I can't dynamically add items to List. SwiftUI

Question

I can't dynamically add items to List. SwiftUI. I'm new at SwiftUI, so i don't know why it's not working

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import SwiftUI

struct UpdateList : View {
    var updates = updateData
    @ObservedObject var store = UpdateStore(updates: updateData)
**Update func doesn't work(It doesn't add anything)**
    func addUpdate() {
        store.updates.append(Update(image: "Certificate1", title: "New Title", text: "New Text", date: "JUL 1"))
    }
    
    func move(from source: IndexSet, to destination: Int) {
        store.updates.swapAt(source.first!, destination)
    }
    
    var body: some View {
        NavigationView {
**List Code**
            List {
                ForEach(store.updates) { item in
                    NavigationLink(destination: UpdateDetail(title: item.title, image: item.image, text: item.text)) {
                        HStack(spacing: 12.0) {
                            Image(item.image)
                                .resizable()
                                .aspectRatio(contentMode: .fit)
                                .frame(width: 80, height: 80)
                                .background(Color("background"))
                                .cornerRadius(20)
                            
                            VStack(alignment: .leading) {
                                Text(item.title)
                                    .font(.headline)
                                Text(item.text)
                                    .lineLimit(2)
                                    .lineSpacing(4)
                                    .font(.subheadline)
                                    .frame(height: 40.0)
                                Text(item.date)
                                    .font(.caption)
                                    .fontWeight(.bold)
                                    .foregroundColor(Color.gray)
                            }
                        }
                    }
                    .padding(.vertical, 8.0)
                }
                .onDelete { index in
                    self.store.updates.remove(at: index.first!)
                }
                .onMove(perform: move)
                
            }
            .navigationBarTitle(Text("Updates"))
            .toolbar{
                ToolbarItem{
                    HStack {
                        Button(action: addUpdate) {
                            Text("Add Update")
                                .foregroundColor(Color.white)
                        }
                        .padding(8)
                        .background(Color("background3"))
                        .cornerRadius(8)
                        EditButton()
                    }
                }
            }
        }
        
    }
}

struct UpdateList_Previews : PreviewProvider {
    static var previews: some View {
        UpdateList()
    }
}

struct Update: Identifiable {
    var id = UUID()
    var image: String
    var title: String
    var text: String
    var date: String
}

var updateData = [
    Update(image: "Illustration1", title: "SwiftUI", text: "Learn how to build custom views and controls in SwiftUI with advanced composition, layout, graphics, and animation. See a demo of a high performance, animatable control and watch it made step by step in code. Gain a deeper understanding of the layout system of SwiftUI.", date: "JUN 26")
    



UpdateStore file
import SwiftUI
import Combine

class UpdateStore : ObservableObject {
    var didChange = PassthroughSubject<Void, Never>()
    var updates: [Update] {
        didSet{
            didChange.send()
        }
    }
    
    init(updates: [Update] = []) {
        self.updates = updates
    }
}

I'm expecting add a new list item everytime I tap the button("Add Update")

Answer 1

Seems to work fine for me. Do you have @Published set on your Update? Also some minor tweaks in the view initialisation. You can not pass a view variable in to the class on init.

class UpdateStore: ObservableObject {

@Published var updates: [Update] = []

}

struct UpdateList : View {
var updates = updateData
@ObservedObject var store = UpdateStore()
//**Update func that doesn't work(It doesn't add anything**
func addUpdate() {
    store.updates.append(Update(image: "Certificate1", title: "New Title", text: "New Text", date: "JUL 1"))
}

func move(from source: IndexSet, to destination: Int) {
    store.updates.swapAt(source.first!, destination)
}

var body: some View {
    NavigationView {
//**List Code**
        List {
            ForEach(store.updates) { item in
                NavigationLink(destination: EmptyView()) {
                    HStack(spacing: 12.0) {
                        Image(item.image)
                            .resizable()
                            .aspectRatio(contentMode: .fit)
                            .frame(width: 80, height: 80)
                            .background(Color("background"))
                            .cornerRadius(20)
                        
                        VStack(alignment: .leading) {
                            Text(item.title)
                                .font(.headline)
                            Text(item.text)
                                .lineLimit(2)
                                .lineSpacing(4)
                                .font(.subheadline)
                                .frame(height: 40.0)
                            Text(item.date)
                                .font(.caption)
                                .fontWeight(.bold)
                                .foregroundColor(Color.gray)
                        }
                    }
                }
                .padding(.vertical, 8.0)
            }
            .onDelete { index in
                self.store.updates.remove(at: index.first!)
            }
            .onMove(perform: move)
            
        }
        .navigationBarTitle(Text("Updates"))
        .toolbar{
            ToolbarItem{
                HStack {
                    Button(action: addUpdate) {
                        Text("Add Update")
                            .foregroundColor(Color.blue)
                    }
                    .padding(8)
                    .background(Color("background3"))
                    .cornerRadius(8)
                    EditButton()
                }
            }
        }
    }
    
}
}