
private boolean isPermissionGranted(){
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
if (checkSelfPermission(Manifest.permission.ACCESS_COARSE_LOCATION)
== PackageManager.PERMISSION_GRANTED || checkSelfPermission(Manifest.permission.ACCESS_FINE_LOCATION)
== PackageManager.PERMISSION_GRANTED) {
Log.v("myLog", "Permission is Granted");
return true;
}else {
Log.v("myLog", "Permission not Granted");
return false;
}
}
return false;
}
private void showAlert(final int status) {
String message, title, btnText;
if (status == 1) {
message = "Your Location Setting is set to 'Off'\nPlease Enable Location to " +
"use this app";
title = "Enable Location";
btnText = "Location Settings";
} else {
message = "Please Allow this app to access location!";
title = "Permission Access";
btnText = "Grant";
}
final AlertDialog.Builder dialog = new AlertDialog.Builder(this);
dialog.setCancelable(false);
dialog.setTitle(title)
.setMessage(message)
.setPositiveButton(btnText, new DialogInterface.OnClickListener() {
@RequiresApi(api = Build.VERSION_CODES.M)
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
if (status == 1) {
Intent myIntent = new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS);
startActivity(myIntent);
} else
requestPermissions(PERMISSIONS, PERMISSION_ALL);
}
})
.setNegativeButton("Cancel", new DialogInterface.OnClickListener() {
@Override
public void onClick(DialogInterface paramDialogInterface, int paramInt) {
finish();
}
});
dialog.show();
}
protected void onResume() {
super.onResume();
mSensorManager.registerListener(this,mAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
}
protected void onPause() {
super.onPause();
mSensorManager.unregisterListener(this);
}
@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
}
@Override
public void onSensorChanged(SensorEvent event) {
float x = event.values[0];
float y = event.values[1];
float z = event.values[2];
if (!mInitialized) {
mLastX = x;
mLastY = y;
mLastZ = z;
mInitialized = true;
} else {
float deltaY = y - mLastY;
float deltaZ = z - mLastZ;
mLastX = x;
mLastY = y;
mLastZ = z;
if (deltaY < -3) {
player.start();
Location location = new Location("dummyprovider");
LatLng myCoordinates = new LatLng(location.getLatitude(), location.getLongitude());
marker.setPosition(myCoordinates);
saveToFirebase();
}
}
}
private void saveToFirebase() {
Location location = new Location("dummyprovider");
LatLng myCoordinates = new LatLng(location.getLatitude(), location.getLongitude());
Location mCurrentLocation = location;
Map mLocations = new HashMap();
Map mCoordinate = new HashMap();
mCoordinate.put("Latitude", mCurrentLocation.getLatitude());
mCoordinate.put("Longitude", mCurrentLocation.getLongitude());
mLocations.put("location", mCoordinate);
String url = "MY-FIREBASE-APP";
DatabaseReference myFirebaseRef = FirebaseDatabase.getInstance().getReferenceFromUrl(url);
myFirebaseRef.push().setValue(mLocations);
}
}
我已经包含了依赖项com.google.firebase:firebase-core:16.0.6
该应用程序停止运行，甚至没有将数据写入Firebase。