IntentService STICKY和传感器监控在Android中不应该停止

时间:2012-02-29 14:45:50

标签: android android-intent android-sensors intentservice

在我的应用程序onCreate中,我检查一些条件,然后我开始这样的活动:

Intent startIntent = new Intent(getApplicationContext(), EnableLocationProviderActivity.class);
startIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
getApplicationContext().startActivity(startIntent);

从该Activity开始,我启动一个IntentService,为传感器注册一些监听器,它以STICKY开头,意味着它应该被显式停止。 IntentService监视传感器。

我的问题是,当我回到第一个Activity时,传感器不再感应了(我将一个Log.v放在onSensorChanged中(开始显示数据,然后停止)。

如果我没有明确停止它,为什么它会停止? 此外,我看到有时会调用IntentService的OnDestroy,但是,如果它是STICKY并且我没有调用stopself()并且没有以任何其他方式停止,那么如何调用它呢?

谢谢!吉列尔莫。

修改

这是IntentService的代码(它应该一直运行,尽管手机进入睡眠状态或按下主页按钮(我知道电池和其他一切,用户将被警告此事,并且有机会在他想要的时候关闭申请。

从MainActivity调用服务,如下所示:

Intent startIntent = new Intent(GdpTesisApplication.getInstance().getApplicationContext(), SensingService.class);
startService(startIntent);

服务代码就是这个:

public class SensingService extends IntentService implements SensorEventListener {
    private float[] mAccelerationValues;
    private SensorManager mSensorManager = null;
    String sensorType = "";

    public SensingService(String name) {
        super(name);
        setIntentRedelivery(true);
    }

    public SensingService() {
        super("SensingService");
        setIntentRedelivery(true);
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId) {
        Log.v(ApplicationName,"SensingService.onStartCommand");
        super.onStartCommand(intent, flags, startId); // If this is not written then onHandleIntent is not called.
        return START_STICKY;
    }

    @Override
    public void onCreate() {
        super.onCreate();
        Log.v(ApplicationName, "SensingService.onCreate");
        initialize();
    }

    private void initialize() {
        mSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE); // This must be in onCreate since it needs the Context to be created.
        mAccelerationValues = new float[3];

        Log.v(ApplicationName, "Opening Location Service from Sensing Service");
        LocationService myLocation = new LocationService();
        myLocation.getLocation(this, locationResult);
    }

    @Override
    public void onDestroy() {
        Log.v(ApplicationName, "SensingService.onDestroy");
        super.onDestroy();
        if (mSensorManager != null) {
            mSensorManager.unregisterListener(this);
        }
    }

    @Override
    protected void onHandleIntent(Intent intent) {
        Log.v(ApplicationName, "SensingService.onHandleIntent");
        if (mSensorManager != null) {
            registerListeners();
        }
    }

    public LocationResult locationResult = new LocationResult() {
        @Override
        public void gotLocation(final Location location) {
            if (location != null) {
                Log.v(ApplicationName, "Location != null : (" + location.getLatitude() + "," + location.getLongitude() + ")");
            } else {
                Log.v(ApplicationName, "Location == null : (0,0)");
            }
        }
    };

    public void onAccuracyChanged(Sensor sensor, int accuracy) {
    }

    public void onSensorChanged(SensorEvent currentEvent) {
        if (currentEvent.accuracy == SensorManager.SENSOR_STATUS_UNRELIABLE) {
            return;
        }

        synchronized (this) {
            float[] accelVals = null;
            float totalForce = 0.0f;

            int sensor = currentEvent.sensor.getType();
            System.arraycopy(currentEvent.values, 0, mAccelerationValues, 0, 3); // We use System.arraycopy because of this:
            switch (sensor) {
            case Sensor.TYPE_ACCELEROMETER:
                sensorType = "Accelerometer";
                totalForce = SensorsHelpers.getTotalForceInGs(mAccelerationValues); 
                break;
            case Sensor.TYPE_LINEAR_ACCELERATION:
                sensorType = "LinearAcceleration";
                totalForce = SensorsHelpers.getTotalForceInGs(mAccelerationValues) + 1; 
                break;
            case Sensor.TYPE_GRAVITY:
                totalForce = SensorsHelpers.getTotalForceInGs(mAccelerationValues); 
                sensorType = "Gravity";
                break;
            } 
            Log.v(ApplicationName,DateHelper.GetUTCdatetimeFromDate(new Date()) + " - from sensingService");
        }
    }

    private void registerListeners() {
        Log.v(ApplicationName, "Registering sensors listeners");
        mSensorManager.registerListener(this, mSensorManager.getDefaultSensor(Sensor.TYPE_LINEAR_ACCELERATION), SensorManager.SENSOR_DELAY_UI);
        mSensorManager.registerListener(this, mSensorManager.getDefaultSensor(Sensor.TYPE_GRAVITY),SensorManager.SENSOR_DELAY_UI);
        mSensorManager.registerListener(this, mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER), SensorManager.SENSOR_DELAY_UI);
    }
}

更新2

现在我在方法onCreate上添加了这个:

int NOTIFICATION_ID = 1;
Intent intent = new Intent(this, MainActivity.class);
PendingIntent pi = PendingIntent.getActivity(this, 1, intent, 0);
Notification notification = new Notification(R.drawable.ic_dialog_info, "Running in the Foregound", System.currentTimeMillis());
notification.setLatestEventInfo(this, "Title", "Text", pi);
notification.flags = notification.flags | Notification.FLAG_ONGOING_EVENT;
startForeground(NOTIFICATION_ID, notification);

将其作为startForground启动,但它将图标放在通知栏中,然后在服务中调用onDestroy,通知图标就会消失。

我现在绝望了!请帮帮忙!

谢谢!吉列尔莫。

2 个答案:

答案 0 :(得分:8)

根据IntentService documentation

  

根据需要启动服务,使用a依次处理每个Intent   工作线程,并在工作失效时自行停止

另外,根据相同的文档,您不应该覆盖onStartCommand()中的onDestroy()IntentService,我假设是因为它实现了自己的特殊行为,如上所述。也许您需要延长Service而不是IntentService

答案 1 :(得分:-2)

好的,我看到了另一个问题的回复,并且有一个人说这是Android中的一个错误,我按照他的建议将代码移到onCreate而不是onHandleIntent并且它有效!所以,如果没有人向我展示这是我的代码的问题,对我来说这将是一个错误。谢谢!