SOLVED: Async Await with a For Loop

@ShadowDES

May '23

Posted below is just a test app. The premise is that I'm trying is to go through an array, each time running code that may take a second to run. I would like the function to start and finish before the next one starts. It does not return anything. With the current code, it starts the function 5 times "all at once", then finishes "at the same time". I would like the output to be "Start one", "End one", then "Start one" "End one"...

import SwiftUI

struct ContentView: View {
    var body: some View {
        VStack {
            Image(systemName: "globe")
                .imageScale(.large)
                .foregroundColor(.accentColor)
            Text("RunAll")
        }
        .onTapGesture {
            runAll()
        }
        .padding()
        .font(.largeTitle)
    }

    func runAll() {
        print("Here is the loop")
        for _ in 1...5 {
            Task {
                await one()
            }
        }
    }

    func one() async {
        print("Start one")
        delayWithSeconds(5) {
           print("End one")
        }
    }

    func delayWithSeconds(_ seconds: Double, completion: @escaping () -> ()) {
        DispatchQueue.main.asyncAfter(deadline: .now() + seconds) {
            completion()
        }
    }
}

@Bnerd

May '23

A simple approach:

struct ContentView: View {

    @State private var loadStatus: Bool =  false // We will monitor the toggling
    @State private var itemsLoaded = 0 // Follows up what is loaded

    var body: some View {
        VStack {
            Image(systemName: "globe")
                .imageScale(.large)
                .foregroundColor(.accentColor)
            Text("RunAll")
        }
        .onTapGesture {
            print("Here is the loop")
            runAll()
        }
        .onChange(of: loadStatus, perform: { _ in // Added
            if itemsLoaded <= 5 - 1 { // 5 is Your array Count
            runAll()
        }
        })
        .padding()
        .font(.largeTitle)
    }

    func runAll() { //Modified

            Task {
                await one()
            }
    }

    func one() async {
        print("Start one")
        delayWithSeconds(5) {
            itemsLoaded += 1
            loadStatus.toggle()
           print("End one")
        }
    }

    func delayWithSeconds(_ seconds: Double, completion: @escaping () -> ()) {
        DispatchQueue.main.asyncAfter(deadline: .now() + seconds) {
            completion()
        }
    }
}

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