Increase code readability

Recordings-MVC/Recordings/FolderViewController.swift

@@ -21,7 +21,7 @@ class FolderViewController: UITableViewController {
 		NotificationCenter.default.addObserver(self, selector: #selector(handleChangeNotification(_:)), name: Store.changedNotification, object: nil)
 	}
 
-	@objc func handleChangeNotification(_ notification: Notification) {
+	@objc private func handleChangeNotification(_ notification: Notification) {
 		// Handle changes to the current folder
 		if let item = notification.object as? Folder, item === folder {
 			let reason = notification.userInfo?[Item.changeReasonKey] as? String
@@ -56,7 +56,7 @@ class FolderViewController: UITableViewController {
 		}
 	}
 
-	var selectedItem: Item? {
+	private var selectedItem: Item? {
 		if let indexPath = tableView.indexPathForSelectedRow {
 			return folder.contents[indexPath.row]
 		}

Recordings-MVC/Recordings/PlayViewController.swift

@@ -1,16 +1,16 @@
 import UIKit
 import AVFoundation
 
-class PlayViewController: UIViewController, UITextFieldDelegate, AVAudioPlayerDelegate {
-	@IBOutlet var nameTextField: UITextField!
-	@IBOutlet var playButton: UIButton!
-	@IBOutlet var progressLabel: UILabel!
-	@IBOutlet var durationLabel: UILabel!
-	@IBOutlet var progressSlider: UISlider!
-	@IBOutlet var noRecordingLabel: UILabel!
-	@IBOutlet var activeItemElements: UIView!
+class PlayViewController: UIViewController {
+	@IBOutlet private var nameTextField: UITextField!
+	@IBOutlet private var playButton: UIButton!
+	@IBOutlet private var progressLabel: UILabel!
+	@IBOutlet private var durationLabel: UILabel!
+	@IBOutlet private var progressSlider: UISlider!
+	@IBOutlet private var noRecordingLabel: UILabel!
+	@IBOutlet private var activeItemElements: UIView!
 
-	var audioPlayer: Player?
+	private var audioPlayer: Player?
 	var recording: Recording? {
 		didSet {
 			updateForChangedRecording()
@@ -27,12 +27,12 @@ class PlayViewController: UIViewController, UITextFieldDelegate, AVAudioPlayerDe
 		NotificationCenter.default.addObserver(self, selector: #selector(storeChanged(notification:)), name: Store.changedNotification, object: nil)
 	}
 
-	@objc func storeChanged(notification: Notification) {
+	@objc private func storeChanged(notification: Notification) {
 		guard let item = notification.object as? Item, item === recording else { return }
 		updateForChangedRecording()
 	}
 
-	func updateForChangedRecording() {
+	private func updateForChangedRecording() {
 		if let r = recording, let url = r.fileURL {
 			audioPlayer = Player(url: url) { [weak self] time in
 				if let t = time {
@@ -60,15 +60,15 @@ class PlayViewController: UIViewController, UITextFieldDelegate, AVAudioPlayerDe
 		}
 	}
 
-	func updateProgressDisplays(progress: TimeInterval, duration: TimeInterval) {
+	private func updateProgressDisplays(progress: TimeInterval, duration: TimeInterval) {
 		progressLabel?.text = timeString(progress)
 		durationLabel?.text = timeString(duration)
 		progressSlider?.maximumValue = Float(duration)
 		progressSlider?.value = Float(progress)
 		updatePlayButton()
 	}
 
-	func updatePlayButton() {
+	private func updatePlayButton() {
 		if audioPlayer?.isPlaying == true {
 			playButton?.setTitle(.pause, for: .normal)
 		} else if audioPlayer?.isPaused == true {
@@ -78,24 +78,12 @@ class PlayViewController: UIViewController, UITextFieldDelegate, AVAudioPlayerDe
 		}
 	}
 
-	func textFieldDidEndEditing(_ textField: UITextField) {
-		if let r = recording, let text = textField.text {
-			r.setName(text)
-			title = r.name
-		}
-	}
-
-	func textFieldShouldReturn(_ textField: UITextField) -> Bool {
-		textField.resignFirstResponder()
-		return true
-	}
-
-	@IBAction func setProgress() {
+	@IBAction private func setProgress() {
 		guard let s = progressSlider else { return }
 		audioPlayer?.setProgress(TimeInterval(s.value))
 	}
 
-	@IBAction func play() {
+	@IBAction private func play() {
 		audioPlayer?.togglePlay()
 		updatePlayButton()
 	}
@@ -118,6 +106,27 @@ class PlayViewController: UIViewController, UITextFieldDelegate, AVAudioPlayerDe
 			self.recording = recording
 		}
 	}
+
+	deinit {
+		NotificationCenter.default.removeObserver(self)
+	}
+
+}
+
+extension PlayViewController: UITextFieldDelegate {
+
+	func textFieldDidEndEditing(_ textField: UITextField) {
+		if let r = recording, let text = textField.text {
+			r.setName(text)
+			title = r.name
+		}
+	}
+
+	func textFieldShouldReturn(_ textField: UITextField) -> Bool {
+		textField.resignFirstResponder()
+		return true
+	}
+
 }
 
 fileprivate extension String {

Recordings-MVC/Recordings/Player.swift

@@ -1,10 +1,10 @@
 import Foundation
 import AVFoundation
 
-class Player: NSObject, AVAudioPlayerDelegate {
-	private var audioPlayer: AVAudioPlayer
+class Player: NSObject {
+	private let audioPlayer: AVAudioPlayer
 	private var timer: Timer?
-	private var update: (TimeInterval?) -> ()
+	private let update: (TimeInterval?) -> ()
 
 	init?(url: URL, update: @escaping (TimeInterval?) -> ()) {
 		do {
@@ -46,12 +46,6 @@ class Player: NSObject, AVAudioPlayerDelegate {
 	func setProgress(_ time: TimeInterval) {
 		audioPlayer.currentTime = time
 	}
-
-	func audioPlayerDidFinishPlaying(_ pl: AVAudioPlayer, successfully flag: Bool) {
-		timer?.invalidate()
-		timer = nil
-		update(flag ? audioPlayer.currentTime : nil)
-	}
 
 	var duration: TimeInterval {
 		return audioPlayer.duration
@@ -69,3 +63,13 @@ class Player: NSObject, AVAudioPlayerDelegate {
 		timer?.invalidate()
 	}
 }
+
+extension Player: AVAudioPlayerDelegate {
+
+	func audioPlayerDidFinishPlaying(_ pl: AVAudioPlayer, successfully flag: Bool) {
+		timer?.invalidate()
+		timer = nil
+		update(flag ? audioPlayer.currentTime : nil)
+	}
+
+}

Recordings-MVC/Recordings/RecordViewController.swift

@@ -1,13 +1,12 @@
 import UIKit
-import AVFoundation
 
-final class RecordViewController: UIViewController, AVAudioRecorderDelegate {
-	@IBOutlet var timeLabel: UILabel!
-	@IBOutlet var stopButton: UIButton!
+final class RecordViewController: UIViewController {
+	@IBOutlet private var timeLabel: UILabel!
+	@IBOutlet private var stopButton: UIButton!
 
-	var audioRecorder: Recorder?
+	private var audioRecorder: Recorder?
 	var folder: Folder? = nil
-	var recording = Recording(name: "", uuid: UUID())
+	private let recording = Recording(name: "", uuid: UUID())
 
 	override func viewDidLoad() {
 		super.viewDidLoad()
@@ -17,7 +16,7 @@ final class RecordViewController: UIViewController, AVAudioRecorderDelegate {
 	override func viewDidAppear(_ animated: Bool) {
 		super.viewWillAppear(animated)
 
-		audioRecorder = folder?.store?.fileURL(for: recording).flatMap { url in
+		audioRecorder = folder?.store?.fileURL(for: recording).flatMap { [unowned self] url in
 			Recorder(url: url) { time in
 				if let t = time {
 					self.timeLabel.text = timeString(t)
@@ -31,7 +30,7 @@ final class RecordViewController: UIViewController, AVAudioRecorderDelegate {
 		}
 	}
 
-	@IBAction func stop(_ sender: Any) {
+	@IBAction private func stop(_ sender: Any) {
 		audioRecorder?.stop()
 		modalTextAlert(title: .saveRecording, accept: .save, placeholder: .nameForRecording) { string in
 			if let title = string {

Recordings-MVC/Recordings/Recorder.swift

@@ -1,11 +1,11 @@
 import Foundation
 import AVFoundation
 
-final class Recorder: NSObject, AVAudioRecorderDelegate {
+final class Recorder: NSObject {
 	private var audioRecorder: AVAudioRecorder?
 	private var timer: Timer?
-	private var update: (TimeInterval?) -> ()
-	let url: URL
+	private let update: (TimeInterval?) -> ()
+	private let url: URL
 
 	init?(url: URL, update: @escaping (TimeInterval?) -> ()) {
 		self.update = update
@@ -50,12 +50,17 @@ final class Recorder: NSObject, AVAudioRecorderDelegate {
 		audioRecorder?.stop()
 		timer?.invalidate()
 	}
-
+
+}
+
+extension Recorder: AVAudioRecorderDelegate {
+
 	func audioRecorderDidFinishRecording(_ recorder: AVAudioRecorder, successfully flag: Bool) {
 		if flag {
 			stop()
 		} else {
 			update(nil)
 		}
 	}
+
 }

Recordings-MVC/Recordings/Store.swift

@@ -5,7 +5,7 @@ final class Store {
 	static private let documentDirectory = try! FileManager.default.url(for: .libraryDirectory, in: .userDomainMask, appropriateFor: nil, create: true)
 	static let shared = Store(url: documentDirectory)
 
-	let baseURL: URL?
+	private let baseURL: URL?
 	var placeholder: URL?
 	private(set) var rootFolder: Folder
 

Recordings-MVC/Recordings/Utilities.swift

@@ -20,7 +20,7 @@ extension UIViewController {
 		alert.addAction(UIAlertAction(title: cancel, style: .cancel) { _ in
 			callback(nil)
 		})
-		alert.addAction(UIAlertAction(title: accept, style: .default) { _ in
+		alert.addAction(UIAlertAction(title: accept, style: .default) { [unowned alert] _ in
 			callback(alert.textFields?.first?.text)
 		})
 		present(alert, animated: true)