當我已經從外部存儲重新選擇音頻時，在 Kotlin 中更改聲音警報時出現問題

Question

我想嘗試在 Kotlin 中進行鬧鍾 Android 應用程序實驗，以便它可以更改來自外部存儲的音頻聲音，假設我已經為來自外部存儲的鬧鍾聲音設置了“A”音頻聲音。 然后，我想通過重新選擇它來將設置為“B”音頻聲音的音頻輸入聲音更改為來自外部存儲器的警報聲音。 問題是，當我已經通過重新選擇將警報聲音的音頻輸入從音頻“A”更改為音頻“B”時，音頻“A”（上一個音頻）仍在播放警報聲音而不是音頻“B”。

所以這是 select 音頻按鈕：（忽略 requestPermission()，假設已授予權限）

binding.selectAudio.setOnClickListener()
{
    if (checkPermission())
    {
        openAudio()
    }
    else
    {
        requestPermission()
    }
}

這是當應用程序重定向到選擇音頻聲音並獲取其路徑時：

private fun openAudio()
{
    //soundPath = null
    onStop()
    val openFileIntent = Intent(Intent.ACTION_GET_CONTENT)
    openFileIntent.type = "audio/*"

    getResult.launch(openFileIntent)
}

private val getResult =
registerForActivityResult(ActivityResultContracts.StartActivityForResult())
{
    soundPath = null

    if (it.resultCode == RESULT_OK)
    {
        val uri: Uri? = it.data!!.data
        File(uri!!.getPath())

        val path = getRealPath(this, uri)
        soundPath = path

        if (soundPath != null)
        {
            Toast.makeText(this, "Audio file has been set", Toast.LENGTH_SHORT).show()
        }
    }
}

這是設置鬧鍾按鈕：

binding.setAlarmBtn.setOnClickListener()
{
    createNotificationChannel(soundPath)
    setAlarm()
    Log.e("notif", "soundpath" + soundPath.toString())
    Log.d("soundPath", soundPath.toString())
}

這是設置鬧鍾到一定時間的過程：

private fun setAlarm()
{
    try
    {
        alarmManager = getSystemService(ALARM_SERVICE) as AlarmManager
        val intent = Intent(this, AlarmReceiver::class.java)

        pendingIntent = PendingIntent.getBroadcast(this, 0, intent, PendingIntent.FLAG_IMMUTABLE)

        alarmManager[AlarmManager.RTC_WAKEUP, calendar.timeInMillis] = pendingIntent

        Toast.makeText(this, "Alarm set successfully", Toast.LENGTH_SHORT).show()
    }
    catch (e: Exception)
    {
        Toast.makeText(this, "Time is not been set", Toast.LENGTH_SHORT).show()
    }
}

最后，這是通過通知播放警報以及在輸入音頻聲音后獲取音頻 uri 路徑的時候：

private fun createNotificationChannel(path: String?)
{
    if(Build.VERSION.SDK_INT >= Build.VERSION_CODES.O)
    {
        val uri = getUri(path)
        val attributes = AudioAttributes.Builder().setUsage(AudioAttributes.USAGE_ALARM).build()

        val name : CharSequence = "AlarmReminderChannel"
        val description = "Channel For Alarm Manager"
        val importance = NotificationManager.IMPORTANCE_HIGH
        val channel = NotificationChannel("alarmManagerDemo", name, importance)
        channel.description = description
        channel.setSound(uri, attributes)

        Log.e("notif", "uri" + uri.toString())
        Log.e("notif", "uri from channel" + channel.sound.toString())

        val notificationManager = getSystemService(NotificationManager::class.java)
        notificationManager.createNotificationChannel(channel)
    }
}

private fun getUri(path: String?) : Uri?
{
    Log.e("notif", "path: "+path )
    if(path == null)
    {
        Log.e("notif", "null" )
        return Uri.parse(ContentResolver.SCHEME_ANDROID_RESOURCE + "://" + this.packageName + "/raw/music")
    }
    else
    {
        Log.e("notif", "tidak null" )
        return Uri.parse(path)
    }
}

此外，這是來自 BroadcastReceiver 的 onReceive 聲音：

class AlarmReceiver : BroadcastReceiver()
{
    override fun onReceive(context: Context?, intent: Intent?)
    {
        val bundle : Bundle? = intent!!.extras
        val i = Intent(context, DestinationActivity::class.java)

        intent!!.flags = Intent.FLAG_ACTIVITY_NEW_TASK or Intent.FLAG_ACTIVITY_CLEAR_TASK
        val pendingIntent = PendingIntent.getActivity(context, 0, i, PendingIntent.FLAG_IMMUTABLE)

        val builder = NotificationCompat.Builder(context!!, "alarmManagerDemo")
            .setSmallIcon(R.drawable.ic_launcher_background)
            .setContentTitle("Demo")
            .setContentText("Bla bla bla bla bla bla bla bla")
            .setAutoCancel(true)
            .setDefaults(NotificationCompat.DEFAULT_ALL)
            .setPriority(NotificationCompat.PRIORITY_HIGH)
            .setContentIntent(pendingIntent)

        val notificationManager = NotificationManagerCompat.from(context)
        notificationManager.notify(123, builder.build())

    }
}

那么，當鬧鍾正在播放新的輸入聲音而不是以前的輸入聲音時，如何解決這個問題以使鬧鍾聲音發生變化？

Answer 1

Android 不允許通過重新創建來更新通知頻道的聲音。 您應該先刪除現有頻道，然后再創建新頻道。 所以，試試看：

private fun createNotificationChannel(path: String?)
{
        ...
        ...
        val notificationManager = getSystemService(NotificationManager::class.java)
        notificationManager.deleteNotificationChannel("alarmManagerDemo")
        notificationManager.createNotificationChannel(channel)
    }
}