package com.softwinner.performance.frameratetest;

import android.Manifest;

import android.bluetooth.BluetoothAdapter;

import android.bluetooth.BluetoothDevice;

import android.content.BroadcastReceiver;

import android.content.Context;

import android.content.Intent;

import android.content.IntentFilter;

import android.content.pm.PackageManager;

import android.os.Bundle;

import android.support.v4.app.ActivityCompat;

import android.support.v7.app.AppCompatActivity;

import android.util.Log;

import android.widget.Toast;

import java.util.Set;

public class MainActivity extends AppCompatActivity {

    private BluetoothAdapter mBluetoothAdapter = BluetoothAdapter.getDefaultAdapter();

    private String mLogTag = "bluetoothtest";

    private final BroadcastReceiver mReceiver = new BroadcastReceiver() {

        @Override

        public void onReceive(Context context, Intent intent) {

            String action = intent.getAction();

            if(BluetoothDevice.ACTION_FOUND.equals(action)){

                BluetoothDevice remoteDevice = intent.getParcelableExtra(BluetoothDevice.EXTRA_DEVICE);

                    Log.i(mLogTag,remoteDevice.getName() + " address: " + remoteDevice.getAddress());

            }

            else if(BluetoothAdapter.ACTION_DISCOVERY_FINISHED.equals(action)){

                Log.i(mLogTag,"search finished");

            }

        }

    };

    @Override

    protected void onCreate(Bundle savedInstanceState) {

        super.onCreate(savedInstanceState);

        setContentView(R.layout.activity_main);

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.KILL_BACKGROUND_PROCESSES) != PackageManager.PERMISSION_GRANTED) {

            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.KILL_BACKGROUND_PROCESSES},);

        }

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.WRITE_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {

            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.WRITE_EXTERNAL_STORAGE},);

        }

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.READ_EXTERNAL_STORAGE) != PackageManager.PERMISSION_GRANTED) {

            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.READ_EXTERNAL_STORAGE},);

        }

        if (ActivityCompat.checkSelfPermission(this, Manifest.permission.ACCESS_COARSE_LOCATION) != PackageManager.PERMISSION_GRANTED) {

            ActivityCompat.requestPermissions(this, new String[]{Manifest.permission.ACCESS_COARSE_LOCATION},);

        }

        searchDevices();

    }

    private void searchDevices(){

        if(mBluetoothAdapter == null){

            Log.i(mLogTag,"device not support bluetooth");

            Toast.makeText(MainActivity.this,"device not support bluetooth",Toast.LENGTH_SHORT).show();

            return;

        }

        if(!mBluetoothAdapter.isEnabled()){

            mBluetoothAdapter.enable();

            mBluetoothAdapter.cancelDiscovery();

            Toast.makeText(MainActivity.this,"bluetooth has open",Toast.LENGTH_SHORT).show();

        }

        IntentFilter filter = new IntentFilter(BluetoothDevice.ACTION_FOUND);

        filter.addAction(BluetoothAdapter.ACTION_DISCOVERY_FINISHED);

        filter.setPriority(Integer.MAX_VALUE);

        registerReceiver(mReceiver,filter);

        mBluetoothAdapter.startDiscovery();

        try {Thread.sleep();} catch (InterruptedException e) {e.printStackTrace();}

//        showBoundDevices();

    }

    private void showBoundDevices(){

//        List<Map<String, String>> mBoundDevicesList = new ArrayList<>();

        Set<BluetoothDevice> pairDevices = mBluetoothAdapter.getBondedDevices();

        if(pairDevices.size() > ){

            for(BluetoothDevice boundDevice : pairDevices){

                System.out.println(boundDevice.getName() + " " + boundDevice.getAddress());

                Log.i(mLogTag, boundDevice.getName()+ " " + boundDevice.getAddress());

            }

        }

    }

}

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

    package="com.softwinner.performance.frameratetest">

    <uses-permission android:name="android.permission.KILL_BACKGROUND_PROCESSES"/>

    <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE"/>

    <uses-permission android:name="android.permission.BLUETOOTH"/>

    <uses-permission android:name="android.permission.BLUETOOTH_ADMIN"/>

    <uses-permission android:name="android.permission.ACCESS_FINE_LOCATION" />

    <uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION" />

    <application

        android:allowBackup="true"

        android:icon="@mipmap/ic_launcher"

        android:label="@string/app_name"

        android:supportsRtl="true"

        android:theme="@style/AppTheme">

        <activity android:name="com.softwinner.performance.frameratetest.MainActivity">

            <intent-filter>

                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />

            </intent-filter>

        </activity>

    </application>

</manifest>