WearOS中的SensorManager问题

Question

我正在尝试获取加速度计的数据，但我无法在需要的时候获取它。我想要每秒20堂课，这并不重要。问题是我收到了更多的东西，比如最大可能的。我一直在看文档，但我每秒仍然能实现100次。代码如下：

public class MainActivity extends WearableActivity implements SensorEventListener {



private SensorManager mSensorManager;
private Sensor mAcceSensor;
private final static String TAG = "Wear MainActivity";
private TextView mTextView;
private Button myButton;
private ToggleButton activateSensors;
private int num = 1;
public boolean isOn;
private String datapath = "/message_path";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main_activity);
    mTextView =  findViewById(R.id.text);

    //send a message from the wear.  This one will not have response.
    myButton =  findViewById(R.id.wrbutton);
    activateSensors = findViewById(R.id.toggleButton);
    activateSensors.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
        @Override
        public void onCheckedChanged(CompoundButton compoundButton, boolean isChecked) {
            if(isChecked) isOn = true;
            else isOn = false;
        }
    });

    myButton.setOnClickListener(new View.OnClickListener() {
        @Override
        public void onClick(View v) {
            String message = "Hello device " + num;
            //Requires a new thread to avoid blocking the UI
            new SendThread(datapath, message).start();
            num++;
        }
    });

    // Register the local broadcast receiver to receive messages from the listener.
    IntentFilter messageFilter = new IntentFilter(Intent.ACTION_SEND);
    MessageReceiver messageReceiver = new MessageReceiver();
    LocalBroadcastManager.getInstance(this).registerReceiver(messageReceiver, messageFilter);

    mSensorManager = (SensorManager)getSystemService(Context.SENSOR_SERVICE);
    mAcceSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);

    // Enables Always-on
    setAmbientEnabled();
}

@Override
protected void onResume() {
    super.onResume();
    mSensorManager.registerListener(this, mAcceSensor,
            50000, 50000);
}

@Override
protected void onPause() {
    super.onPause();
    mSensorManager.unregisterListener(this, mAcceSensor);
}

@Override
public void onSensorChanged(SensorEvent sensorEvent) {
    if(sensorEvent.sensor.getType() == Sensor.TYPE_ACCELEROMETER){
        String msg = Float.toString(sensorEvent.values[0]) +","+ Float.toString(sensorEvent.values[1]) +","+ Float.toString(sensorEvent.values[2])+","+getCurrentTimeStamp();
        if (isOn){
                new SendThread(datapath, msg).start();
        }
    }
}

public static String getCurrentTimeStamp(){
    try {

        SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");
        String currentDateTime = dateFormat.format(new Date()); // Find todays date
        return currentDateTime;
    } catch (Exception e) {
        e.printStackTrace();

        return null;
    }
}

@Override
public void onAccuracyChanged(Sensor sensor, int i) {

}

(Now a block about sending from one device to the other)
}

如您所见，我将侦听器定义为: mSensorManager.registerListener(this，mAcceSensor，50000,50000)；

这应该会让我每50毫秒实现一次，但我得到的要多得多。

Answer 1

我一直在四处寻找，我发现自2016年以来，在WearOS中，你在这里尝试的代码并不重要：

mSensorManager.registerListener(this，mAcceSensor，50000,50000)；

如果你使用了

 mSensorManager.registerListener(this, mAcceSensor, SensorManager.SENSOR_DELAY_UI);

或者mSensorManager.registerListener(this，mAcceSensor，SensorManager.SENSOR_DELAY_FASTEST)；

或者我的代码，它总是使用最快的采样率，大约100 Hz。

Galaxy Nexus: Sensor Sampling Rate becomes faster when sampling more Sensors

Android sensor sampling rate won't drow below 60 hz

最后，我选择了一种低级的方式：

@Override
public void onSensorChanged(SensorEvent sensorEvent) {
    nowDate = new Date();
    if(sensorEvent.sensor.getType() == Sensor.TYPE_ACCELEROMETER){
        String msg = Float.toString(sensorEvent.values[0]) +","+ Float.toString(sensorEvent.values[1]) +","+ Float.toString(sensorEvent.values[2]);
        if (isOn && (nowDate.getTime() -startDate.getTime()) >= 40){
                startDate = nowDate;
                String timeStamp = dateFormat.format(nowDate);
                msg = msg +","+timeStamp;
                new SendThread(datapath, msg).start();
        }
    }
}

它工作，它不是完美的，但它工作得足够好。似乎我在if条件中选择的值并不重要，我已经尝试了40，50和60，几乎都得到了完美的16-17 the。我也尝试过从SENSOR_DELAY_UI到SENSOR_DELAY_FASTEST，我得到了相同的结果，16-17 to始终如一，所以这不是选择的问题。

我希望这对有同样问题的人有所帮助，如果有更时尚的方式，我会阅读。