某些时代定位服务无法在后台工作

Question

我在android应用程序中使用了定位服务，该应用程序扩展了服务并实现了GoogleApiClient LocationListener。我正在LocationChanged((方法上更新位置，我的操作更新间隔是20秒。有时，即使应用程序在后台，定位服务也无法工作。无论如何，我想一直运行我的定位服务。每一个版本的安卓&每一部手机，即使该应用程序也在后台杀人。我也使用AlarmManager调用定位服务。我在onStartCommand((方法中调用了位置更新。如果定位服务被停止，那么它将再次转到该方法中的onDestroy((方法或onTaskRemoved((方法。我正在调用startLocation方法，比如

startService(new Intent(this, LocationService.class));

我的服务清单代码：

<service
android:name=".LocationService"
android:enabled="true"
android:stopWithTask="false"
/>

Answer 1

您可以创建如下定位服务。该服务在后台和前台模式上运行

public class ServiceLocation extends Service implements
GoogleApiClient.ConnectionCallbacks,
GoogleApiClient.OnConnectionFailedListener,
LocationListener {
private static final String NOTIFICATION_CHANNEL_ID = "my_notification_location";
private static final long TIME_INTERVAL_GET_LOCATION = 1000 * 5; // 1 Minute
private static final long MIN_DISTANCE_CHANGE_FOR_UPDATES = 7; // meters
private Handler handlerSendLocation;
private Context mContext;
private GoogleApiClient mGoogleApiClient;
private LocationRequest mLocationRequest;
private final static int CONNECTION_FAILURE_RESOLUTION_REQUEST = 5000;
Location locationData;
@Override
public void onCreate() {
super.onCreate();
mGoogleApiClient = new GoogleApiClient.Builder(this)
.addConnectionCallbacks(this)
.addOnConnectionFailedListener(this)
.addApi(LocationServices.API)
.build();
// Create the LocationRequest object
mLocationRequest = LocationRequest.create()
.setPriority(LocationRequest.PRIORITY_HIGH_ACCURACY)
.setInterval(TIME_INTERVAL_GET_LOCATION)    // 3 seconds, in milliseconds
.setFastestInterval(TIME_INTERVAL_GET_LOCATION); // 1 second, in milliseconds
mContext = this;

NotificationCompat.Builder builder = new NotificationCompat.Builder(this, NOTIFICATION_CHANNEL_ID)
.setOngoing(false)
.setSmallIcon(R.drawable.ic_notification)
.setColor(getResources().getColor(R.color.fontColorDarkGray))
.setPriority(Notification.PRIORITY_MIN);
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
NotificationManager notificationManager = (NotificationManager) getSystemService(Context.NOTIFICATION_SERVICE);
NotificationChannel notificationChannel = new NotificationChannel(NOTIFICATION_CHANNEL_ID,
NOTIFICATION_CHANNEL_ID, NotificationManager.IMPORTANCE_LOW);
notificationChannel.setDescription(NOTIFICATION_CHANNEL_ID);
notificationChannel.setSound(null, null);
notificationManager.createNotificationChannel(notificationChannel);
startForeground(1, builder.build());
}
}
@Override
public IBinder onBind(Intent arg0) {
return null;
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
Log.w("Service Update Location", "BGS > Started");
if (handlerSendLocation == null) {
handlerSendLocation = new Handler();
handlerSendLocation.post(runnableSendLocation);
Log.w("Service Send Location", "BGS > handlerSendLocation Initialized");
} else {
Log.w("Service Send Location", "BGS > handlerSendLocation Already Initialized");
}
return START_STICKY;
}
private Runnable runnableSendLocation = new Runnable() {
@Override
public void run() {

// You can get Location
//locationData and Send Location X Minutes
if (locationData != null) {
Intent intent = new Intent("GPSLocationUpdates");
intent.putExtra("Latitude", "" + locationData.getLatitude());
intent.putExtra("Longitude", "" + locationData.getLongitude());

LocalBroadcastManager.getInstance(mContext).sendBroadcast(intent);
Log.w("==>UpdateLocation<==", "" + String.format("%.6f", locationData.getLatitude()) + "," +
String.format("%.6f", locationData.getLongitude()));
Log.w("Service Send Location", "BGS >> Location Updated");
}
if (handlerSendLocation != null && runnableSendLocation != null)
handlerSendLocation.postDelayed(runnableSendLocation, TIME_INTERVAL_GET_LOCATION);
}
};

@Override
public void onConnected(@Nullable Bundle bundle) {
if (ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_FINE_LOCATION) != PackageManager.PERMISSION_GRANTED &&
ActivityCompat.checkSelfPermission(mContext, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {
return;
}

FusedLocationProviderClient mFusedLocationClient = LocationServices.getFusedLocationProviderClient(this);
mFusedLocationClient.requestLocationUpdates(mLocationRequest, new LocationCallback() {
@Override
public void onLocationResult(LocationResult locationResult) {
locationData = locationResult.getLastLocation();
}
}, null);
}
@Override
public void onConnectionSuspended(int i) {
}
@Override
public void onConnectionFailed(@NonNull ConnectionResult connectionResult) {
if (connectionResult.hasResolution() && mContext instanceof Activity) {
try {
Activity activity = (Activity) mContext;
connectionResult.startResolutionForResult(activity, CONNECTION_FAILURE_RESOLUTION_REQUEST);
} catch (Exception e) {
e.printStackTrace();
}
} else {
Log.i("", "Location services connection failed with code " + connectionResult.getErrorCode());
}
}
@Override
public void onLocationChanged(Location location) {
Log.w("==>UpdateLocation<==", "" + String.format("%.6f", location.getLatitude()) + "," + String.format("%.6f", location.getLongitude()));
locationData = location;
}
@Override
public void onDestroy() {
if (handlerSendLocation != null)
handlerSendLocation.removeCallbacks(runnableSendLocation);

Log.w("Service Update Info", "BGS > Stopped");
stopSelf();
super.onDestroy();
}

}

在android清单文件中声明此服务，如下

<service
android:name=".ServiceLocation"
android:enabled="true"
android:exported="true" />

您可以使用此代码从活动开始服务

if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
ContextCompat.startForegroundService(MainActivity.this, new Intent(MainActivity.this, ServiceLocation.class));
} else {
startService(new Intent(MainActivity.this, ServiceLocation.class));
}