1.MainActivity.java

package com.sensor.guoxing.sensor;

import android.hardware.Sensor;
import android.hardware.SensorEvent;
import android.hardware.SensorEventListener;
import android.hardware.SensorManager;
import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.widget.TextView;

public class MainActivity extends AppCompatActivity implements SensorEventListener {
    private TextView tvProximity;
    private SensorManager mSensorManager;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        tvProximity = (TextView) findViewById(R.id.tv_accelerometer);
        //获取传感器SensorManager对象
        mSensorManager = (SensorManager) getSystemService(SENSOR_SERVICE);
    }
    /**
     * 传感器精度变化时回调
     */
    @Override
    public void onAccuracyChanged(Sensor sensor, int accuracy) {
    }
    /**
     * 传感器数据变化时回调
     */
    @Override
    public void onSensorChanged(SensorEvent event) {
        //判断传感器类别
        switch (event.sensor.getType()) {
            case Sensor.TYPE_PROXIMITY://临近传感器
                tvProximity.setText(String.valueOf(event.values[0]));
                break;
            default:
                break;
        }
    }
    /**
     * 界面获取焦点，按钮可以点击时回调
     */
    protected void onResume() {
        super.onResume();
        //注册临近传感器
        mSensorManager.registerListener(this,
                mSensorManager.getDefaultSensor(Sensor.TYPE_PROXIMITY),
                SensorManager.SENSOR_DELAY_UI);
    }
    /**
     * 暂停Activity，界面获取焦点，按钮可以点击时回调
     */
    @Override
    protected void onPause() {
        super.onPause();
        mSensorManager.unregisterListener(this);
    }

}

2.activity_main.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.constraint.ConstraintLayout 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"
    tools:context="com.sensor.guoxing.sensor.MainActivity">


    <TextView
        android:id="@+id/tv_accelerometer"
        android:layout_width="fill_parent"
        android:layout_height="fill_parent"
        android:text=""
        tools:layout_editor_absoluteX="43dp"
        tools:layout_editor_absoluteY="16dp" />
</android.support.constraint.ConstraintLayout>