android - 使用摇动 Action 从加速度计获取方向

Question

我制作了 Android 应用程序，使用加速度计摇动一次即可播放下一首歌曲。

现在我想要我的应用程序，如果在右侧摇动手机，它应该播放下一首歌曲，或者如果在左侧摇动播放上一首歌曲，我可以用当时发现的轴逻辑来做到这一点吗？如果可能的话，摇动 Action 如何将轴放入运动检测方法中以了解移动设备摇动的方向。如果有人对此有逻辑，请帮助我被困在这里。

Answer 1

我对此进行了一些深入研究，并能够自己解决它。但在发布答案时我 found this answer作者:Basil，它比我的实现解释得更好。所以，我发现它更有帮助。

what he did

在onSensorChanged中，每当设备收到新值时，它都会在一段延迟后将这些值存储到变量中。之后将新值与以前的值进行完美比较。这导致计算设备震动的方向。如果答案仍然不清楚，请告诉我。

public class ShakeActivity extends Activity implements SensorListener {
// For shake motion detection.
private SensorManager sensorMgr;
private long lastUpdate = -1;
private float x, y, z;
private float last_x, last_y, last_z;
private static final int SHAKE_THRESHOLD = 800;

protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);

setContentView(R.layout.main);
// start motion detection
sensorMgr = (SensorManager) getSystemService(SENSOR_SERVICE);
boolean accelSupported = sensorMgr.registerListener(this,
    SensorManager.SENSOR_ACCELEROMETER,
    SensorManager.SENSOR_DELAY_GAME);

    if (!accelSupported) {
        // on accelerometer on this device
        sensorMgr.unregisterListener(this,
                SensorManager.SENSOR_ACCELEROMETER);
    }
}

protected void onPause() {
    if (sensorMgr != null) {
        sensorMgr.unregisterListener(this,
                SensorManager.SENSOR_ACCELEROMETER);
        sensorMgr = null;
    }
    super.onPause();
}

public void onAccuracyChanged(int arg0, int arg1) {
// TODO Auto-generated method stub
}

public void onSensorChanged(int sensor, float[] values) {
    if (sensor == SensorManager.SENSOR_ACCELEROMETER) {
        long curTime = System.currentTimeMillis();
        // only allow one update every 100ms.
        if ((curTime - lastUpdate) > 100) {
        long diffTime = (curTime - lastUpdate);
        lastUpdate = curTime;

        x = values[SensorManager.DATA_X];
        y = values[SensorManager.DATA_Y];
        z = values[SensorManager.DATA_Z];

        if(Round(x,4)>10.0000){
            Log.d("sensor", "X Right axis: " + x);
            Toast.makeText(this, "Right shake detected", Toast.LENGTH_SHORT).show();
        }
        else if(Round(x,4)<-10.0000){
            Log.d("sensor", "X Left axis: " + x);
            Toast.makeText(this, "Left shake detected", Toast.LENGTH_SHORT).show();
        }

        float speed = Math.abs(x+y+z - last_x - last_y - last_z) / diffTime * 10000;

        // Log.d("sensor", "diff: " + diffTime + " - speed: " + speed);
        if (speed > SHAKE_THRESHOLD) {
            //Log.d("sensor", "shake detected w/ speed: " + speed);
            //Toast.makeText(this, "shake detected w/ speed: " + speed, Toast.LENGTH_SHORT).show();
        }
        last_x = x;
        last_y = y;
        last_z = z;
        }
    }
}

public static float Round(float Rval, int Rpl) {
float p = (float)Math.pow(10,Rpl);
Rval = Rval * p;
float tmp = Math.round(Rval);
return (float)tmp/p;
}
}