How to refresh app upon shaking the device?

Question

I need to add a shake feature that will refresh my Android application.

All I find of documentation involves implementing the SensorListener, but Eclips

Answer 1

Shaker.java

    import java.util.ArrayList;
    import android.content.Context;
    import android.hardware.Sensor;
    import android.hardware.SensorEvent;
    import android.hardware.SensorEventListener;
    import android.hardware.SensorManager;

    public class Shaker implements SensorEventListener{

        private static final String SENSOR_SERVICE = Context.SENSOR_SERVICE;
        private SensorManager sensorMgr;
        private Sensor mAccelerometer;
        private boolean accelSupported;
        private long timeInMillis;
        private long threshold;
        private OnShakerTreshold listener;
        ArrayList valueStack;

        public Shaker(Context context, OnShakerTreshold listener, long timeInMillis, long threshold) {
            try {
                this.timeInMillis = timeInMillis;
                this.threshold = threshold;
                this.listener = listener;
                if (timeInMillis<100){
                    throw new Exception("timeInMillis < 100ms");
                }
                valueStack = new ArrayList((int)(timeInMillis/100));
                sensorMgr = (SensorManager) context.getSystemService(SENSOR_SERVICE);
                mAccelerometer = sensorMgr.getDefaultSensor(Sensor.TYPE_ACCELEROMETER);

            } catch (Exception e){
                e.printStackTrace();
            }
        }

        public void start() {
            try {
                accelSupported = sensorMgr.registerListener(this, mAccelerometer, SensorManager.SENSOR_DELAY_GAME); 
                if (!accelSupported) {
                    stop();
                    throw new Exception("Sensor is not supported");
                }
            } catch (Exception e){
                e.printStackTrace();
            }
        }

        public void stop(){
            try {
                sensorMgr.unregisterListener(this, mAccelerometer);
            } catch (Exception e){
                e.printStackTrace();
            }
        }

        @Override
        protected void finalize() throws Throwable {
            try {
                stop();
            } catch (Exception e){
                e.printStackTrace();
            }
            super.finalize();
        }

        long lastUpdate = 0;
        private float last_x;
        private float last_y;
        private float last_z;

public void onSensorChanged(SensorEvent event) {
    try {
        if (event.sensor == mAccelerometer) {
            long curTime = System.currentTimeMillis();
            if ((curTime-lastUpdate)>getNumberOfMeasures()){

                lastUpdate = System.currentTimeMillis();
                float[] values = event.values;
                if (valueStack.size()>(int)getNumberOfMeasures())
                    valueStack.remove(0);
                float x = (int)(values[SensorManager.DATA_X]);
                float y = (int)(values[SensorManager.DATA_Y]);
                float z = (int)(values[SensorManager.DATA_Z]);
                float speed = Math.abs((x+y+z) - (last_x + last_y + last_z));

                valueStack.add(speed);

                String posText = String.format("X:%4.0f Y:%4.0f Z:%4.0f", (x-last_x), (y-last_y), (z-last_z));

                last_x = (x);
                last_y = (y);
                last_z = (z);

                float sumOfValues = 0;
                float avgOfValues = 0;

                for (float f : valueStack){
                        sumOfValues = (sumOfValues+f);
                }
                avgOfValues = sumOfValues/(int)getNumberOfMeasures();

                if (avgOfValues>=threshold){
                    listener.onTreshold();
                    valueStack.clear();
                }

                System.out.println(String.format("M: %+4d A: %5.0f V: %4.0f %s", valueStack.size(),avgOfValues,speed,posText));

            }
        }
    } catch (Exception e){
        e.printStackTrace();
    }
}


        private long getNumberOfMeasures() {
            return timeInMillis/100;
        }

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

        public interface OnShakerTreshold {
            public void onTreshold();
        }
    }

MainActivity.java

public class MainActivity extends Activity implements OnShakerTreshold{


    private Shaker s;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        s = new Shaker(getApplicationContext(), this, 5000, 20);
        // 5000 = 5 second of shaking
        // 20 = minimal threshold (very angry shaking :D)
        // beware screen rotation reset counter
    }

    @Override
    protected void onResume() {
        s.start();
        super.onResume();
    }

    @Override
    protected void onPause() {
        s.stop();
        super.onPause();
    }

    public void onTreshold() {
        System.out.println("FIRE LISTENER");
        RingtoneManager.getRingtone(getApplicationContext(), RingtoneManager.getDefaultUri(RingtoneManager.TYPE_NOTIFICATION)).play();
    }


}

Have fun.