Android传感器手波检测

Question

I'm trying to implement a sensor that can detect a hand wave. I found an example that can do hand hover, but not hand wave.

The following code I used is from How to controlandroid proximity sensor?

public class AndroidProximitySensorActivity extends Activity {

 TextView ProximitySensor, ProximityMax, ProximityReading;

 SensorManager mySensorManager;
 Sensor myProximitySensor;

@Override
public void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.main);
    ProximitySensor = (TextView)findViewById(R.id.proximitySensor);
    ProximityMax = (TextView)findViewById(R.id.proximityMax);
    ProximityReading = (TextView)findViewById(R.id.proximityReading);

    mySensorManager = (SensorManager)getSystemService(
      Context.SENSOR_SERVICE);
    myProximitySensor = mySensorManager.getDefaultSensor(
      Sensor.TYPE_PROXIMITY);

    if (myProximitySensor == null){
     ProximitySensor.setText("No Proximity Sensor!"); 
    }else{
     ProximitySensor.setText(myProximitySensor.getName());
     ProximityMax.setText("Maximum Range: "
       + String.valueOf(myProximitySensor.getMaximumRange()));
     mySensorManager.registerListener(proximitySensorEventListener,
       myProximitySensor,
       SensorManager.SENSOR_DELAY_NORMAL);
    }
}

SensorEventListener proximitySensorEventListener
= new SensorEventListener(){

@Override
public void onAccuracyChanged(Sensor sensor, int accuracy) {
 // TODO Auto-generated method stub

}

@Override
public void onSensorChanged(SensorEvent event) {
// TODO Auto-generated method stub

if(event.sensor.getType()==Sensor.TYPE_PROXIMITY){
 ProximityReading.setText("Proximity Sensor Reading:"
   + String.valueOf(event.values[0]));
 }
 }
  };
 }

In the above code, when the event.values[0] = 0, it means my hand is hover at the sensor. However, I need my sensor to detect a hand wave. How do I do it? Thanks.

Answer 1

Please try this code:

    private SensorManager sensorManager;
    private Sensor proximitySensor;

    private final int WAVE_TIME = 2000;
    private final int WAVE_NEEDED_MOVEMENTS = 3;
    private long lastWaveTime = 0;
    private float lastSensorValue;
    private float maxSensorValue;
    private float numOfMovements = 0; 


        public void onCreate() {
              super.onCreate();

              sensorManager = (SensorManager) getSystemService(Context.SENSOR_SERVICE);
              proximitySensor = sensorManager.getDefaultSensor(Sensor.TYPE_PROXIMITY);
              sensorManager.registerListener(proximitySensorEventListener, proximitySensor,SensorManager.SENSOR_DELAY_NORMAL);
              maxSensorValue = proximitySensor.getMaximumRange();
        }

        @Override
        public void onSensorChanged(SensorEvent event) {

             if(lastWaveTime + WAVE_TIME > System.currentTimeMillis()) {
                 System.out.println("Reset timing...");
                 lastWaveTime = System.currentTimeMillis();
                 numOfMovements = 0;
                 lastSensorValue = event.values[0];
             } else if((event.values[0] != maxSensorValue && lastSensorValue == maxSensorValue) || (event.values[0] == maxSensorValue && lastSensorValue != maxSensorValue) ){
                 numOfMovements++;
                 if(numOfMovements == WAVE_NEEDED_MOVEMENTS) {
                     System.out.println("WAVE EVENT");
                     lastWaveTime = System.currentTimeMillis();
                     numOfMovements = 0;
                 }
             }

        }