MainActivity：

package com.demo

import android.app.NotificationManager
import android.os.Bundle
import android.util.Log
import androidx.appcompat.app.AppCompatActivity
import com.gorhaf.ball.databinding.ActivityMainBinding
import kotlinx.coroutines.CoroutineScope
import kotlinx.coroutines.Dispatchers
import kotlinx.coroutines.Job
import kotlinx.coroutines.SupervisorJob
import kotlinx.coroutines.cancel
import kotlinx.coroutines.delay
import kotlinx.coroutines.isActive
import kotlinx.coroutines.launch

class MainActivity : AppCompatActivity() {
    private val TAG = MainActivity::class.simpleName

    private lateinit var binding: ActivityMainBinding

    private lateinit var notificationManager: NotificationManager
    private var mainCoroutineScope = CoroutineScope(SupervisorJob() + Dispatchers.IO)
    private var updateNotificationJob: Job? = null

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)

        // Example of a call to a native method
        // binding.sampleText.text = stringFromJNI()

        // 初始化数据
        initData()
        // 初始化事件
        initEvent()
    }

    override fun onDestroy() {
        super.onDestroy()
    }

    private fun initData() {
        notificationManager = getSystemService(NotificationManager::class.java)
        LikeNotificationChannel.create(notificationManager)
        TopNotificationChannel.create(notificationManager)
        HotNotificationChannel.create(notificationManager)
    }

    private fun initEvent() {
        binding.mainSendBtn.setOnClickListener { send() }
        binding.mainCancelBtn.setOnClickListener { cancel() }
        binding.mainUpdateBtn.setOnClickListener { update() }
    }

    private fun send() {
        // LikeNotificationChannel.send(notificationManager, this)
        TopNotificationChannel.send(notificationManager, this)
    }

    private fun cancel() {
        // LikeNotificationChannel.cancel(notificationManager)
        TopNotificationChannel.cancel(notificationManager)
        mainCoroutineScope.cancel("取消通知")
    }

    private fun update() {
        // mainCoroutineScope.cancel("取消之前的任务")
        Log.i(TAG, "update: ${mainCoroutineScope.isActive}")
        if (updateNotificationJob != null && updateNotificationJob!!.isActive) {
            updateNotificationJob!!.cancel("取消之前的任务，开启新的任务")
        }
        if (!mainCoroutineScope.isActive) {
            mainCoroutineScope = CoroutineScope(SupervisorJob() + Dispatchers.IO)
        }
        updateNotificationJob = mainCoroutineScope.launch {
            while (true) {
                TopNotificationChannel.update(notificationManager, this@MainActivity)
                delay(1000)
            }
        }
    }

    /**
     * A native method that is implemented by the 'ball' native library,
     * which is packaged with this application.
     */
    external fun stringFromJNI(): String

    companion object {
        // Used to load the 'ball' library on application startup.
        init {
            System.loadLibrary("ball")
        }
    }
}

LikeNotificationChannel：

package com.demo

import android.app.NotificationChannel
import android.app.NotificationManager
import android.app.PendingIntent
import android.content.Context
import android.content.Intent
import android.graphics.BitmapFactory
import androidx.core.app.NotificationCompat
import com.demo.music.MusicActivity

object LikeNotificationChannel {
    var id: String = "like"
    var name: String = "喜欢"
    var importance: Int = NotificationManager.IMPORTANCE_HIGH
    val notificationChannel: NotificationChannel = NotificationChannel(id, name, importance)

    val notifyId: Int = 1

    fun create(notificationManager: NotificationManager) {
        notificationManager.createNotificationChannel(notificationChannel)
    }

    fun send(notificationManager: NotificationManager, context: Context) {
        val intent = PendingIntent.getActivity(
            context,
            0,
            Intent(context, MusicActivity::class.java),
            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
        )

        val notification = NotificationCompat.Builder(context, LikeNotificationChannel.id)
            .setContentTitle("This is like content title")
            .setContentText("This is like content text")
            .setContentInfo("This is like content info")
            .setContentIntent(intent)
            .setSmallIcon(R.drawable.ic_launcher_foreground)
            .setLargeIcon(
                BitmapFactory.decodeResource(
                    context.resources,
                    R.drawable.ic_launcher_background
                )
            )
            .setPriority(NotificationCompat.PRIORITY_HIGH)
            .setDefaults(NotificationCompat.DEFAULT_ALL)
            .setVisibility(NotificationCompat.VISIBILITY_PUBLIC)
            .setAutoCancel(false)
            .setOngoing(true)
            .build()

        notificationManager.notify(notifyId, notification)
    }

    fun cancel(notificationManager: NotificationManager) {
        notificationManager.cancel(notifyId)
    }
}

TopNotificationChannel：

package com.demo

import android.app.NotificationChannel
import android.app.NotificationManager
import android.app.PendingIntent
import android.content.Context
import android.content.Intent
import android.graphics.BitmapFactory
import androidx.core.app.NotificationCompat

object TopNotificationChannel {
    var id: String = "top"
    var name: String = "排行榜"
    var importance: Int = NotificationManager.IMPORTANCE_HIGH
    val notificationChannel: NotificationChannel = NotificationChannel(id, name, importance)

    val notifyId: Int = 1

    fun create(notificationManager: NotificationManager) {
        notificationManager.createNotificationChannel(notificationChannel)
    }

    fun send(notificationManager: NotificationManager, context: Context) {
        val intent = PendingIntent.getActivity(
            context,
            0,
            Intent(context, MainActivity::class.java),
            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
        )

        val notification = NotificationCompat.Builder(context, LikeNotificationChannel.id)
            .setContentTitle("当前时间")
            .setContentText("${System.currentTimeMillis()}")
            .setContentInfo("This is like content info")
            .setContentIntent(intent)
            .setSmallIcon(R.drawable.ic_launcher_foreground)
            .setLargeIcon(
                BitmapFactory.decodeResource(
                    context.resources,
                    R.drawable.ic_launcher_background
                )
            )
            .setPriority(NotificationCompat.PRIORITY_HIGH)
            .setDefaults(NotificationCompat.DEFAULT_ALL)
            .setVisibility(NotificationCompat.VISIBILITY_PUBLIC)
            .setAutoCancel(false)
            .setOngoing(true)
            .build()

        notificationManager.notify(notifyId, notification)
    }

    fun cancel(notificationManager: NotificationManager) {
        notificationManager.cancel(notifyId)
    }

    fun update(notificationManager: NotificationManager, context: Context) {
        val intent = PendingIntent.getActivity(
            context,
            0,
            Intent(context, MainActivity::class.java),
            PendingIntent.FLAG_UPDATE_CURRENT or PendingIntent.FLAG_IMMUTABLE
        )

        val notification = NotificationCompat.Builder(context, LikeNotificationChannel.id)
            .setContentTitle("当前时间")
            .setContentText("${System.currentTimeMillis()}")
            .setContentInfo("This is like content info")
            .setContentIntent(intent)
            .setSmallIcon(R.drawable.ic_launcher_foreground)
            .setLargeIcon(
                BitmapFactory.decodeResource(
                    context.resources,
                    R.drawable.ic_launcher_background
                )
            )
            .setPriority(NotificationCompat.PRIORITY_HIGH)
            .setDefaults(NotificationCompat.DEFAULT_ALL)
            .setVisibility(NotificationCompat.VISIBILITY_PUBLIC)
            .setAutoCancel(false)
            .setOngoing(true)
            .build()

        notificationManager.notify(notifyId, notification)
    }
}

HotNotificationChannel：

package com.demo

import android.app.NotificationChannel
import android.app.NotificationManager

object HotNotificationChannel {
    var id: String = "hot"
    var name: String = "热点新闻"
    var importance: Int = NotificationManager.IMPORTANCE_HIGH
    val notificationChannel: NotificationChannel = NotificationChannel(id, name, importance)

    fun create(notificationManager: NotificationManager) {
        notificationManager.createNotificationChannel(notificationChannel)
    }
}