利用Android的传感器改变背景色彩

利用Android的传感器改变背景颜色

最近许多程序都使用了android机硬件的传感器(Sensor)，其中传感器又分为好几种，比如方向，加速计，温度，磁场等，但是不同机型并不保证包括所有类型的传感器。不过大部分机子都包括加速计，下面写一个简单的demo来演示利用加速计改变应用背景颜色。

1.Activity:

public class MainActivity extends Activity implements SensorEventListener {

	private SensorManager sensorManager;
	private long lastUpdate;
	private View view;
	private static final int[] colors = { Color.RED, Color.BLACK, Color.BLUE,
			Color.CYAN, Color.YELLOW, Color.GRAY, Color.GREEN };
	private Random r = new Random();

	@Override
	protected void onCreate(Bundle savedInstanceState) {
		requestWindowFeature(Window.FEATURE_NO_TITLE);
		getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
				WindowManager.LayoutParams.FLAG_FULLSCREEN);

		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		view = findViewById(R.id.parent);

		sensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
		lastUpdate = System.currentTimeMillis();
	}

	@Override
	public void onSensorChanged(SensorEvent event) {
		if (event.sensor.getType() == Sensor.TYPE_ACCELEROMETER) {
			getAccelerometer(event);
		}
	}

	private void getAccelerometer(SensorEvent event) {
		float[] values = event.values;
		// x轴,y轴,z轴加速度
		float x = values[0];
		float y = values[1];
		float z = values[2];

		float accelationSquareRoot = (x * x + y * y + z * z)
				/ (SensorManager.GRAVITY_EARTH * SensorManager.GRAVITY_EARTH);
		long actualTime = System.currentTimeMillis();
		if (accelationSquareRoot >= 2) {
			if (actualTime - lastUpdate < 500) {
				return;
			}
			lastUpdate = actualTime;
			Toast.makeText(this, "设备甩了一下", Toast.LENGTH_SHORT).show();
			view.setBackgroundColor(colors[r.nextInt(colors.length)]);
		}
	}

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

	@Override
	protected void onResume() {
		super.onResume();
		// 注册监听器
		sensorManager.registerListener(this,
				sensorManager.getDefaultSensor(Sensor.TYPE_ACCELEROMETER),
				SensorManager.SENSOR_DELAY_NORMAL);
	}

	@Override
	protected void onPause() {
		super.onPause();
		// 注销监听器
		sensorManager.unregisterListener(this);
	}

}

2. layout文件:

<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:id="@+id/parent"
    android:layout_width="fill_parent"
    android:layout_height="fill_parent" >

</LinearLayout>

3. 使用传感器不需要在清单文件中添加权限。

4.甩几下手机：

... Hope it helps you.