使用 Kotlin 在 Android 中创建通知

步骤

创建通知

NotificationUtils、EggTimerViewModel、EggTimerFragment

基本通知

在 NotificationManager 中实现一个扩展 fun sendN - 无需重写代码即可发送 Ns
- 创建一个扩展乐趣来发送消息
- 为通知创建内容意图以启动此活动
- 创建 PendingIntent
- 设置内容意图
- 取消所有通知

获取 NotificationCompat.Builder 的实例以构建通知
为 Builder 设置标题、文本和图标
呼叫通知
使用新的通知渠道

添加样式
向 Builder 添加样式
添加贪睡动作

设置优先级

// NotificationUtils.kt

package com.example.android.eggtimernotifications.util

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.example.android.eggtimernotifications.MainActivity
import com.example.android.eggtimernotifications.R
import com.example.android.eggtimernotifications.receiver.SnoozeReceiver

// Notification ID.
private val NOTIFICATION_ID = 0
private val REQUEST_CODE = 0
private val FLAGS = 0

// Step 1.1 extension function to send messages (GIVEN)
/**
 * Builds and delivers the notification.
 *
 * @param context, activity context.
 */
fun NotificationManager.sendNotification(messageBody: String, applicationContext: Context) {
    // Create the content intent for the notification, which launches
    // this activity
    // TODO: Step 1.11 create intent

    // TODO: Step 1.12 create PendingIntent

    // TODO: Step 2.0 add style

    // TODO: Step 2.2 add snooze action

    // TODO: Step 1.2 get an instance of NotificationCompat.Builder
    // Build the notification
    val builder = NotificationCompat.Builder(
        applicationContext,
        applicationContext.getString(R.string.egg_notification_channel_id)
    )

    // TODO: Step 1.8 use the new 'breakfast' notification channel

    // TODO: Step 1.3 set title, text and icon to builder
        .setSmallIcon(R.drawable.cooked_egg)
        .setContentTitle(applicationContext
            .getString(R.string.notification_title))
        .setContentText(messageBody)

    // TODO: Step 1.13 set content intent

        // TODO: Step 2.1 add style to builder

        // TODO: Step 2.3 add snooze action

        // TODO: Step 2.5 set priority

    // TODO: Step 1.4 call notify
    notify(NOTIFICATION_ID, builder.build())
}

// TODO: Step 1.14 Cancel all notifications

获取 NotificationManager 的实例并调用sendNotification和EggTimerViewModel

package com.example.android.eggtimernotifications.ui

import android.app.*
import android.content.Context
import android.content.Intent
import android.os.CountDownTimer
import android.os.SystemClock
import androidx.core.app.AlarmManagerCompat
import androidx.core.content.ContextCompat
import androidx.lifecycle.*
import com.example.android.eggtimernotifications.receiver.AlarmReceiver
import com.example.android.eggtimernotifications.R
import com.example.android.eggtimernotifications.util.sendNotification
import kotlinx.coroutines.*

class EggTimerViewModel(private val app: Application) : AndroidViewModel(app) {

    private val REQUEST_CODE = 0
    private val TRIGGER_TIME = "TRIGGER_AT"

    private val minute: Long = 60_000L
    private val second: Long = 1_000L

    private val timerLengthOptions: IntArray
    private val notifyPendingIntent: PendingIntent

    private val alarmManager = app.getSystemService(Context.ALARM_SERVICE) as AlarmManager
    private var prefs = app.getSharedPreferences(
                        "com.example.android.eggtimernotifications",
                        Context.MODE_PRIVATE
        )
    private val notifyIntent = Intent(app, AlarmReceiver::class.java)

    private val _timeSelection = MutableLiveData<Int>()
    val timeSelection: LiveData<Int>
        get() = _timeSelection

    private val _elapsedTime = MutableLiveData<Long>()
    val elapsedTime: LiveData<Long>
        get() = _elapsedTime

    private var _alarmOn = MutableLiveData<Boolean>()
    val isAlarmOn: LiveData<Boolean>
        get() = _alarmOn

    private lateinit var timer: CountDownTimer

    init {
        _alarmOn.value = PendingIntent.getBroadcast(
            getApplication(),
            REQUEST_CODE,
            notifyIntent,
            PendingIntent.FLAG_NO_CREATE
        ) != null

        notifyPendingIntent = PendingIntent.getBroadcast(
            getApplication(),
            REQUEST_CODE,
            notifyIntent,
            PendingIntent.FLAG_UPDATE_CURRENT
        )

        timerLengthOptions = app.resources.getIntArray(R.array.minutes_array)

        //If alarm is not null, resume the timer back for this alarm
        if (_alarmOn.value!!) {
            createTimer()
        }

    }

    /**
     * Turns on or off the alarm
     *
     * @param isChecked, alarm status to be set.
     */
    fun setAlarm(isChecked: Boolean) {
        when (isChecked) {
            true -> timeSelection.value?.let { startTimer(it) }
            false -> cancelNotification()
        }
    }

    /**
     * Sets the desired interval for the alarm
     *
     * @param timerLengthSelection, interval timerLengthSelection value.
     */
    fun setTimeSelected(timerLengthSelection: Int) {
        _timeSelection.value = timerLengthSelection
    }

    /**
     * Creates a new alarm, notification and timer
     */
    private fun startTimer(timerLengthSelection: Int) {
        _alarmOn.value?.let {
            if (!it) {
                _alarmOn.value = true
                val selectedInterval = when (timerLengthSelection) {
                    0 -> second * 10 //For testing only
                    else ->timerLengthOptions[timerLengthSelection] * minute
                }
                val triggerTime = SystemClock.elapsedRealtime() + selectedInterval

                // Step 1.5 get an instance of NotificationManager and call sendNotification
                val notificationManager = ContextCompat.getSystemService(                       
                    app,                                                                        
                    NotificationManager::class.java                                             
                ) as NotificationManager                                                        
                notificationManager.sendNotification(app.getString(R.string.timer_running), app)

                              // Step 1.15 call cancel notification

                AlarmManagerCompat.setExactAndAllowWhileIdle(
                    alarmManager,
                    AlarmManager.ELAPSED_REALTIME_WAKEUP,
                    triggerTime,
                    notifyPendingIntent
                )

                viewModelScope.launch {
                    saveTime(triggerTime)
                }
            }
        }
        createTimer()
    }

    /**
     * Creates a new timer
     */
    private fun createTimer() {
        viewModelScope.launch {
            val triggerTime = loadTime()
            timer = object : CountDownTimer(triggerTime, second) {
                override fun onTick(millisUntilFinished: Long) {
                    _elapsedTime.value = triggerTime - SystemClock.elapsedRealtime()
                    if (_elapsedTime.value!! <= 0) {
                        resetTimer()
                    }
                }

                override fun onFinish() {
                    resetTimer()
                }
            }
            timer.start()
        }
    }

    /**
     * Cancels the alarm, notification and resets the timer
     */
    private fun cancelNotification() {
        resetTimer()
        alarmManager.cancel(notifyPendingIntent)
    }

    /**
     * Resets the timer on screen and sets alarm value false
     */
    private fun resetTimer() {
        timer.cancel()
        _elapsedTime.value = 0
        _alarmOn.value = false
    }

    private suspend fun saveTime(triggerTime: Long) =
        withContext(Dispatchers.IO) {
            prefs.edit().putLong(TRIGGER_TIME, triggerTime).apply()
        }

    private suspend fun loadTime(): Long =
        withContext(Dispatchers.IO) {
            prefs.getLong(TRIGGER_TIME, 0)
        }
}

通知渠道

创建一个扩展 fun createChannel（并在 onCreate 中调用它）
- 创建 NotificationChannel 实例 - 传递 id、名称和重要性
- 在 NotificationChannel obj 上，设置道具 - enableLights、lightColor、enableVibration、通道描述
- 通过调用 getSystemService 获取 NotificationManager 的实例
- 在 NotificationManager 上调用 createNotificationChannel 并传递 NotificationChannel obj。
- 要创建频道，请调用此createChannel分机。乐趣在onCreate乐趣。
- NotificationUtils → build：验证你之前设置的频道id是否正确
- 拉动状态栏，观察通知标题、内容和图标是否与您在前面步骤中设置的一样。
- 要验证新创建的频道，请关闭应用并找到应用图标。长按应用程序图标并选择应用程序信息。

// EggTimerFragment.kt

package com.example.android.eggtimernotifications.ui

import android.app.NotificationChannel
import android.app.NotificationManager
import android.graphics.Color
import android.os.Build
import android.os.Bundle
import android.util.Log
import android.view.LayoutInflater
import android.view.View
import android.view.ViewGroup
import android.widget.Toast
import androidx.databinding.DataBindingUtil
import androidx.fragment.app.Fragment
import androidx.lifecycle.ViewModelProvider
import com.example.android.eggtimernotifications.R
import com.example.android.eggtimernotifications.databinding.FragmentEggTimerBinding
import com.google.firebase.messaging.FirebaseMessaging

class EggTimerFragment : Fragment() {

    private val TOPIC = "breakfast"

    override fun onCreateView(
        inflater: LayoutInflater, container: ViewGroup?,
        savedInstanceState: Bundle?
    ): View? {

        val binding: FragmentEggTimerBinding = DataBindingUtil.inflate(
            inflater, R.layout.fragment_egg_timer, container, false
        )

        val viewModel = ViewModelProvider(this).get(EggTimerViewModel::class.java)

        binding.eggTimerViewModel = viewModel
        binding.lifecycleOwner = this.viewLifecycleOwner

        // Step 1.7 call create channel
        createChannel(
            getString(R.string.egg_notification_channel_id),
            getString(R.string.egg_notification_channel_name)
        )

        return binding.root
    }

    private fun createChannel(channelId: String, channelName: String) {
        // Step 1.6 START create a channel
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val notificationChannel = NotificationChannel(
                channelId,
                channelName,
                // Change importance
                NotificationManager.IMPORTANCE_LOW
            )

            notificationChannel.enableLights(true)
            notificationChannel.lightColor = Color.RED
            notificationChannel.enableVibration(true)
            notificationChannel.description = "Time for breakfast!"

            val notificationManager = requireActivity().getSystemService(
                NotificationManager::class.java
            )
            notificationManager.createNotificationChannel(notificationChannel)

        } else {
            Log.d(TAG, "VERSION.SDK_INT < O")
            Toast.makeText(context, "VERSION.SDK_INT < O", Toast.LENGTH_SHORT).show()
        }

        // Step 1.6 END create a channel

    }

    companion object {
        private const val TAG = "EggTimerFragment"
        fun newInstance() = EggTimerFragment()
    }
}

添加新通知

报警接收器

向您的应用添加通知

使用 AlarmReceiver 创建另一个通知
- 创建一个继承 BroadcastReceiver 的 AlarmReceiver 类
- 通过调用 getSystemService 获取 NotificationManager 的实例并在其上调用sendNotification

package com.example.android.eggtimernotifications.receiver

import android.app.NotificationManager
import android.content.BroadcastReceiver
import android.content.Context
import android.content.Intent
import android.widget.Toast
import androidx.core.content.ContextCompat
import com.example.android.eggtimernotifications.R
import com.example.android.eggtimernotifications.util.sendNotification

class AlarmReceiver: BroadcastReceiver() {

    override fun onReceive(context: Context, intent: Intent) {
        // Step 1.10 remove toast (since we're now sending a notification for the same)
        // Toast.makeText(context, context.getText(R.string.eggs_ready), Toast.LENGTH_SHORT).show()

        // TODO: Step 1.9 add call to sendNotification
        val notificationManager = ContextCompat.getSystemService(
            context,
            NotificationManager::class.java
        ) as NotificationManager

                notificationManager.sendNotification(
            context.getText(R.string.eggs_ready).toString(),
            context
        )

    }

}

使用 PendingIntent 从通知返回到应用程序

通知工具

添加内容意图

点击通知导航回应用程序

创建意图
创建待处理的意图
通过在 NotificationBuilder 上调用 setContentIntent 将待处理的意图传递给通知
要让通知在您点击它时自行消失，因为它会将您带到应用程序，请将 setAutoCancel 设置为 true

package com.example.android.eggtimernotifications.util

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.example.android.eggtimernotifications.MainActivity
import com.example.android.eggtimernotifications.R
import com.example.android.eggtimernotifications.receiver.SnoozeReceiver

// Notification ID.
private val NOTIFICATION_ID = 0
private val REQUEST_CODE = 0
private val FLAGS = 0

// Step 1.1 extension function to send messages (GIVEN)
/**
 * Builds and delivers the notification.
 *
 * @param context, activity context.
 */
fun NotificationManager.sendNotification(messageBody: String, applicationContext: Context) {
    // Create the content intent for the notification, which launches
    // this activity
    // Step 1.11 create intent
    val contentIntent = Intent(applicationContext, MainActivity::class.java)

    // Step 1.12 create PendingIntent
    val contentPendingIntent = PendingIntent.getActivity(
        applicationContext,
        NOTIFICATION_ID,
        contentIntent,
        PendingIntent.FLAG_UPDATE_CURRENT
    )

    // TODO: Step 2.0 add style

    // TODO: Step 2.2 add snooze action

    // Step 1.2 get an instance of NotificationCompat.Builder
    // Build the notification
    val builder = NotificationCompat.Builder(
        applicationContext,
        applicationContext.getString(R.string.egg_notification_channel_id)
    )

    // TODO: Step 1.8 use the new 'breakfast' notification channel

    // Step 1.3 set title, text and icon to builder
        .setSmallIcon(R.drawable.cooked_egg)
        .setContentTitle(applicationContext
            .getString(R.string.notification_title))
        .setContentText(messageBody)

    // Step 1.13 set content intent
        .setContentIntent(contentPendingIntent)
        .setAutoCancel(true)

        // TODO: Step 2.1 add style to builder

        // TODO: Step 2.3 add snooze action

        // TODO: Step 2.5 set priority

    // Step 1.4 call notify
    notify(NOTIFICATION_ID, builder.build())
}

// TODO: Step 1.14 Cancel all notifications

使用 cancelAll 清除以前的通知

NotificationUtils, EggTimerViewModel

取消通知

创建一个扩展乐趣 cancelNotifications
- 在 NotificationManager 上添加一个调用 cancelAll 的扩展 fun
通知工具
```
funNotificationManager.cancelNotifications() {
    cancelAll()
}
```
在 startTimer fun 中调用扩展 fun cancelNotifications

EggTimerViewModel
```
notificationManager.cancelNotifications()
```

样式化您的通知

通知工具

在 BigPictureStyle 中设置通知样式

使用 BitmapFactory 从资源中加载图像
创建一个新的 BigPictureStyle bigPicStyle并设置您的图像
要在通知展开时让大图标消失，请将 bigLargeIcon 设置为 null
将新样式bigPicStyle设置为 NotificationBuilder
要在通知折叠时将图像显示为较小的图标，请在构建器上将图像设置为 setLargeIcon

package com.example.android.eggtimernotifications.util

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.example.android.eggtimernotifications.MainActivity
import com.example.android.eggtimernotifications.R
import com.example.android.eggtimernotifications.receiver.SnoozeReceiver

// Notification ID.
private const val NOTIFICATION_ID = 0
private const val REQUEST_CODE = 0
private const val FLAGS = 0

// Step 1.1 extension function to send messages (GIVEN)
/**
 * Builds and delivers the notification.
 *
 * @param context, activity context.
 */
fun NotificationManager.sendNotification(messageBody: String, applicationContext: Context) {
    // Create the content intent for the notification, which launches
    // this activity
    // Step 1.11 create intent
    val contentIntent = Intent(applicationContext, MainActivity::class.java)

    // Step 1.12 create PendingIntent
    val contentPendingIntent = PendingIntent.getActivity(
        applicationContext,
        NOTIFICATION_ID,
        contentIntent,
        PendingIntent.FLAG_UPDATE_CURRENT
    )

    // Step 2.0 add style
    val eggImage =  BitmapFactory.decodeResource(
            applicationContext.resources,
            R.drawable.cooked_egg
    )

    val bigPicStyle = NotificationCompat.BigPictureStyle()
            .bigPicture(eggImage)
            .bigLargeIcon(null)

    // TODO: Step 2.2 add snooze action

    // Step 1.2 get an instance of NotificationCompat.Builder
    // Build the notification
    val builder = NotificationCompat.Builder(
        applicationContext,
        applicationContext.getString(R.string.egg_notification_channel_id)
    )

    // TODO: Step 1.8 use the new 'breakfast' notification channel

    // Step 1.3 set title, text and icon to builder
        .setSmallIcon(R.drawable.cooked_egg)
        .setContentTitle(applicationContext
            .getString(R.string.notification_title))
        .setContentText(messageBody)

    // Step 1.13 set content intent
        .setContentIntent(contentPendingIntent)
        .setAutoCancel(true)

    // Step 2.1 add style to builder
            .setStyle(bigPicStyle)
            .setLargeIcon(eggImage)

    // TODO: Step 2.3 add snooze action

    // TODO: Step 2.5 set priority

    // TODO: Step 1.4 call notify
    notify(NOTIFICATION_ID, builder.build())
}

// Step 1.14 Cancel all notifications
fun NotificationManager.cancelNotifications() {
    cancelAll()
}

添加贪睡动作

贪睡接收器，NotificationUtils

安排新通知并删除已延后的通知

获取 NotificationManager 的实例

package com.example.android.eggtimernotifications.receiver

import android.app.AlarmManager
import android.app.NotificationManager
import android.app.PendingIntent
import android.content.BroadcastReceiver
import android.content.Context
import android.content.Intent
import android.os.SystemClock
import android.text.format.DateUtils
import androidx.core.app.AlarmManagerCompat
import androidx.core.content.ContextCompat

class SnoozeReceiver: BroadcastReceiver() {
    private val REQUEST_CODE = 0

    override fun onReceive(context: Context, intent: Intent) {
        val triggerTime = SystemClock.elapsedRealtime() + DateUtils.MINUTE_IN_MILLIS

        val notifyIntent = Intent(context, AlarmReceiver::class.java)
        val notifyPendingIntent = PendingIntent.getBroadcast(
            context,
            REQUEST_CODE,
            notifyIntent,
            PendingIntent.FLAG_UPDATE_CURRENT
        )

        val alarmManager = context.getSystemService(Context.ALARM_SERVICE) as AlarmManager
        AlarmManagerCompat.setExactAndAllowWhileIdle(
            alarmManager,
            AlarmManager.ELAPSED_REALTIME_WAKEUP,
            triggerTime,
            notifyPendingIntent
        )

        val notificationManager = ContextCompat.getSystemService(
                context,
                NotificationManager::class.java
        ) as NotificationManager
        notificationManager.cancelAll()
    }

}

当用户使用 PendingIntent 轻按贪睡按钮时，设置新警报以在 60 秒后发布新通知

创建意图
创建一个 PendingIntent
在 NotificationBuilder 上调用 addAction fun

package com.example.android.eggtimernotifications.util

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.example.android.eggtimernotifications.MainActivity
import com.example.android.eggtimernotifications.R
import com.example.android.eggtimernotifications.receiver.SnoozeReceiver

// Notification ID.
private const val NOTIFICATION_ID = 0
private const val REQUEST_CODE = 0
private const val FLAGS = 0

// Step 1.1 extension function to send messages (GIVEN)
/**
 * Builds and delivers the notification.
 *
 * @param context, activity context.
 */
fun NotificationManager.sendNotification(messageBody: String, applicationContext: Context) {
    // Create the content intent for the notification, which launches
    // this activity
    // Step 1.11 create intent
    val contentIntent = Intent(applicationContext, MainActivity::class.java)

    // Step 1.12 create PendingIntent
    val contentPendingIntent = PendingIntent.getActivity(
        applicationContext,
        NOTIFICATION_ID,
        contentIntent,
        PendingIntent.FLAG_UPDATE_CURRENT
    )

    // Step 2.0 add style
    val eggImage =  BitmapFactory.decodeResource(
            applicationContext.resources,
            R.drawable.cooked_egg
    )

    val bigPicStyle = NotificationCompat.BigPictureStyle()
            .bigPicture(eggImage)
            .bigLargeIcon(null)

    // Step 2.2 add snooze action
    val snoozeIntent = Intent(applicationContext, SnoozeReceiver::class.java)
    val snoozePendingIntent = PendingIntent.getBroadcast(
            applicationContext,
            REQUEST_CODE,
            snoozeIntent,
            FLAGS
    )

    // Step 1.2 get an instance of NotificationCompat.Builder
    // Build the notification
    val builder = NotificationCompat.Builder(
        applicationContext,
        applicationContext.getString(R.string.egg_notification_channel_id)
    )

    // TODO: Step 1.8 use the new 'breakfast' notification channel

    // Step 1.3 set title, text and icon to builder
        .setSmallIcon(R.drawable.cooked_egg)
        .setContentTitle(applicationContext
            .getString(R.string.notification_title))
        .setContentText(messageBody)

    // Step 1.13 set content intent
        .setContentIntent(contentPendingIntent)
        .setAutoCancel(true)

    // Step 2.1 add style to builder
            .setStyle(bigPicStyle)
            .setLargeIcon(eggImage)

    // Step 2.3 add snooze action
            .addAction(
                    R.drawable.egg_icon,
                    applicationContext.getString(R.string.snooze),
                    snoozePendingIntent
            )

    // TODO: Step 2.5 set priority

    // Step 1.4 call notify
    notify(NOTIFICATION_ID, builder.build())
}

// Step 1.14 Cancel all notifications
fun NotificationManager.cancelNotifications() {
    cancelAll()
}

改变重要性

EggTimerFragment、NotificationUtils

设置图片

// NotificationUtils()

    // Step 2.0 add style
    val eggImage =  BitmapFactory.decodeResource(
            applicationContext.resources,
            R.drawable.cooked_egg
    )

    val bigPicStyle = NotificationCompat.BigPictureStyle()
            .bigPicture(eggImage)
            .bigLargeIcon(null)

**********************************************************************************

    val builder = NotificationCompat.Builder(
        applicationContext,
        applicationContext.getString(R.string.egg_notification_channel_id)
    )
                        ...
    // Step 2.1 add style to builder
            .setStyle(bigPicStyle)
            .setLargeIcon(eggImage)

将重要性从低到高

NotificationManager → 重要性

...

class EggTimerFragment : Fragment() {

    ...

    private fun createChannel(channelId: String, channelName: String) {
        // Step 1.6 START create a channel
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val notificationChannel = NotificationChannel(
                channelId,
                channelName,
                // Change importance
                NotificationManager.IMPORTANCE_HIGH
            )

            notificationChannel.enableLights(true)
            notificationChannel.lightColor = Color.RED
            notificationChannel.enableVibration(true)
            notificationChannel.description = "Time for breakfast!"

            val notificationManager = requireActivity().getSystemService(
                NotificationManager::class.java
            )
            notificationManager.createNotificationChannel(notificationChannel)

        } else {
            Log.d(TAG, "VERSION.SDK_INT < O")
            Toast.makeText(context, "VERSION.SDK_INT < O", Toast.LENGTH_SHORT).show()
        }

        // Step 1.6 END create a channel

    }

    ...
}

将 PRIORITY_HIGH 添加到通知构建器对象

要支持运行 API 级别 25 或更低级别的设备，您必须使用 NotificationCompat 类中的常量为每个通知调用 setPriority。为了解决这个问题，我们正在执行上述操作。

// *NotificationUtils.kt*

fun NotificationManager.sendNotification(messageBody: String, applicationContext: Context) {
    ...

    // Step 1.2 get an instance of NotificationCompat.Builder
    // Build the notification
    val builder = NotificationCompat.Builder(
        applicationContext,
        applicationContext.getString(R.string.egg_notification_channel_id)
    )

    ...

    // Step 2.5 set priority
            .setPriority(NotificationCompat.PRIORITY_HIGH)

      ...
}

...

通知徽章

EggTimerFragment

禁用徽章

在 NotificationChannel obj 上将 setShowBadge 设置为 false。

// *EggTimerFragment.kt*

private fun createChannel(channelId: String, channelName: String) {
        // Step 1.6 START create a channel
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O) {
            val notificationChannel = NotificationChannel(
                channelId,
                channelName,
                // Change importance
                NotificationManager.IMPORTANCE_HIGH
            )
            // Step 2.6 Disable badges for this channel
                    .apply {
                        setShowBadge(false)
                    }
                        ...
                }
}

链接：https://dev.to/apigeoneer/creating-notifications-in-android-with-kotlin-56fi

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救了他两次的神仙让他今天三更去死
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道士缉凶录：失踪的卖姜人
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港岛之恋（遗憾婚礼）
正文为了忘掉前任，我火速办了婚礼，结果婚礼上，老公的妹妹穿的比我还像新娘。我一直安慰自己，他们只是感情好，可当我...
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恶毒庶女顶嫁案：这布局不是一般人想出来的
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城市分裂传说
那天，我揣着相机与录音，去河边找鬼。笑死，一个胖子当着我的面吹牛，可吹牛的内容都是我干的。我是一名探鬼主播，决...
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双鸳鸯连环套：你想象不到人心有多黑
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万荣杀人案实录
序言：老挝万荣一对情侣失踪，失踪者是张志新（化名）和其女友刘颖，没想到半个月后，有当地人在树林里发现了一具尸体，经...
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护林员之死
正文独居荒郊野岭守林人离奇死亡，尸身上长有42处带血的脓包…… 初始之章·张勋以下内容为张勋视角年9月15日...
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白月光启示录
正文我和宋清朗相恋三年，在试婚纱的时候发现自己被绿了。大学时的朋友给我发了我未婚夫和他白月光在一起吃饭的照片。...
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活死人
序言：一个原本活蹦乱跳的男人离奇死亡，死状恐怖，灵堂内的尸体忽然破棺而出，到底是诈尸还是另有隐情，我是刑警宁泽，带...
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日本核电站爆炸内幕
正文年R本政府宣布，位于F岛的核电站，受9级特大地震影响，放射性物质发生泄漏。R本人自食恶果不足惜，却给世界环境...
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男人毒药：我在死后第九天来索命
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一桩弑父案，背后竟有这般阴谋
文/苍兰香墨我抬头看了看天上的太阳。三九已至，却和暖如春，着一层夹袄步出监牢的瞬间，已是汗流浃背。一阵脚步声响...
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情欲美人皮
我被黑心中介骗来泰国打工，没想到刚下飞机就差点儿被人妖公主榨干…… 1. 我叫王不留，地道东北人。一个月前我还...
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代替公主和亲
正文我出身青楼，却偏偏与公主长得像，于是被迫代替她去往敌国和亲。传闻我的和亲对象是个残疾皇子，可洞房花烛夜当晚...
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