iOS Audio Recording

I added the recording functionality to the recordAudio action inside the viewController. I am able to easily do this using AVFoundation. AVFoundation is a framework specific for handling audiovisual media in iOS apps. As a developer, I can use AVFoundations built in classes, and the class methods to record, save and play audio recordings for my app.

import AVFoundation

class ViewController: UIViewController {

    // MARK: Properties

    var audioRecorder: AVAudioRecorder!

    @IBAction func recordAudio(_ sender: AnyObject) {
        recordingLabel.text = "Recording in progress"
        stopRecordingButton.isEnabled = true
        recordButton.isEnabled = false

        let dirPath = NSSearchPathForDirectoriesInDomains(.documentDirectory,.userDomainMask, true)[0] as String
        let recordingName = "recordedVoice.wav"
        let pathArray = [dirPath, recordingName]
        let filePath = URL(string: pathArray.joined(separator: "/"))

        let session = AVAudioSession.sharedInstance()
        try! session.setCategory(AVAudioSessionCategoryPlayAndRecord, with:AVAudioSessionCategoryOptions.defaultToSpeaker)

        try! audioRecorder = AVAudioRecorder(url: filePath!, settings: [:])        
        audioRecorder.isMeteringEnabled = true
        audioRecorder.prepareToRecord()
        audioRecorder.record()
    }
}

AVFoundation Concepts

NSSearchPathForDirectoriesInDomains`

creates a directory of search paths that the application can use to create the filePath. the Filepath is a parameter used to instantiate the AVAudioRecorder class

AVAudioRecorder

is a class that allows an application to use an iOS audio device. When the user clicks the record audio button, our action will provide the filepath location and the settings as parameters when instantiating the AVAudioRecorder class. Once instantiated, we then call its functions isMeteringEnabled(), preparedToRecord(), and record() to enable the recording functionality