I have a tabbed app that starts recording on one tab, and plots the mic levels on another tab.
In the first VC, I'm gathering mic levels and storing them in an array in the model. I'm using another method in the model to update the data, and I'm calling it in the second VC in order to update the view.
What I want to do is update the chart in the second view controller from the first view controller (where the logic for storing data in the model is)
Model:
Chart.swift
import Charts
class Chart {
static let sharedInstance = Chart()
var lineChartView: LineChartView!
func setChartValues() {
let entries = (0..<GraphData.sharedInstance.array.count).map { (i) -> ChartDataEntry in
let val = GraphData.sharedInstance.array[i]
print(ChartDataEntry(x: Double(i), y: val))
return ChartDataEntry(x: Double(i), y: val)
}
let set1 = LineChartDataSet(values: entries, label: "DataSet 1")
let data = LineChartData(dataSet: set1)
lineChartView.data = data
}
}
GraphData.swift
class GraphData {
static let sharedInstance = GraphData()
var array = [Double]()
}
View Controllers:
First VC: (complete code per comment)
import UIKit import AVFoundation
class SoundController: UIViewController, AVAudioRecorderDelegate {
var recordingSession: AVAudioSession!
var audioRecorder: AVAudioRecorder!
var timer = Timer()
@IBOutlet weak var errorLbl: UILabel!
@IBOutlet weak var recordBtn: UIButton!
@IBAction func recordButton(_ sender: UIButton) {
if audioRecorder == nil {
startRecording()
} else {
finishRecording(success: true)
}
}
override func viewWillAppear(_ animated: Bool) {
super.viewWillAppear(false)
errorLbl.text = ""
}
override func viewDidLoad() {
super.viewDidLoad()
recordPermission()
}
func recordPermission() {
recordingSession = AVAudioSession.sharedInstance()
do {
try recordingSession.setCategory(.playAndRecord, mode: .default)
try recordingSession.setActive(true)
recordingSession.requestRecordPermission() { allowed in
DispatchQueue.main.async {
if allowed {
print("recording allowed")
} else {
self.errorLbl.text = "Recording Permission was Denied. Please open settings and allow Cry It Out to access the microphone."
}
}
}
} catch {
self.errorLbl.text = "Recording Permission was Denied. Please open settings and allow the app to access the microphone."
}
}
func getDocumentsDirectory() -> URL {
let paths = FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)
return paths[0]
}
func startRecording() {
if recordBtn.titleLabel?.text == "Tap to Re-record" {
//reset values array
GraphData.sharedInstance.array = []
}
let audioFilename = getDocumentsDirectory().appendingPathComponent("baby.m4a")
let settings = [
AVFormatIDKey: Int(kAudioFormatMPEG4AAC),
AVSampleRateKey: 12000,
AVNumberOfChannelsKey: 1,
AVEncoderAudioQualityKey: AVAudioQuality.high.rawValue
]
do {
audioRecorder = try AVAudioRecorder(url: audioFilename, settings: settings)
audioRecorder.delegate = self
audioRecorder.isMeteringEnabled = true
runTimer()
audioRecorder.record()
runTimer()
recordBtn.setTitle("Tap to Stop", for: .normal)
} catch {
finishRecording(success: false)
}
}
func levelTimerCallback() -> Float {
if audioRecorder != nil {
audioRecorder.updateMeters()
//If we are beyond a threshold value (-15)
if audioRecorder.averagePower(forChannel: 0) > -15 {
return audioRecorder.averagePower(forChannel: 0)
}
}
return 0
}
func finishRecording(success: Bool) {
//stop recording and reset recorder to nil for other checks
audioRecorder.stop()
audioRecorder = nil
if success {
recordBtn.setTitle("Tap to Re-record", for: .normal)
if timer.isValid {
timer.invalidate()
}
} else {
//Recording Failed
recordBtn.setTitle("Tap to Record", for: .normal)
//disable timer if running (might be running or might not)
if timer.isValid {
timer.invalidate()
}
}
}
func audioRecorderDidFinishRecording(_ recorder: AVAudioRecorder, successfully flag: Bool) {
if !flag {
finishRecording(success: false)
}
}
//MARK: Timers
@objc func updateTimer() {
if levelTimerCallback() != 0 {
let date = Date()
let calendar = Calendar.current
let month = calendar.component(.month, from: date)
let day = calendar.component(.day, from: date)
let hour = calendar.component(.hour, from: date)
let minutes = calendar.component(.minute, from: date)
let seconds = calendar.component(.second, from: date)
let prettyDate = "\(month)/\(day) \(hour):\(minutes) and \(seconds) seconds"
print(prettyDate)
GraphData.sharedInstance.array.append(Double(levelTimerCallback()))
//does this run the method? It should
GraphController.sharedInstance.lineChartView?.data = Chart.sharedInstance.setChartValues()
}
}
func runTimer() {
timer = Timer.scheduledTimer(timeInterval: 1, target: self, selector: (#selector(SoundController.updateTimer)), userInfo: nil, repeats: true)
}
func stopTimer() {
timer.invalidate()
}
}
Second VC:
import UIKit
import Charts
class GraphController: UIViewController {
static let sharedInstance = GraphController()
@IBOutlet weak var lineChartView: LineChartView!
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(true)
self.lineChartView.data = Chart.sharedInstance.setChartValues()
}
}
