Question

我需要在我的ios应用中接收推送通知时播放自定义声音。

我知道，苹果不支持静音模式下的声音警报。我尝试使用自定义声音发送推送通知。它在设备未静音时播放，并以静音模式振动。

但是，最近我找到了一个应用程序 - Chipolo，即使应用程序处于被杀死状态，也会以静音模式显示自定义声音。

用于播放声音警报的技术是什么？

非常感谢任何帮助！

Answer 1

我们无法在接收推送通知时更改系统声音，但我们可以使用MediaPlayer和AVFoundation播放音频。我们需要使用Notification Service扩展来处理前台和后台通知

在NotificationService Extension中

import UserNotifications
import AVFoundation
import MediaPlayer

class NotificationService: UNNotificationServiceExtension {


    var contentHandler: ((UNNotificationContent) -> Void)?
    var bestAttemptContent: UNMutableNotificationContent?

    override func didReceive(_ request: UNNotificationRequest, withContentHandler contentHandler: @escaping (UNNotificationContent) -> Void) {
        self.contentHandler = contentHandler
        bestAttemptContent = (request.content.mutableCopy() as? UNMutableNotificationContent)

        // Properties
        var error:NSError?
        var audioPlayer = AVAudioPlayer()

        let tempInfo = request.content.userInfo as! [String:NSObject]
        var songName = ""
        if tempInfo.index(forKey: "SoundFileName") != nil {
            songName = (tempInfo["SoundFileName"] as! String)
        }

        var opecode = ""
        if tempInfo.index(forKey: "Opcode") != nil {
            opecode = (tempInfo["Opcode"] as! String)
        }

        if opecode == "RingDevice" {
            var songTitle = ""
            var songExtension = ""
            if songName == "" {
                songTitle = "Input"
                songExtension = "caf"
            } else  {
                let testStr = songName.components(separatedBy: ".")
                songTitle = "\(testStr[0])"
                songExtension = "\(testStr[1])"
            }

                if let url = Bundle.main.url(forResource: "\(songTitle)", withExtension: "\(songExtension)")  {

                    let volumeView = MPVolumeView()
                    if let view = volumeView.subviews.first as? UISlider{
                        view.value = 1.0 //---0 t0 1.0---

                    }

                    do {
                        try AVAudioSession.sharedInstance().setCategory(AVAudioSessionCategoryPlayback)

                        try AVAudioSession.sharedInstance().setActive(true)

                        audioPlayer = try AVAudioPlayer(contentsOf: url,  fileTypeHint: AVFileType.caf.rawValue)
                        audioPlayer.volume = 1.0
                        DispatchQueue.main.asyncAfter(deadline: .now() + 5) { // Give 5 sec delay to play audio or else audio will not hearable
                             audioPlayer.play()
                        }
                    } catch _ as NSError {
                        print("[SoundPlayer] There was an error: \(String(describing: error))")
                    }

                    if (audioPlayer.isPlaying) {
                        audioPlayer.stop()
                    }
                    audioPlayer.play()
                }
        }


        if let bestAttemptContent = bestAttemptContent {
            // Modify the notification content here...            
            bestAttemptContent.title = "\(bestAttemptContent.title)"

            contentHandler(bestAttemptContent)
        }
    }

    override func serviceExtensionTimeWillExpire() {
        // Called just before the extension will be terminated by the system.
        // Use this as an opportunity to deliver your "best attempt" at modified content, otherwise the original push payload will be used.
        if let contentHandler = contentHandler, let bestAttemptContent =  bestAttemptContent {
            contentHandler(bestAttemptContent)
        }
    }

}

在我的情况下，我需要检查推送通知SoundFileName和Opcode中的两个参数。如果Opcode是RingDevice，则表示我正在播放PushNotification中提到的声音

别忘了启用后台模式

希望这会对你有所帮助:)。

Answer 2

关于在设备处于静音模式时播放声音，您根本无法立即执行。只有Apple才能在出现紧急情况（例如找到设备）时覆盖静音开关。您也需要获得Apple的特殊许可，您的应用才能做到这一点。

Ganesh的答案是没有它的最佳选择。

以静音模式播放声音，app杀死状态

2 个答案: