Combine audioFiles iOS

Solution:

 You can combine audio files in swift also.You can pass the audiofile paths to one function it can combine those files and save it as single file.

Code: 

    func combineAudioFiles(audioFileUrls: NSArray,place:MyLocations,isOnEntry:Bool) {
        let composition = AVMutableComposition()

        for i in 0 ..< audioFileUrls.count {

            let compositionAudioTrack :AVMutableCompositionTrack = composition.addMutableTrack(withMediaType: AVMediaTypeAudio, preferredTrackID: CMPersistentTrackID())
            let documentsDirectory = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
            let urls = documentsDirectory.appendingPathComponent(audioFileUrls[i] as! String)
            let asset = AVURLAsset(url: urls)
            let track = asset.tracks(withMediaType: AVMediaTypeAudio).first
            let timeRange = CMTimeRange(start: CMTimeMake(0, 600), duration: (track?.timeRange.duration)!)       
            try! compositionAudioTrack.insertTimeRange(timeRange, of: track!, at: composition.duration)
        } 
        let fileManager = FileManager.default

        let documentDirectoryURL = FileManager.default.urls(for: .libraryDirectory, in: .userDomainMask).first! as NSURL
        var newUrl:NSURL!
        let newDir = documentDirectoryURL.appendingPathComponent("Sounds")?.path
       
        do{
            try fileManager.createDirectory(atPath: newDir!,withIntermediateDirectories: true, attributes: nil)
            newUrl = documentDirectoryURL.appendingPathComponent("Sounds") as! NSURL
        } catch {
            print("Error: \(error.localizedDescription)")
        }
        let mergeAudioFiles = isOnEntry == true ? newUrl!.appendingPathComponent("\(place.locationID)entry.m4a") as! URL as NSURL : newUrl!.appendingPathComponent("combinedAudio.m4a") as! URL as NSURL
        if fileManager.fileExists(atPath: mergeAudioFiles.path!) {
            do{
                try fileManager.removeItem(atPath: mergeAudioFiles.path!)
            } catch {
                //Do nothing
            }
        }

        let assetExport = AVAssetExportSession(asset: composition, presetName: AVAssetExportPresetAppleM4A)
        assetExport?.outputFileType = AVFileTypeAppleM4A
        assetExport?.outputURL = mergeAudioFiles as URL
        assetExport?.exportAsynchronously(completionHandler:
            {
                switch assetExport!.status
                {
                case AVAssetExportSessionStatus.failed:
                    print("failed \(assetExport?.error)")
                case AVAssetExportSessionStatus.cancelled:
                    print("cancelled \(assetExport?.error)")
                case AVAssetExportSessionStatus.unknown:
                    print("unknown\(assetExport?.error)")
                case AVAssetExportSessionStatus.waiting:
                    print("waiting\(assetExport?.error)")
                case AVAssetExportSessionStatus.exporting:
                    print("exporting\(assetExport?.error)")
                default:
                  
                    print("Audio Concatenation Complete")
                }
        })
    
       
       
    }