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"Stream" data from child view to parent view

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@gs  

Hello,

I'm a Swift newbie and building an app that helps with dictation for MacOS. Here is the overview of how the project is setup.

  1. SpeechRecognizerManager (ObservableObject Class): Handles all things to do with speech recognition - Permissions, Start transcribing, Stop transcribing and has a variable transcribedText which outputs in real-time as the user is talking.
  2. ListeningButton (Swift UI): Creates a button that handles all cases of listening using SpeechRecognizerManager. Permissions (onAppear), Start & Stop transcribing (On Toggle), Button's UI changes (On Toggle). It has two binding variables: isListening & transcribedText. The goal for these variables is to always keep the parent view updated with the latest status.
  3. ContentView (Swift UI): I plan to call the ListeningButton to various views, testing with first view currently. I have access to both isListening & transcribedText. However, I only get access to transcribedText when the listening is stopped.

Requirement: Get access to transcribedText in the parent view as the text is transcribed, in real-time.

Possible Solutions: Below are the solutions I can think of as a newbie. I'd like to know if there are any other solutions or one of these are recommended.

  1. Somehow get access to SpeechRecognizerManager.transcribedText in the parent view. I don't know if it is possible and how so. (Update: I figured out how to do this based on @dbtl88's correction of GPT-4 coding skills :) I still need to know if this is the best way or not.)
  2. Change the ListeningButton UI to constantly (using while isListening: true) set transcribedText = SpeechRecognizerManager.transcribedText. Is this recommended? Feels like a "hack", but I'm not sure.
  3. Make the Real-time streaming of transcribedText as part of the ListeningButton UI. I don't really prefer this as it limits the UI functionality in the Parent Views.
  4. Any other better way?

ListeningButton:

import SwiftUI

struct ListeningButton: View {
    @StateObject var speechRecognizerManager: SpeechRecognizerManager = SpeechRecognizerManager()

    // State variable to track hover status
    @State private var isHovering : Bool = false
    @State private var blink : Bool = false

    @Binding var isListening : Bool
    @Binding var transcribedText: String

    let blinkTimer = Timer.publish(every: 0.7, on: .main, in: .common).autoconnect() // Timer to trigger the blink

    var body: some View {
        Button(action: toggleListening) {
            Image(systemName: "mic")
                .imageScale(.large)
                .foregroundColor(isHovering ? .green : (colorScheme == .dark ? .black : .white)) // Adapt foreground color & change color on hover
                .opacity(blink ? 0.1 : 1.0) // Blink effect by changing opacity
                .padding()                // Add padding to increase the circular area
                .background(self.isListening ? Color.red : Color.blue) // Red when recording
                .clipShape(Circle())      // Clip the background to a circle shape
                .onHover { hovering in
                    isHovering = hovering
                }
        }
        .onReceive(blinkTimer) { _ in
            if isListening {
                withAnimation(.easeInOut(duration: 0.5)) {
                    blink.toggle()
                }
            }
        }
        .onAppear {
            requestSpeechRecognitionPermission()
            blink = false
        }
        .onDisappear {
            blinkTimer.upstream.connect().cancel() // Cancel the timer when the view disappears
        }

    }

    private func toggleListening() {
        if isListening {
            speechRecognizerManager.stopTranscribing()
            blinkTimer.upstream.connect().cancel() // Stop blinking when not listening
            blink = false
            transcribedText = speechRecognizerManager.transcribedText
        } else {
            speechRecognizerManager.startTranscribing()
            transcribedText = speechRecognizerManager.transcribedText
            blinkTimer.upstream.connect() // Start blinking when listening
        }
        isListening.toggle() // Update the listening state
    }

    private func requestSpeechRecognitionPermission() {
        speechRecognizerManager.requestSpeechAuthorization()
    }
}

Relevant code from the ContentView:

import SwiftUI

struct ContentView: View {    
    @State private var transcribedText: String = ""
    @State private var isListening : Bool = false
    var body: some View {
    ScrollView {
                    ZStack (alignment:.bottomTrailing) {
                        ListeningButton(isListening: $isListening, transcribedText: $transcribedText)
                        VStack() {
                            Text(transcribedText)
                                .padding()
                            Text(isListening ? "Listening" : "Not Listening")
                                .padding()
                        }
                    }
                }

Relevant code of SpeechRecognizerManager:

class SpeechRecognizerManager: ObservableObject {

     ... 

    @Published var transcribedText: String = ""

    ...

    if let result = result {
                    DispatchQueue.main.async {
                        self?.transcribedText = result.bestTranscription.formattedString
                    }
                    isFinal = result.isFinal
                }

Thanks!

2      

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