Android 6.0 Kotlin 蓝牙扫描

package com.arci.myapplication

import android.app.Activity
import android.os.Bundle
import android.support.design.widget.Snackbar
import android.support.v7.app.AppCompatActivity
import android.view.Menu
import android.view.MenuItem
import android.view.View

import kotlinx.android.synthetic.main.activity_main.*
import android.widget.TextView
import kotlinx.android.synthetic.main.content_main.*
import android.bluetooth.BluetoothManager
import android.content.Context
import android.bluetooth.BluetoothAdapter
import android.widget.Toast
import android.content.Intent
import android.text.method.TextKeyListener.clear
import android.bluetooth.BluetoothDevice
import android.bluetooth.le.BluetoothLeScanner
import android.content.BroadcastReceiver
import android.content.IntentFilter

class MainActivity : AppCompatActivity() {
    val REQUEST_BLUETOOTH_TURN_ON = 1
    lateinit var bluetoothAdapter: BluetoothAdapter
    lateinit var bluetoothManager: BluetoothManager

    var bluetoothDeviceList = ArrayList<BluetoothDevice>()

    // 广播接收发现蓝牙设备
    private val mReceiver = object : BroadcastReceiver() {

        override fun onReceive(context: Context, intent: Intent) {
            val action = intent.action

            if (BluetoothAdapter.ACTION_DISCOVERY_STARTED == action) {
                //Log.d(FragmentActivity.TAG, "开始扫描...")
                Toast.makeText(context.applicationContext, "蓝牙扫描开始", Toast.LENGTH_SHORT).show()
            }

            if (BluetoothDevice.ACTION_FOUND == action) {
                val device = intent.getParcelableExtra<BluetoothDevice>(BluetoothDevice.EXTRA_DEVICE)
                if (device != null) {
                    // 添加到ListView的Adapter。
                    //mAdapter.add("设备名:" + device.name + "\n设备地址:" + device.address)
                    //mAdapter.notifyDataSetChanged()
                    Toast.makeText(context.applicationContext, device.name + ": " + device.address, Toast.LENGTH_SHORT).show()
                }
            }

            if (BluetoothAdapter.ACTION_DISCOVERY_FINISHED == action) {
                //Log.d(FragmentActivity.TAG, "扫描结束.")
                Toast.makeText(context.applicationContext, "蓝牙扫描结束", Toast.LENGTH_SHORT).show()
            }
        }
    }

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

        fab.setOnClickListener { view ->
            Snackbar.make(view, "Replace with your own action", Snackbar.LENGTH_LONG)
                    .setAction("Action", null).show()
        }
        // 注册广播接收器。
        // 接收蓝牙发现
        val filterFound = IntentFilter(BluetoothDevice.ACTION_FOUND)
        registerReceiver(mReceiver, filterFound)

        val filterStart = IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_STARTED)
        registerReceiver(mReceiver, filterStart)

        val filterFinish = IntentFilter(BluetoothAdapter.ACTION_DISCOVERY_FINISHED)
        registerReceiver(mReceiver, filterFinish)

        //蓝牙管理，这是系统服务可以通过getSystemService(BLUETOOTH_SERVICE)的方法获取实例
        bluetoothManager = getSystemService(Context.BLUETOOTH_SERVICE) as BluetoothManager
        //通过蓝牙管理实例获取适配器，然后通过扫描方法（scan）获取设备(device)
        bluetoothAdapter = bluetoothManager.adapter
        if (!bluetoothAdapter.isEnabled) {
            val bluetoothTurnOn = Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE)
            startActivityForResult(bluetoothTurnOn, REQUEST_BLUETOOTH_TURN_ON)
        } else {
            bluetoothAdapter.startDiscovery();
        }
    }

    override fun onActivityResult(requestCode: Int, resultCode: Int, data: Intent?) {
        super.onActivityResult(requestCode, resultCode, data)
        when (requestCode) {
            REQUEST_BLUETOOTH_TURN_ON->{
                when (resultCode) {
                    RESULT_OK->{
                        //TextView1.text = "蓝牙开启成功"
                        Toast.makeText(this.applicationContext, "蓝牙开启成功", Toast.LENGTH_SHORT).show()
                        bluetoothAdapter.startDiscovery()
                    }
                    RESULT_CANCELED->{
                        //TextView1.text = "蓝牙开启失败"
                        Toast.makeText(this.applicationContext, "蓝牙开启失败", Toast.LENGTH_SHORT).show()
                    }
                }
            }
        }
    }
    override fun onCreateOptionsMenu(menu: Menu): Boolean {
        // Inflate the menu; this adds items to the action bar if it is present.
        menuInflater.inflate(R.menu.menu_main, menu)
        return true
    }

    override fun onOptionsItemSelected(item: MenuItem): Boolean {
        // Handle action bar item clicks here. The action bar will
        // automatically handle clicks on the Home/Up button, so long
        // as you specify a parent activity in AndroidManifest.xml.
        return when (item.itemId) {
            R.id.action_settings -> true
            else -> super.onOptionsItemSelected(item)
        }
    }
}