class HelloIntentService : IntentService("HelloIntentService") {

    override fun onHandleIntent(intent: Intent?) {
        try {
            Thread.sleep(5000)
        } catch (e: InterruptedException) {
            Thread.currentThread().interrupt()
        }

    }
}

val pendingIntent: PendingIntent =
        Intent(this, ExampleActivity::class.java).let { notificationIntent ->
            PendingIntent.getActivity(this, 0, notificationIntent, 0)
        }

// 안드로이드 O 이상에서는 CHANNEL을 따로 만들어줘야 합니다.
val notification: Notification = Notification.Builder(this, CHANNEL_DEFAULT_IMPORTANCE)
        .setContentTitle(getText(R.string.notification_title))
        .setContentText(getText(R.string.notification_message))
        .setSmallIcon(R.drawable.icon)
        .setContentIntent(pendingIntent)
        .setTicker(getText(R.string.ticker_text))
        .build()

startForeground(ONGOING_NOTIFICATION_ID, notification)

package com.byjw.testbindservice.service

import android.app.Service
import android.content.Intent
import android.os.IBinder
import android.util.Log

class MyService : Service() {

    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        Log.i("JW_TEST", "onStartCommand()")

        return START_STICKY // 서비스가 강제종료될 시 재생성합니다.
    }

    override fun onBind(intent: Intent): IBinder? {
        return null // 바인딩 하지 않기 때문에 null 반환
    }
}

package com.byjw.testbindservice.service

import android.content.Intent
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import com.byjw.testbindservice.R
import kotlinx.android.synthetic.main.activity_service.*

class MyServiceActivity : AppCompatActivity() {

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

        this.btn_service.setOnClickListener {
            val intent = Intent(this, MyService::class.java)
            startService(intent)
        }

    }
}

package com.byjw.testbindservice.binder

import android.app.Service
import android.content.Intent
import android.os.Binder
import android.os.IBinder
import android.util.Log
import java.util.*

class BindingService : Service() {

    private val localBinder = LocalBinder()

    private val generator = Random()

    val randomNumber: Int
        get() = generator.nextInt(100)

    inner class LocalBinder : Binder() {
        fun getService(): BindingService = this@BindingService
    }

    override fun onBind(intent: Intent): IBinder {
        return localBinder
    }

}

package com.byjw.testbindservice.binder

import android.content.ComponentName
import android.content.Context
import android.content.Intent
import android.content.ServiceConnection
import android.support.v7.app.AppCompatActivity
import android.os.Bundle
import android.os.IBinder
import android.widget.Toast
import com.byjw.testbindservice.R
import kotlinx.android.synthetic.main.activity_binding.*

class BindingActivity : AppCompatActivity() {

    private lateinit var bindingService: BindingService
    private var bound: Boolean = false

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

        // 버튼이 눌렀을 때 서비스와 상호작용하도록 리스너 등록
        this.btn_binding.setOnClickListener {
            if (bound) {
                val num: Int = bindingService.randomNumber
                Toast.makeText(this, "number: $num", Toast.LENGTH_SHORT).show()
            }
        }
    }

    override fun onStart() {
        super.onStart()

        // 바인딩
        val intent = Intent(this, BindingService::class.java)
        bindService(intent, serviceConnection, Context.BIND_AUTO_CREATE)
    }

    override fun onStop() {
        super.onStop()

        // 언바인딩
        unbindService(serviceConnection)
        bound = false
    }

    private val serviceConnection = object : ServiceConnection {

        // 서비스와 연결되었을 때
        override fun onServiceConnected(className: ComponentName, service: IBinder) {
            val binder = service as BindingService.LocalBinder
            bindingService = binder.getService()
            bound = true
        }

        // 서비스와 연결해제되었을 때
        override fun onServiceDisconnected(arg0: ComponentName) {
            bound = false
        }
    }
}

package com.byjw.testbindservice.messenger

import android.app.Service
import android.content.Context
import android.content.Intent
import android.os.Handler
import android.os.IBinder
import android.os.Message
import android.os.Messenger
import android.widget.Toast

const val MSG_SAY_HELLO = 1

class MessengerService : Service() {

    private lateinit var messenger: Messenger

    override fun onBind(intent: Intent): IBinder? {
        Toast.makeText(applicationContext, "binding", Toast.LENGTH_SHORT).show()
        messenger = Messenger(IncomingHandler(this))
        return messenger.binder
    }

    internal class IncomingHandler(
        context: Context,
        private val applicationContext: Context = context.applicationContext
    ) : Handler() {
        override fun handleMessage(msg: Message) {
            when (msg.what) {
                MSG_SAY_HELLO ->
                    Toast.makeText(applicationContext, "hello!", Toast.LENGTH_SHORT).show()
                else -> super.handleMessage(msg)
            }
        }
    }

}

package com.byjw.testbindservice.messenger

import android.content.ComponentName
import android.content.Context
import android.content.Intent
import android.content.ServiceConnection
import android.os.*
import android.support.v7.app.AppCompatActivity
import com.byjw.testbindservice.R
import kotlinx.android.synthetic.main.activity_messenger.*

class MessengerActivity : AppCompatActivity() {

    private var messenger: Messenger? = null
    private var bound: Boolean = false

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

        this.btn_messenger.setOnClickListener {
            sayHello()
        }

    }


    private fun sayHello() {
        if (!bound) return

        val message: Message = Message.obtain(null, MSG_SAY_HELLO, 0, 0)
        try {
            messenger?.send(message)
        } catch (e: RemoteException) {
            e.printStackTrace()
        }

    }

    private val serviceConnection = object : ServiceConnection {
        // 서비스와 연결되었을 때
        override fun onServiceConnected(className: ComponentName, service: IBinder) {
            messenger = Messenger(service)
            bound = true
        }
        // 서비스와 연결해제되었을 때
        override fun onServiceDisconnected(className: ComponentName) {
            messenger = null
            bound = false
        }
    }

    override fun onStart() {
        super.onStart()

        val intent = Intent(this, MessengerService::class.java)
        bindService(intent, serviceConnection, Context.BIND_AUTO_CREATE)
    }

    override fun onStop() {
        super.onStop()

        if (bound) {
            unbindService(serviceConnection)
            bound = false
        }
    }


}

package com.byjw.testbindservice.foregroundService

import android.app.*
import android.content.Context
import android.content.Intent
import android.os.Build
import android.os.IBinder
import android.support.v4.app.NotificationCompat

const val CHANNEL_ID = "default_channel_id"
const val CHANNEL_NAME = "default_channel_name"

class MyForegroundService : Service() {

    override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {
        val notificationIntent = Intent(this, ForegroundServiceActivity::class.java)
        val pendingIntent: PendingIntent = PendingIntent.getActivity(this, 0, notificationIntent, 0)

        val builder: NotificationCompat.Builder

        // 안드로이드 O 버전 이상에서부터는 채널 ID를 지정해주어야 합니다.
        builder = if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager

            notificationManager.createNotificationChannel(
                NotificationChannel(CHANNEL_ID, CHANNEL_NAME, NotificationManager.IMPORTANCE_DEFAULT)
            )

            NotificationCompat.Builder(this, CHANNEL_ID)
        } else {
            NotificationCompat.Builder(this)
        }

        val notification = builder
            .setContentTitle("Title")
            .setContentText("Body")
            .setContentIntent(pendingIntent)
            .build()

        // startForeground()에 지정하는 정수 ID는 0이면 안됩니다.
        startForeground(1, notification)

        return START_STICKY
    }

    override fun onBind(intent: Intent): IBinder? {
        return null
    }

}

package com.byjw.testbindservice.foregroundService

import android.content.Intent
import android.os.Build
import android.os.Bundle
import android.support.v7.app.AppCompatActivity
import com.byjw.testbindservice.R
import kotlinx.android.synthetic.main.activity_foreground_service.*

class ForegroundServiceActivity : AppCompatActivity() {

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

        this.btn_foreground_service.setOnClickListener {
            val intent = Intent(this, MyForegroundService::class.java)

            // 안드로이드 O 이상에서는 startForegroundService()로 호출해야합니다.
            if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
                startForegroundService(intent)
            } else {
                startService(intent)
            }
        }

    }
}