SwiftUI: Update ObservableObject array in Detail TabView to update Main ListView

Question

I am new to programming and SwiftUI so this will be basic. (this code is a combination of different ObservableObject tutorials I found so there are unnecessary/wrong steps, in fact, the whole thing might be wrong). Any help is greatly appreciated!!

I have a Main listview of four 'switch' rows, each with a switchTask property. The detail view is a Tabview with a few screens. When a user updates the switchTask in any detail tabviews, I need that task property to update in the main listview for the respective SwitchRow.

My ObservableObject is an array switches. I am having trouble figuring out how to correctly pass each Switch instance to the Tabview details (PluggedInDetail) so the corresponding switchTask in main listview is updated. Should I be using EnvironmentObject instead?

ObservableObject and Row:

import SwiftUI
import Combine

class Switch: ObservableObject, Identifiable {

    let id = UUID()
    @Published var switchName: String
    @Published var switchTask: String

    init (switchName: String, switchTask: String) {
         self.switchName = switchName
         self.switchTask = switchTask
   }
}

class Switches: ObservableObject {

    //private init() { }
    static let shared = Switches()

    @Published var switches: [Switch]

    init() {
        //switchTask is to be updated on tabview detail
        self.switches = [
        Switch(switchName: "Switch Input 1", switchTask: ""),
        Switch(switchName: "Switch Input 2", switchTask: ""),
        Switch(switchName: "Switch Input 3", switchTask: ""),
        Switch(switchName: "Switch Input 4", switchTask: "")]
    }
}
struct SwitchRow: View {
  
    @ObservedObject var myswitch: Switch

    var body: some View {
        HStack{
            Image(systemName: "circle")
            VStack{
                Text(myswitch.switchName)
                Text(myswitch.switchTask)
           }
        }
    }
}

ContentView:

struct ContentView: View {

    @ObservedObject var myswitches: Switches = .shared

    var body: some View {
        NavigationView{
            VStack {
                List(Array(myswitches.switches.enumerated()), id: \.element.id) { (i, Switch) in
                    NavigationLink(destination: tabDetail()){
                        SwitchRow(myswitch: self.myswitches.switches[i])
                    }
                }
            }
        }
    }
}
struct tabDetail: View {

    @ObservedObject var detailSwitches: Switches = .shared

    var body: some View {
        TabView {
            PluggedInDetail()
                .tabItem {
                    Text("Plugged In")
            }

            TVDetail()
                .tabItem {
                    Text("TV")
            }
        }
    }
}

Detail View: (currently hardcoded the array element to update for Switch Input 1. This is where I need help)

import SwiftUI 
import Combine

struct PluggedInDetail: View {

    @ObservedObject var detailSwitches: Switches = .shared

    var body: some View {
        VStack {
            // switchName should display in the text
            Text(self.detailSwitches.switches[0].switchName)
            Button(action: {
                        //This should update switchTask for whichever switch element is selected
                        self.detailSwitches.switches[0].switchTask = "Direct Press"  
                    }) {
                        Text("Add Direct Press")
                   }
                }
            }
        }

score 0 · Accepted Answer · answered Dec 18 '20 at 22:32

struct SharedOO: View {
    @ObservedObject var myswitches: Switches = .shared
    
    var body: some View {
        NavigationView{
            VStack {
                List(myswitches.switches, id: \.id) { switche in
                    //You should only pass the individual item from here since the View is for a single Switch
                    NavigationLink(destination: SwitchDetail(switche: switche)){
                        SwitchRow(myswitch: switche)
                    }
                }
            }
        }
    }
}
struct SwitchDetail: View {
    @ObservedObject var switche: Switch
    
    var body: some View {
        TabView {
            PluggedInDetail().environmentObject(switche)
                .tabItem {
                    Text("Plugged In")
                }
            /*//No Code Provided
             TVDetail()
             .tabItem {
             Text("TV")
             }
             */
        }
    }
}
struct PluggedInDetail: View {
    
    @EnvironmentObject var switche: Switch
    
    var body: some View {
        VStack {
            // switchName should display in the text
            Text(self.switche.switchName)
            Text(self.switche.switchTask)
            Button(action: {
                //This should update switchTask for whichever switch element is selected
                self.switche.switchTask = "Direct Press"
            }) {
                Text("Add Direct Press")
            }
        }
    }
}
class Switch: ObservableObject, Identifiable {
    
    let id = UUID()
    @Published var switchName: String
    @Published var switchTask: String
    
    init (switchName: String, switchTask: String) {
        self.switchName = switchName
        self.switchTask = switchTask
    }
}

class Switches: ObservableObject {
    
    //private init() { }
    static let shared = Switches()
    
    @Published var switches: [Switch]
    
    init() {
        //switchTask is to be updated on tabview detail
        self.switches = [
            Switch(switchName: "Switch Input 1", switchTask: ""),
            Switch(switchName: "Switch Input 2", switchTask: ""),
            Switch(switchName: "Switch Input 3", switchTask: ""),
            Switch(switchName: "Switch Input 4", switchTask: "")]
    }
}
struct SwitchRow: View {
    
    @ObservedObject var myswitch: Switch
    
    var body: some View {
        HStack{
            Image(systemName: "circle")
            VStack{
                Text(myswitch.switchName)
                Text(myswitch.switchTask)
            }
        }
    }
}

SwiftUI: Update ObservableObject array in Detail TabView to update Main ListView

1 Answers1