Kotlin 取 MAC 地址

package com.example.ybs.myapplication

import android.annotation.SuppressLint
import android.net.wifi.WifiManager
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import kotlinx.android.synthetic.main.activity_main.*
import java.net.NetworkInterface

class MainActivity : AppCompatActivity() {

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main);

        var mac = getLocalMacAddress();
        txtInfo.text = mac;
    }

    @SuppressLint("WifiManagerLeak")
    fun getLocalMacAddress():String{
         var Context = this.applicationContext;
        var wifi= getSystemService(WIFI_SERVICE) as WifiManager;
        var info=wifi.connectionInfo;
        return info.macAddress;
    }


}

 需要权限

    <permission android:name="android.permission.ACCESS_WIFI_STATE" />
    <permission android:name="android.permission.CHANGE_WIFI_STATE" />