Core Data - Data Transfer SwiftUI

Question

I am trying to transfer CDListModel to my Today View but I can not do it properly. So that I can see how many reminders I have totally today in list.reminders.count. Right now I am getting 0

    struct Today: View {
    @Environment(\.managedObjectContext) private var viewContext
    @ObservedObject var list: CDListModel
    @State var isTodayTapped = false
    var body: some View {
        Button(action: {
            self.isTodayTapped.toggle()
        }) {
            ZStack{
                RoundedRectangle(cornerRadius: 15)
                    .foregroundColor(.white)
                HStack(alignment: .top, spacing: 100) {
                    Text(String(list.reminders!.count))
                }
            }
        }
        .fullScreenCover(isPresented: $isTodayTapped) {
            TodayView()
        }
    }
}

MainPageView

    struct MainPageView: View {
    @Environment(\.managedObjectContext) private var viewContext
    var list: CDListModel
    var body: some View {
        ZStack {
            NavigationView {
                ZStack {
                    VStack{
                        HStack(spacing: 20){
                            Today(list: list) //What should I send here?
                                .environment(\.managedObjectContext, viewContext)
                        }
                    }
                }
            }
        }
    }
}

ContentView

 struct ContentView: View {
    @Environment(\.managedObjectContext) private var viewContext

    @State var selectedList = ListModel(color: "", text: "", reminders: [])
   
    var body: some View {
         MainPageView(selectedList: $selectedList, list: CDListModel())
            .environment(\.managedObjectContext, viewContext)
    }
}

Your question is not clear. What is CDListModel? Your code doesn't show anything about CoreData. You aren't observing, fetching, etc. — lorem ipsum

Mert Köksal Mert Köksal · Accepted Answer · 2021-05-07T12:08:17

You do not need to transfer data from another view to Today view. Because the data you need is already inside the core data so you can reach to data using

@FetchRequest( entity: CDReminder.entity(),
                   sortDescriptors:
                    [NSSortDescriptor(keyPath: \CDReminder.date, ascending: true)]
    )var reminder: FetchedResults<CDReminder>

inside the Today view without modifying any of the other views.

Change Today as below

struct Today: View {
    @Environment(\.managedObjectContext) private var viewContext
    @FetchRequest( entity: CDReminder.entity(),
                   sortDescriptors:
                    [NSSortDescriptor(keyPath: \CDReminder.date, ascending: true)]
    )var reminder: FetchedResults<CDReminder>

    @State var isTodayTapped = false
    var body: some View {
        Button(action: {
            self.isTodayTapped.toggle()
        }) {
            ZStack{
                RoundedRectangle(cornerRadius: 15)
                    .foregroundColor(.white)
                HStack(alignment: .top, spacing: 100) {
                    Text(String(list.reminders!.count))
                }
            }
        }
        .fullScreenCover(isPresented: $isTodayTapped) {
            TodayView()
        }
    }
}

MainPage as below

struct MainPageView: View {
    @Environment(\.managedObjectContext) private var viewContext
    var body: some View {
        ZStack {
            NavigationView {
                ZStack {
                    VStack{
                        HStack(spacing: 20){
                            Today()
                                .environment(\.managedObjectContext, viewContext)
                        }
                    }
                }
            }
        }
    }
}

ContentView as below

struct ContentView: View {
    @Environment(\.managedObjectContext) private var viewContext

    @State var selectedList = ListModel(color: "", text: "", reminders: [])
   
    var body: some View {
        MainPageView(selectedList: $selectedList)
            .environment(\.managedObjectContext, viewContext)
    }
}

Core Data - Data Transfer SwiftUI

1 Answers