Android_通过传感器抓小偷

Posted 2022-06-23 pre_eminent

package com.beyond.phonestolen;

import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.media.AudioManager;
import android.media.MediaPlayer;
import android.os.Bundle;
import android.app.Activity;
import android.widget.Toast;

public class MainActivity extends Activity 
	//传感器管理器
	private SensorManager sm;
	//距离传感器
	private Sensor sensor;
	
	@Override
	protected void onCreate(Bundle savedInstanceState) 
		super.onCreate(savedInstanceState);
		setContentView(R.layout.activity_main);
		//1,通过获取系统服务，得到传感器管理器
		sm=(SensorManager) getSystemService(SENSOR_SERVICE);
		//2,通过传感器管理器获取指定的距离传感器
		sensor=sm.getDefaultSensor(Sensor.TYPE_PROXIMITY);
		//3,通过传感器管理器注册监听器,监听距离传感器的感应事件
		sm.registerListener(new MyListener(), sensor, SensorManager.SENSOR_DELAY_GAME);
	
	private class MyListener implements SensorEventListener
		@Override
		public void onSensorChanged(SensorEvent event) 
			float distance=event.values[0];
			//System.out.println(val[0]);
			Toast.makeText(MainActivity.this, ""+distance, 0).show();
			//当手机在裤袋里面时，距离为0
			if (distance<1.0f) 
				return;
			
			//当手机脱离裤袋的时候，距离为1，播放音乐
			playMusic();
			
		
		private void playMusic() 
			// 播放音乐
			MediaPlayer mPlayer=MediaPlayer.create(MainActivity.this, R.drawable.alarm);
			mPlayer.setAudiostreamType(AudioManager.STREAM_MUSIC);
			try 
				mPlayer.prepare();
			 catch (Exception e) 
				e.printStackTrace();
			
			//理论上应该异步准备，在准备完成的回调函数中启动播放器
			mPlayer.start();
		
		@Override
		public void onAccuracyChanged(Sensor sensor, int accuracy)