public void onSensorChanged(SensorEvent event) { long currentTime = System.currentTimeMillis(); long diffTime = currentTime - mLastUpdateTime; if (diffTime > UPDATE_INTERVAL) { if (mLastUpdateTime != 0) { float x = event.values[0]; float y = event.values[1]; float z = event.values[2]; float deltaX = x - mLastX; float deltaY = y - mLastY; float deltaZ = z - mLastZ; float delta = FloatMath.sqrt(deltaX * deltaX + deltaY * deltaY + deltaZ * deltaZ) / diffTime * 10000; if (delta > SHAKE_THRESHOLD) { if (!shaken) { shaken = true; finish(); } if (listener != null) { listener.onShake(); } } mLastX = x; mLastY = y; mLastZ = z; } mLastUpdateTime = currentTime; } }