Question

我把加速度计代码投入使用。但是当屏幕关闭时它会停止。通过usb插入电话时它不会停止，但是在未插入电话时它会停止。所有帖子都说服务中的加速度计不会停止。但是我的代码中的加速度计即使在服务中也会停止。这是我的代码。我需要在代码中添加什么？（我的测试手机是三星Galaxy S3 3G。）

// Service
public class LocalService extends Service {
    private final IBinder mBinder = new LocalBinder();
    private final Random mGenerator = new Random();

    private SensorManager senSensorManager;
    private Sensor senAccelerometer;

    @Override
    public void onCreate() {
        super.onCreate();
        Log.i("t", "onCreate");

        senSensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
        senAccelerometer = senSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);
        senSensorManager.registerListener(mSensorEventListener, senAccelerometer, SensorManager.SENSOR_DELAY_NORMAL);
    }
    @Override
    public void onDestroy() {
        super.onDestroy();
        senSensorManager.unregisterListener(mSensorEventListener);
        // this sound is for checking
        try {
            Uri notification = RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION);
            Ringtone r = RingtoneManager.getRingtone(getApplicationContext(), notification);
            r.play();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
    private SensorEventListener mSensorEventListener = new SensorEventListener() {
        @Override
        public void onSensorChanged(SensorEvent event) {
            Sensor mySensor = event.sensor;

            if (mySensor.getType() == Sensor.TYPE_ACCELEROMETER) {
                // this vibrator is for checking
                Vibrator vibe = (Vibrator) getSystemService(Context.VIBRATOR_SERVICE);
                vibe.vibrate(100);
                //Log.i("t", "onSensorChanged");
            }
        }
        @Override
        public void onAccuracyChanged(Sensor sensor, int accuracy) {}
    };
    public class LocalBinder extends Binder {
        LocalService getService() {
            return LocalService.this;
        }
    }
    @Override
    public IBinder onBind(Intent intent) {
        return mBinder;
    }
    public int getRandomNumber() {
        return mGenerator.nextInt(100);
    }
}
// Activity
public class MainActivity extends ActionBarActivity {
    LocalService mService;
    boolean mBound = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        Button button = (Button) this.findViewById(R.id.button);
        button.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View v) {
                if (mBound) {
                    int num = mService.getRandomNumber();
                    Toast.makeText(getBaseContext(), "number: " + num, Toast.LENGTH_SHORT).show();
                }
            }
        });
        Intent intent = new Intent(this, LocalService.class);
        bindService(intent, mConnection, Context.BIND_AUTO_CREATE);
    }
    @Override
    protected void onDestroy() {
        super.onDestroy();

        if (mBound) {
            unbindService(mConnection);
            mBound = false;
        }
    }
    private ServiceConnection mConnection = new ServiceConnection() {

        @Override
        public void onServiceConnected(ComponentName className,
                                       IBinder service) {
            // We've bound to LocalService, cast the IBinder and get LocalService instance
            LocalService.LocalBinder binder = (LocalService.LocalBinder) service;
            mService = binder.getService();
            mBound = true;
        }

        @Override
        public void onServiceDisconnected(ComponentName arg0) {
            mBound = false;
        }
    };

//添加了我决定使用PARTIAL_WAKE_LOCK。这对我来说是最好的解决方案。读这个。 http://nosemaj.org/android-persistent-sensors http://nosemaj.org/android-persistent-sensors

Answer 1

在您的代码中，您使用LocalService 绑定加入Activity（您正在调用bindService和{{ 1}}）。这样做会导致您服务停止然后停止活动，因为您的服务充当bound service并在最后一次绑定关闭时停止。 See bound service lifecycle for reference

如果你真的希望你的服务一直运行不要绑定它 - 你应该只是在某个地方开始（使用startService方法），然后停止那时你真的不再需要加速度计跟踪。

修改

如果问题不是服务停止，而是加速计停止，那么您应该maintain the wakelock，否则设备将关闭，传感器将不会向您报告任何数据。

服务中的android加速度计在屏幕关闭时停止

1 个答案: