Question

当我们从最近的应用中清除应用时，服务会停止工作吗？因为当我在代码下运行时。要在位置发生变化时更新lat，lng。当我从最近的应用程序中清除应用程序时，位置更新将停止。当我看到正在运行的应用程序视图时，服务处于运行状态。请清楚地了解服务将如何正常工作。谢谢进展。

  public class GPSTracker extends Service implements
    ConnectionCallbacks,
    OnConnectionFailedListener,
    LocationListener, GooglePlayServicesClient.ConnectionCallbacks {

public static final long UPDATE_INTERVAL = 5000;
public static final long FASTEST_INTERVAL = 1000;

private LocationClient mLocationClient;
private LocationRequest mLocationRequest;
private boolean mInProgress;
private boolean servicesAvailable = false;
DatabaseHandler db;
@Override
public void onCreate() {
    super.onCreate();

    mInProgress = false;
    mLocationRequest = LocationRequest.create()
            .setPriority(LocationRequest.PRIORITY_BALANCED_POWER_ACCURACY)

       .setInterval(UPDATE_INTERVAL) // Set the update interval to 5 seconds
      .setFastestInterval(FASTEST_INTERVAL); // Set the fastest update interval to 1 second

    servicesAvailable = servicesConnected();
    setUpLocationClientIfNeeded();
     db = new DatabaseHandler(this);
}

private boolean servicesConnected() {
    int resultCode = GooglePlayServicesUtil.isGooglePlayServicesAvailable(this);
    return ConnectionResult.SUCCESS == resultCode;
}

@Override
public int onStartCommand(Intent intent, int flags, int startId) {
    super.onStartCommand(intent, flags, startId);
    Log.d("TAG", "onLocationChanged onStart Command");
    if (!servicesAvailable || mLocationClient.isConnected() || mInProgress)
        return START_STICKY;

    setUpLocationClientIfNeeded();

    if (!mLocationClient.isConnected() || !mLocationClient.isConnecting() && !mInProgress) {
        mInProgress = true;
        mLocationClient.connect();
    }

    return START_STICKY;
}

@Override
public IBinder onBind(Intent intent) {
    return null;
}

  @Override
   public void onDestroy() {
 /*   mInProgress = false;
    if (servicesAvailable && mLocationClient != null) {
        mLocationClient.removeLocationUpdates( this);
        mLocationClient = null;
    }
   */
    super.onDestroy();
}

private void setUpLocationClientIfNeeded() {
    if (mLocationClient == null)
        mLocationClient = new LocationClient(this, this, this);
}

/*
 * LocationListener Callbacks
 */

@Override
public void onLocationChanged(Location location) {
    //Carnival.updateLocation(location);
    Log.d("TAG", "onLocationChanged " + location.getLongitude());
    Log.d("Insert: ", "Inserting ..");
    db.addContact(new Contact("" + location.getTime(), " Latitude " + location.getLatitude() + " Longitude " + location.getLongitude()));

}



/*
* GooglePlayServicesClient Callbacks
*/

@Override
public void onConnected(Bundle bundle) {
    if (mLocationClient != null) {
        mLocationClient.requestLocationUpdates(mLocationRequest, this);
    }
}

@Override
public void onDisconnected() {

}

@Override
public void onConnectionSuspended(int i) {

}



@Override
public void onConnectionFailed(ConnectionResult connectionResult) {
    mInProgress = false;
    /*
    * Google Play services can resolve some errors it detects.
    * If the error has a resolution, try sending an Intent to
    * start a Google Play services activity that can resolve
    * error.
    */
    if (!connectionResult.hasResolution()) {
        // If no resolution is available, display an error dialog
    }
}
}

Answer 1

常规Service不足以确保系统在他/她从最近列表中清除我们的应用时不会杀死它。

出于特定目的，告诉系统您希望Service作为foreground运行：

前台服务是一种被认为是某种东西的服务用户积极地意识到并因此不是系统的候选者要杀...

您可以在Service：

中调用此方法

    Notification notification = new Notification(R.drawable.icon, getText(R.string.ticker_text), System.currentTimeMillis());
    Intent notificationIntent = new Intent(this, ExampleActivity.class);
    PendingIntent pendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0);

    notification.setLatestEventInfo(this, getText(R.string.notification_title),
        getText(R.string.notification_message), pendingIntent);

    startForeground(ONGOING_NOTIFICATION_ID, notification);

如您所见，startForeground()将Notification作为其参数之一。最终，它会设置persistent notification来通知用户您的Service当前正在后台运行。

在对此进行了更多研究之后，似乎使Service前景不足以确保其在这样的条件下持续存在。

当我们的应用程序从“最近”列表中删除时，会有一个解决方法是监听，并通过这样做明确地从那里重新启动Service：

    @Override 
    public void onTaskRemoved(Intent rootIntent){
         Intent restartServiceIntent = new Intent(getApplicationContext(), this.getClass());

         PendingIntent restartServicePendingIntent = PendingIntent.getService(
         getApplicationContext(), 1, restartServiceIntent, PendingIntent.FLAG_ONE_SHOT);
         AlarmManager alarmService = (AlarmManager) getSystemService(Context.ALARM_SERVICE);
         alarmService.set(ELAPSED_REALTIME, elapsedRealtime() + 1000, restartServicePendingIntent);

         super.onTaskRemoved(rootIntent); 
    }

当然，您必须在清单上的Service声明中添加适当的标记（请参阅Max Rockwood's answer）。

Answer 2

您需要在清单中设置stopWithTask=false以进行服务。

这样的事情：

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

它会阻止服务停止，如果我们要执行任何可以对其进行操作的操作，如果我们从最近清除应用程序，则会调用方法onTaskRemoved()。

Answer 3

有一个名为OnStartCommand（）的事件覆盖它并在该函数中再次调用该活动

当我们从最近的应用中清除应用时，服务将停止工作？

3 个答案: