package com.example.sz.proximitytest;

import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.support.v7.app.AppCompatActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity {
 private static final String TAG = "MainActivity";
 private SensorManager mSensorManager=null;
 private Sensor mSensor=null;
 private TextView textView1=null;
 private TextView textView2=null;
 private TextView textView3=null;
 private Button button1=null;
 private Button button2=null;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
 super.onCreate(savedInstanceState);
 setContentView(R.layout.activity_main);
 textView1 = (TextView) findViewById(R.id.textView1);
 textView2 = (TextView) findViewById(R.id.textView2);
 textView3 = (TextView) findViewById(R.id.textView3);
 /*獲取系統(tǒng)服務(wù)（SENSOR_SERVICE）返回一個(gè)SensorManager對(duì)象*/
 mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
 /*通過(guò)SensorManager獲取相應(yīng)的（接近傳感器）Sensor類型對(duì)象*/
 mSensor = mSensorManager.getDefaultSensor(Sensor.TYPE_PROXIMITY);
 /*注冊(cè)相應(yīng)的SensorService*/
 button1 = (Button) findViewById(R.id.button1);
 button1.setOnClickListener(new Button.OnClickListener() {

  @Override
  public void onClick(View arg0) {
  mSensorManager.registerListener(mSensorEventListener, mSensor
   , SensorManager.SENSOR_DELAY_NORMAL);
  }
 });
 /* 銷毀相應(yīng)的SensorService
  * 很關(guān)鍵的部分，注意，說(shuō)明文檔中提到，即使Activity不可見的時(shí)候，感應(yīng)器依然會(huì)繼續(xù)工作
  * 所以一定要關(guān)閉觸發(fā)器，否則將消耗用戶大量電量*/
 button2 = (Button) findViewById(R.id.button2);
 button2.setOnClickListener(new Button.OnClickListener() {

  @Override
  public void onClick(View v) {
  mSensorManager.unregisterListener(mSensorEventListener, mSensor);
  }
 });
 }

 /*聲明一個(gè)SensorEventListener對(duì)象用于偵聽Sensor事件，并重載onSensorChanged方法*/
 private final SensorEventListener mSensorEventListener = new SensorEventListener() {

 @Override
 public void onSensorChanged(SensorEvent event) {
  Log.e(TAG, "onSensorChanged: -----0------"+event.values[0]);
  Log.e(TAG, "onSensorChanged: ------1-----"+event.values[1]);
  Log.e(TAG, "onSensorChanged: --------2---"+event.values[2]);




  if (event.sensor.getType() == Sensor.TYPE_PROXIMITY) {
  /*接近傳感器檢測(cè)物體與聽筒的距離，單位是厘米。*/
  //這里要注意，正常都是取第一位的值，但我碰到一個(gè)取第二位的
  float distance1 = event.values[0];
  float distance2 = event.values[1];
  float distance3 = event.values[2];
  textView1.setText("[0]距離："+String.valueOf(distance1) + "cm");
  textView2.setText("[1]距離："+String.valueOf(distance2) + "cm");
  textView3.setText("[2]距離："+String.valueOf(distance3) + "cm");
  }
 }

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

 }
 };


}

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
 xmlns:app="http://schemas.android.com/apk/res-auto"
 xmlns:tools="http://schemas.android.com/tools"
 android:layout_width="match_parent"
 android:layout_height="match_parent"
 android:gravity="center"
 android:orientation="vertical"
 tools:context=".MainActivity">

 <TextView
 android:id="@+id/textView1"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:text="Hello World!" />

 <Button
 android:id="@+id/button1"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_marginTop="20dp"
 android:text="打開" />

 <Button
 android:id="@+id/button2"
 android:layout_width="wrap_content"
 android:layout_height="wrap_content"
 android:layout_marginTop="20dp"
 android:text="關(guān)閉" />
</LinearLayout>