如何在 Geofence android 中添加后台服务

Question

我正在尝试创建一个带有后台服务的地理围栏以进行监控。地理围栏创建成功并在应用程序活动打开但关闭应用程序地理围栏时工作。我现在该怎么办。我的代码是：

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback,
    GoogleApiClient.ConnectionCallbacks,
    GoogleApiClient.OnConnectionFailedListener,
    LocationListener {


@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);

    ref = FirebaseDatabase.getInstance().getReference("MyLocation");
    geoFire = new GeoFire(ref);
    mVerticalSeekBar = (VerticalSeekBar)findViewById(R.id.verticalSeekBar);

    setUpdateLocation();

}

@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 (checkPlayService()) {
                    buildGoogleApiClient();
                    createLocationRequest();
                    displayLocation();
                }
            }
            break;
    }
}

private void setUpdateLocation() {
    if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
            ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
        ActivityCompat.requestPermissions(this, new String[]{
                Manifest.permission.ACCESS_COARSE_LOCATION,
                Manifest.permission.ACCESS_FINE_LOCATION
        }, MY_PERMISSION_REQUEST_CODE);
    } else {
        if (checkPlayService()) {
            buildGoogleApiClient();
            createLocationRequest();
            displayLocation();
        }
    }
}

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;
    }

    mLastLocaiton = LocationServices.FusedLocationApi.getLastLocation(mGoogleApiClient);
    if (mLastLocaiton != null) {
        final double latitude = mLastLocaiton.getLatitude();
        final double longitude = mLastLocaiton.getLongitude();

        geoFire.setLocation("You", new GeoLocation(latitude, longitude), new GeoFire.CompletionListener() {
            @Override
            public void onComplete(String key, DatabaseError error) {
                if (mCurrent != null)
                    mCurrent.remove();
                mCurrent = mMap.addMarker(new MarkerOptions()
                        .position(new LatLng(latitude, longitude))
                        .title("You"));
                LatLng coordinate = new LatLng(latitude, longitude);
                CameraUpdate yourLocation = CameraUpdateFactory.newLatLngZoom(coordinate, 12);
                mMap.animateCamera(yourLocation);
            }
        });

        Log.d("MRF", String.format("Your last location was chaged: %f / %f", latitude, longitude));
    } else {
        Log.d("MRF", "Can not get your location.");
    }
}

private void createLocationRequest() {
    mLocationRequest = new LocationRequest();
    mLocationRequest.setInterval(UPDATE_INTERVAL);
    mLocationRequest.setFastestInterval(FATEST_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 checkPlayService() {
    GoogleApiAvailability googleAPI = GoogleApiAvailability.getInstance();
    int result = googleAPI.isGooglePlayServicesAvailable(this);
    if (result != ConnectionResult.SUCCESS) {
        if (googleAPI.isUserResolvableError(result)) {
            googleAPI.getErrorDialog(this, result, PLAY_SERVICE_RESULATION_REQUEST).show();
        } else {
            Toast.makeText(this, "This Device is not supported.", Toast.LENGTH_SHORT).show();
        }
        return false;
    }

    return true;
}

@Override
public void onMapReady(GoogleMap googleMap) {
    mMap = googleMap;

    LatLng dangerous_area = new LatLng(23.7424236, 90.3942189);
    mMap.addCircle(new CircleOptions()
            .center(dangerous_area)
            .radius(100)
            .strokeColor(Color.BLUE)
            .fillColor(0x220000FF)
            .strokeWidth(5.0f));

    //add GeoQuery here
    GeoQuery geoQuery = geoFire.queryAtLocation(new GeoLocation(dangerous_area.latitude, dangerous_area.longitude), 0.1f);
    geoQuery.addGeoQueryEventListener(new GeoQueryEventListener() {
        @Override
        public void onKeyEntered(String key, GeoLocation location) {
            sendNotification("MRF", String.format("%s entered the dangerous area",key));
        }

        @Override
        public void onKeyExited(String key) {
            sendNotification("MRF", String.format("%s exit the dangerous area",key));
        }

        @Override
        public void onKeyMoved(String key, GeoLocation location) {
            Log.d("MOVE", String.format("%s move within the dangerous area [%f/%f]", key, location.latitude, location.longitude));
        }

        @Override
        public void onGeoQueryReady() {

        }

        @Override
        public void onGeoQueryError(DatabaseError error) {
            Log.d("ERROR", ""+error);
        }
    });
}

private void sendNotification(String title, String content) {
    Notification.Builder builder = new Notification.Builder(this)
            .setSmallIcon(R.mipmap.ic_launcher)
            .setContentTitle(title)
            .setContentText(content);

    NotificationManager manager = (NotificationManager)this.getSystemService(Context.NOTIFICATION_SERVICE);
    Intent intent = new Intent(this, MapsActivity.class);
    PendingIntent contentIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_IMMUTABLE);
    builder.setContentIntent(contentIntent);
    Notification notification = builder.build();
    notification.flags |= Notification.FLAG_AUTO_CANCEL;
    notification.defaults |= Notification.DEFAULT_SOUND;
    manager.notify(new Random().nextInt(), notification);
}

@Override
public void onConnected(@Nullable Bundle bundle) {
    displayLocation();
    startLocationUpdate();
}

private void startLocationUpdate() {
    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 onConnectionSuspended(int i) {
    mGoogleApiClient.connect();
}

@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

}

@Override
public void onLocationChanged(Location location) {
    mLastLocaiton = location;
    displayLocation();
}

github链接为：https://github.com/Farhad2015/Geofence-GeoFire/blob/master/app/src/main/java/com/mahmud/geotesting/MapsActivity.java

请帮我创建一个后台服务，用于从后台监控地理围栏。

Answer 1

在 Android Oreo 中，您无法将长时间运行的服务创建为后台服务。所以你必须创建一个前台服务，该服务必须绑定到当前的Activity

另一个问题是位置更新。当您在服务中使用geoQuery 时，您还必须在服务中更新位置。当位置更新触发时，您必须将此更新传递给活动，然后只有 UI 可以更新。在我的解决方案中，我使用一个界面来更新 UI。您还可以使用广播侦听器。

当您创建服务并将其绑定到活动时，您可以在服务中使用地理围栏

 public void startService(LatLng latLng, double radius) {
        if (!isServiceRunning) {
            isServiceRunning = true;

        } else {
            Log.e(TAG, "startTimer request for an already running timer");

        }
        if (geoQuery!=null){
            geoQuery.removeAllListeners();
        }
        geoQuery = geoFire.queryAtLocation(new GeoLocation(latLng.latitude, latLng.longitude), 2f);
        geoQuery.addGeoQueryEventListener(new GeoQueryEventListener() {
            @Override
            public void onKeyEntered(String key, GeoLocation location) {
                sendNotification("MRF", String.format("%s entered the dangerous area", key));
            }

            @Override
            public void onKeyExited(String key) {
                sendNotification("MRF", String.format("%s exit the dangerous area", key));
            }

            @Override
            public void onKeyMoved(String key, GeoLocation location) {
                Log.d("MOVE", String.format("%s move within the dangerous area [%f/%f]", key, location.latitude, location.longitude));
            }

            @Override
            public void onGeoQueryReady() {

            }

            @Override
            public void onGeoQueryError(DatabaseError error) {
                Log.d("ERROR", "" + error);
            }
        });
    }

您可以从您的活动中调用此方法

  geoService.startService(dangerous_area,2000);

即使您的应用程序被销毁，这也将起作用。

完整代码如下

public class MapsActivity extends FragmentActivity implements OnMapReadyCallback {


    private GoogleMap mMap;
    //Play Service Location
    private static final int MY_PERMISSION_REQUEST_CODE = 7192;
    private static final int PLAY_SERVICE_RESULATION_REQUEST = 300193;

    private Location mLastLocaiton;

    private static int UPDATE_INTERVAL = 5000;
    private static int FATEST_INTERVAL = 3000;
    private static int DISPLACEMENT = 10;


    Marker mCurrent;
    VerticalSeekBar mVerticalSeekBar;
    private static final String TAG = MapsActivity.class.getSimpleName();

    private GeoService geoService;
    private boolean serviceBound;

    @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.



        mVerticalSeekBar = (VerticalSeekBar) findViewById(R.id.verticalSeekBar);
        mVerticalSeekBar.setOnSeekBarChangeListener(new SeekBar.OnSeekBarChangeListener() {
            @Override
            public void onProgressChanged(SeekBar seekBar, int progress, boolean fromUser) {
                mMap.animateCamera(CameraUpdateFactory.zoomTo(progress), 1500, null);
            }

            @Override
            public void onStartTrackingTouch(SeekBar seekBar) {

            }

            @Override
            public void onStopTrackingTouch(SeekBar seekBar) {

            }
        });



    }

    @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 (checkPlayService()) {
                        geoService.buildGoogleApiClient();
                        geoService.createLocationRequest();
                        geoService.displayLocation();
                        geoService.setLocationChangeListener(new GeoService.LocationChangeListener() {
                            @Override
                            public void onLocationChange(Location location) {
                                if (mCurrent != null)
                                    mCurrent.remove();
                                mCurrent = mMap.addMarker(new MarkerOptions()
                                        .position(new LatLng(location.getLatitude(), location.getLongitude()))
                                        .title("You"));
                                LatLng coordinate = new LatLng(location.getLatitude(), location.getLongitude());
                                CameraUpdate yourLocation = CameraUpdateFactory.newLatLngZoom(coordinate, 12);
                                mMap.animateCamera(yourLocation);
                            }
                        });
                    }
                }
                break;
        }
    }

    private void setUpdateLocation() {
        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
                ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
            ActivityCompat.requestPermissions(this, new String[]{
                    Manifest.permission.ACCESS_COARSE_LOCATION,
                    Manifest.permission.ACCESS_FINE_LOCATION
            }, MY_PERMISSION_REQUEST_CODE);
        } else {
            if (checkPlayService()) {
                geoService.buildGoogleApiClient();
                geoService.createLocationRequest();
                geoService.displayLocation();
                geoService.setLocationChangeListener(new GeoService.LocationChangeListener() {
                    @Override
                    public void onLocationChange(Location location) {
                        if (mCurrent != null)
                            mCurrent.remove();
                        mCurrent = mMap.addMarker(new MarkerOptions()
                                .position(new LatLng(location.getLatitude(), location.getLongitude()))
                                .title("You"));
                        LatLng coordinate = new LatLng(location.getLatitude(), location.getLongitude());
                        CameraUpdate yourLocation = CameraUpdateFactory.newLatLngZoom(coordinate, 12);
                        mMap.animateCamera(yourLocation);
                    }
                });
            }
        }
    }


    private boolean checkPlayService() {
        GoogleApiAvailability googleAPI = GoogleApiAvailability.getInstance();
        int result = googleAPI.isGooglePlayServicesAvailable(this);
        if (result != ConnectionResult.SUCCESS) {
            if (googleAPI.isUserResolvableError(result)) {
                googleAPI.getErrorDialog(this, result, PLAY_SERVICE_RESULATION_REQUEST).show();
            } else {
                Toast.makeText(this, "This Device is not supported.", Toast.LENGTH_SHORT).show();
            }
            return false;
        }

        return true;
    }

    @Override
    public void onMapReady(GoogleMap googleMap) {
        mMap = googleMap;

        LatLng dangerous_area = new LatLng(8.5324236, 76.8842189);
        mMap.addCircle(new CircleOptions()
                .center(dangerous_area)
                .radius(2000)
                .strokeColor(Color.BLUE)
                .fillColor(0x220000FF)
                .strokeWidth(5.0f));

        geoService.startService(dangerous_area,2000);


    }


    @Override
    protected void onStart() {
        super.onStart();
        if (Log.isLoggable(TAG, Log.VERBOSE)) {
            Log.v(TAG, "Starting and binding service");
        }
        Intent i = new Intent(this, GeoService.class);
        startService(i);
        bindService(i, mConnection, 0);

    }

    @Override
    protected void onStop() {
        super.onStop();
        if (serviceBound) {
            // If a timer is active, foreground the service, otherwise kill the service
            if (geoService.isServiceRunning()) {
                geoService.foreground();
            } else {
                stopService(new Intent(this, GeoService.class));
            }
            // Unbind the service
            unbindService(mConnection);
            serviceBound = false;
        }
    }

    /**
     * Callback for service binding, passed to bindService()
     */
    private ServiceConnection mConnection = new ServiceConnection() {

        @Override
        public void onServiceConnected(ComponentName className, IBinder service) {
            if (Log.isLoggable(TAG, Log.VERBOSE)) {
                Log.v(TAG, "Service bound");
            }
            GeoService.RunServiceBinder binder = (GeoService.RunServiceBinder) service;
            geoService = binder.getService();
            serviceBound = true;
            // Ensure the service is not in the foreground when bound
            geoService.background();
            setUpdateLocation();
            SupportMapFragment mapFragment = (SupportMapFragment) getSupportFragmentManager()
                    .findFragmentById(R.id.map);
            mapFragment.getMapAsync(MapsActivity.this);

        }

        @Override
        public void onServiceDisconnected(ComponentName name) {
            if (Log.isLoggable(TAG, Log.VERBOSE)) {
                Log.v(TAG, "Service disconnect");
            }
            serviceBound = false;
        }
    };


    public static class GeoService extends Service implements GoogleApiClient.ConnectionCallbacks,
            GoogleApiClient.OnConnectionFailedListener,
            LocationListener {
        private LocationRequest mLocationRequest;
        private GoogleApiClient mGoogleApiClient;
        private Location mLastLocation;
        private DatabaseReference ref;
        private GeoFire geoFire;
        private LocationChangeListener mLocationChangeListener;
        private static final String TAG = GeoService.class.getSimpleName();


        // Is the service tracking time?
        private boolean isServiceRunning;

        // Foreground notification id
        private static final int NOTIFICATION_ID = 1;

        // Service binder
        private final IBinder serviceBinder = new RunServiceBinder();
        private GeoQuery geoQuery;

        public class RunServiceBinder extends Binder {
            GeoService getService() {
                return GeoService.this;
            }
        }

        @Override
        public void onCreate() {
            if (Log.isLoggable(TAG, Log.VERBOSE)) {
                Log.v(TAG, "Creating service");
            }
            ref = FirebaseDatabase.getInstance().getReference("MyLocation");
            geoFire = new GeoFire(ref);
            isServiceRunning = false;
        }

        @Override
        public int onStartCommand(Intent intent, int flags, int startId) {
            if (Log.isLoggable(TAG, Log.VERBOSE)) {
                Log.v(TAG, "Starting service");
            }
            return Service.START_STICKY;
        }

        @Override
        public IBinder onBind(Intent intent) {
            if (Log.isLoggable(TAG, Log.VERBOSE)) {
                Log.v(TAG, "Binding service");
            }
            return serviceBinder;
        }

        @Override
        public void onDestroy() {
            super.onDestroy();
            if (Log.isLoggable(TAG, Log.VERBOSE)) {
                Log.v(TAG, "Destroying service");
            }
        }

        /**
         * Starts the timer
         */
        public void startService(LatLng latLng, double radius) {
            if (!isServiceRunning) {
                isServiceRunning = true;

            } else {
                Log.e(TAG, "startService request for an already running Service");

            }
            if (geoQuery!=null){
                geoQuery.removeAllListeners();
            }
            geoQuery = geoFire.queryAtLocation(new GeoLocation(latLng.latitude, latLng.longitude), 2f);
            geoQuery.addGeoQueryEventListener(new GeoQueryEventListener() {
                @Override
                public void onKeyEntered(String key, GeoLocation location) {
                    sendNotification("MRF", String.format("%s entered the dangerous area", key));
                }

                @Override
                public void onKeyExited(String key) {
                    sendNotification("MRF", String.format("%s exit the dangerous area", key));
                }

                @Override
                public void onKeyMoved(String key, GeoLocation location) {
                    Log.d("MOVE", String.format("%s move within the dangerous area [%f/%f]", key, location.latitude, location.longitude));
                }

                @Override
                public void onGeoQueryReady() {

                }

                @Override
                public void onGeoQueryError(DatabaseError error) {
                    Log.d("ERROR", "" + error);
                }
            });
        }

        /**
         * Stops the timer
         */
        public void stopService() {
            if (isServiceRunning) {
                isServiceRunning = false;
                geoQuery.removeAllListeners();
            } else {
                Log.e(TAG, "stopTimer request for a timer that isn't running");
            }
        }

        /**
         * @return whether the service is running
         */
        public boolean isServiceRunning() {
            return isServiceRunning;
        }


        /**
         * Place the service into the foreground
         */
        public void foreground() {
            startForeground(NOTIFICATION_ID, createNotification());
        }

        /**
         * Return the service to the background
         */
        public void background() {
            stopForeground(true);
        }

        /**
         * Creates a notification for placing the service into the foreground
         *
         * @return a notification for interacting with the service when in the foreground
         */
        private Notification createNotification() {
            NotificationCompat.Builder builder = new NotificationCompat.Builder(this)
                    .setContentTitle("Service is Active")
                    .setContentText("Tap to return to the Map")
                    .setSmallIcon(R.mipmap.ic_launcher);

            Intent resultIntent = new Intent(this, MapsActivity.class);
            PendingIntent resultPendingIntent =
                    PendingIntent.getActivity(this, 0, resultIntent,
                            PendingIntent.FLAG_UPDATE_CURRENT);
            builder.setContentIntent(resultPendingIntent);

            return builder.build();
        }

        private void sendNotification(String title, String content) {
            Notification.Builder builder = new Notification.Builder(this)
                    .setSmallIcon(R.mipmap.ic_launcher)
                    .setContentTitle(title)
                    .setContentText(content);

            NotificationManager manager = (NotificationManager) this.getSystemService(Context.NOTIFICATION_SERVICE);
            Intent intent = new Intent(this, MapsActivity.class);
            PendingIntent contentIntent = PendingIntent.getActivity(this, 0, intent, PendingIntent.FLAG_IMMUTABLE);
            builder.setContentIntent(contentIntent);
            Notification notification = builder.build();
            notification.flags |= Notification.FLAG_AUTO_CANCEL;
            notification.defaults |= Notification.DEFAULT_SOUND;
            manager.notify(new Random().nextInt(), notification);
        }

        @Override
        public void onConnected(@Nullable Bundle bundle) {
            displayLocation();
            startLocationUpdate();
        }

        private void startLocationUpdate() {
            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 onConnectionSuspended(int i) {
            mGoogleApiClient.connect();
        }

        @Override
        public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {

        }

        @Override
        public void onLocationChanged(Location location) {
            mLastLocation = location;
            displayLocation();
        }

        interface LocationChangeListener {
            void onLocationChange(Location location);
        }

        private void createLocationRequest() {
            mLocationRequest = new LocationRequest();
            mLocationRequest.setInterval(UPDATE_INTERVAL);
            mLocationRequest.setFastestInterval(FATEST_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 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) {
                final double latitude = mLastLocation.getLatitude();
                final double longitude = mLastLocation.getLongitude();

                geoFire.setLocation("You", new GeoLocation(latitude, longitude), new GeoFire.CompletionListener() {
                    @Override
                    public void onComplete(String key, DatabaseError error) {
                        if (mLocationChangeListener!=null) {
                            mLocationChangeListener.onLocationChange(mLastLocation);
                        }
                    }
                });

                Log.d("MRF", String.format("Your last location was chaged: %f / %f", latitude, longitude));
            } else {
                Log.d("MRF", "Can not get your location.");
            }
        }

        public void setLocationChangeListener(LocationChangeListener mLocationChangeListener) {
            this.mLocationChangeListener = mLocationChangeListener;
        }
    }

}

不要忘记将服务添加到清单中

  <service android:name=".MapsActivity$GeoService" />

完整源码github.com/vinayakb73/GeoFence-GeoFire