一、使用startForegroundService()或startService（）启用service

**Activity

 //启动service
val intent: Intent = Intent(ServiceActivity@this,MyService::class.java)
//Build.VERSION_CODES.O = 26
// Android8以后，不允许后台启动Service
if(Build.VERSION.SDK_INT >= 26){startForegroundService(intent)}else{startService(intent)}

 **Service

package com.example.buju.serviceimport android.app.NotificationChannel
import android.app.NotificationManager
import android.app.Service
import android.content.Context
import android.content.Intent
import android.graphics.BitmapFactory
import android.os.Build
import android.os.IBinder
import android.util.Log
import androidx.core.app.NotificationCompatclass MyService:Service() {override fun onCreate() {super.onCreate()Log.e("MyService","onCreate")initNotification()}// 初始化通知（安卓8.0之后必须实现）private fun initNotification() {val channelName = "channelName"val channelId = "channelId"if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){// 发送通知，把service置于前台val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager// 从Android 8.0开始，需要注册通知通道if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {val channel = NotificationChannel(channelId, channelName, NotificationManager.IMPORTANCE_HIGH)notificationManager.createNotificationChannel(channel)}// 页面跳转val intent = Intent(applicationContext,ServiceActivity::class.java)val pendingIntent = PendingIntent.getActivity(this, 0, intent,PendingIntent.FLAG_UPDATE_CURRENT)// 创建通知并配置相应属性val notification = NotificationCompat.Builder(this, channelId).setSmallIcon(android.R.drawable.star_off)//小图标一定需要设置,否则会报错(如果不设置它启动服务前台化不会报错,但是你会发现这个通知不会启动),如果是普通通知,不设置必然报错.setLargeIcon(BitmapFactory.decodeResource(getResources(), android.R.drawable.star_on)).setContentTitle("通知标题")// 标题.setContentText("通知内容")// 内容.setPriority(NotificationCompat.PRIORITY_DEFAULT).setContentIntent(pendingIntent)// 设置跳转.setWhen(System.currentTimeMillis()).setAutoCancel(false).setOngoing(true).build()// 注意第一个参数不能为0startForeground(1, notification)}}override fun onBind(intent: Intent?): IBinder? {Log.e("MyService","onBind")return null}override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {Log.e("MyService","onStartCommand")return super.onStartCommand(intent, flags, startId)}override fun onUnbind(intent: Intent?): Boolean {Log.e("MyService","onUnbind")return super.onUnbind(intent)}override fun onDestroy() {super.onDestroy()Log.e("MyService","onDestroy")//停止的时候销毁前台服务。stopForeground(true);}}

注意该方法不会调用onBind（）和onUnbind（）

二、绑定启用service

**Activity

package com.example.bujuimport android.content.ComponentName
import android.content.Context
import android.content.Intent
import android.content.ServiceConnection
import android.os.Bundle
import android.os.IBinder
import android.util.Log
import android.view.View
import android.widget.Button
import androidx.appcompat.app.AppCompatActivity
import com.example.buju.service.MyServiceclass ServiceActivity:AppCompatActivity() {private var myBinder:MyService.MyBinder? = nulllateinit var startBtn:Buttonlateinit var stopBtn:Buttonlateinit var getBtn:Buttonoverride fun onCreate(savedInstanceState: Bundle?) {super.onCreate(savedInstanceState)setContentView(R.layout.activity_service)initControls()}/*** 控件初始化* */private fun initControls(){startBtn = findViewById(R.id.startBtn)startBtn.setOnClickListener(btnClick)stopBtn = findViewById(R.id.stopBtn)stopBtn.setOnClickListener(btnClick)getBtn = findViewById(R.id.getBtn)getBtn.setOnClickListener(btnClick)}/*** service 连接* */private val connection = object:ServiceConnection{//Activity与Service连接成功时回调该方法override fun onServiceConnected(name: ComponentName?, service: IBinder?) {Log.e("MyService","---------Service 成功连接----------")myBinder = service as MyService.MyBinder}// Activity与Service断开连接时回调该方法override fun onServiceDisconnected(name: ComponentName?) {Log.e("MyService","---------Service 断开连接----------")}}/*** 点击事件* */val btnClick:(View)->Unit = {when(it.id) {R.id.startBtn -> {// 绑定serviceval intent: Intent = Intent(ServiceActivity@this,MyService::class.java)bindService(intent,connection,Context.BIND_AUTO_CREATE)}R.id.stopBtn ->{// 解除绑定unbindService(connection)}R.id.getBtn ->{// 获取service传递过来的数据Log.e("MyService","getCount=${myBinder?.getCount()}")}else ->{}}}override fun finish() {super.finish()overridePendingTransition(R.anim.slide_no,R.anim.slide_out_from_bottom)}override fun onDestroy() {super.onDestroy()// 解除绑定unbindService(connection)}}

**Service

package com.example.buju.serviceimport android.app.NotificationChannel
import android.app.NotificationManager
import android.app.Service
import android.content.Context
import android.content.Intent
import android.graphics.BitmapFactory
import android.os.Binder
import android.os.Build
import android.os.IBinder
import android.util.Log
import androidx.core.app.NotificationCompatclass MyService:Service() {/*** 用于传递参数* */private var count:Int = 0private var myBinder:MyBinder = MyBinder()inner class MyBinder: Binder(){fun getCount():Int?{return count}}override fun onCreate() {super.onCreate()Log.e("MyService","onCreate")Thread(Runnable {Thread.sleep(1000)count=100}).start()initNotification()}// 初始化通知（安卓8.0之后必须实现）private fun initNotification() {val channelName = "channelName"val channelId = "channelId"if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O){// 发送通知，把service置于前台val notificationManager = getSystemService(Context.NOTIFICATION_SERVICE) as NotificationManager// 从Android 8.0开始，需要注册通知通道if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {val channel = NotificationChannel(channelId, channelName, NotificationManager.IMPORTANCE_HIGH)notificationManager.createNotificationChannel(channel)}val notification = NotificationCompat.Builder(this, channelId).setSmallIcon(android.R.drawable.star_off)//小图标一定需要设置,否则会报错(如果不设置它启动服务前台化不会报错,但是你会发现这个通知不会启动),如果是普通通知,不设置必然报错.setLargeIcon(BitmapFactory.decodeResource(getResources(), android.R.drawable.star_on)).setContentTitle("通知标题")// 标题.setContentText("通知内容")// 内容.setWhen(System.currentTimeMillis()).setAutoCancel(false).setOngoing(true).build()// 注意第一个参数不能为0startForeground(1, notification)}}override fun onBind(intent: Intent?): IBinder? {Log.e("MyService","onBind")return myBinder}override fun onStartCommand(intent: Intent?, flags: Int, startId: Int): Int {Log.e("MyService","onStartCommand")return super.onStartCommand(intent, flags, startId)}override fun onUnbind(intent: Intent?): Boolean {Log.e("MyService","onUnbind")return super.onUnbind(intent)}override fun onDestroy() {super.onDestroy()Log.e("MyService","onDestroy")//停止的时候销毁前台服务。stopForeground(true);}}