A notes app written in <100 lines of swift using SwiftUI

NotesApp.swift

import SwiftUI

let dateFormatter = DateFormatter()

struct NoteItem: Codable, Hashable, Identifiable {
    let id: Int
    let text: String
    var date = Date()
    var dateText: String {
        dateFormatter.dateFormat = "MMM d yyyy, h:mm a"
        return dateFormatter.string(from: date)
    }
}

struct ContentView : View {
    @State var items: [NoteItem] = {
        guard let data = UserDefaults.standard.data(forKey: "notes") else { return [] }
        if let json = try? JSONDecoder().decode([NoteItem].self, from: data) {
            return json
        }
        return []
    }()
    
    @State var taskText: String = ""
    
    @State var showAlert = false
    
    @State var itemToDelete: NoteItem?
    
    var alert: Alert {
        Alert(title: Text("Hey!"),
              message: Text("Are you sure you want to delete this item?"),
              primaryButton: .destructive(Text("Delete"), action: deleteNote),
              secondaryButton: .cancel())
    }
    
    var inputView: some View {
        HStack {
            TextField("Write a note ...", text: $taskText)
                .padding(EdgeInsets(top: 0, leading: 16, bottom: 0, trailing: 16))
                .clipped()
            Button(action: didTapAddTask, label: { Text("Add") }).padding(8)
        }
    }
    
    var body: some View {
        VStack {
            inputView
            Divider()
            List(items) { item in
                VStack(alignment: .leading) {
                    Text(item.dateText).font(.headline)
                    Text(item.text).lineLimit(nil).multilineTextAlignment(.leading)
                }
                .onLongPressGesture {
                    self.itemToDelete = item
                    self.showAlert = true
                }
            }
            .alert(isPresented: $showAlert, content: {
                alert
            })
        }
    }
    
    func didTapAddTask() {
        let id = items.reduce(0) { max($0, $1.id) } + 1
        items.insert(NoteItem(id: id, text: taskText), at: 0)
        taskText = ""
        save()
    }
    
    func deleteNote() {
        guard let itemToDelete = itemToDelete else { return }
        items = items.filter { $0 != itemToDelete }
        save()
    }
    
    func save() {
        guard let data = try? JSONEncoder().encode(items) else { return }
        UserDefaults.standard.set(data, forKey: "notes")
    }
}

Here is the Code without errors:

import SwiftUI

let dateFormatter = DateFormatter()

struct NoteItem: Codable, Hashable, Identifiable {
    let id: Int
    let text: String
    var date = Date()
    var dateText: String {
        dateFormatter.dateFormat = "MMM d yyyy, h:mm a"
        return dateFormatter.string(from: date)
    }
}

struct ContentView : View {
    @State var items: [NoteItem] = {
        guard let data = UserDefaults.standard.data(forKey: "notes") else { return [] }
        if let json = try? JSONDecoder().decode([NoteItem].self, from: data) {
            return json
        }
        return []
    }()
    
    @State var taskText: String = ""
    
    @State var showAlert = false
    
    @State var itemToDelete: NoteItem?
    
    var alert: Alert {
        Alert(title: Text("Hey!"),
              message: Text("Are you sure you want to delete this item?"),
              primaryButton: .destructive(Text("Delete"), action: deleteNote),
              secondaryButton: .cancel())
    }
    
    var inputView: some View {
        HStack {
            TextField("Write a note ...", text: $taskText)
                .padding(EdgeInsets(top: 0, leading: 16, bottom: 0, trailing: 16))
                .clipped()
            Button(action: didTapAddTask, label: { Text("Add") }).padding(8)
        }
    }
    
    var body: some View {
        VStack {
            inputView
            Divider()
            List(items) { item in
                VStack(alignment: .leading) {
                    Text(item.dateText).font(.headline)
                    Text(item.text).lineLimit(nil).multilineTextAlignment(.leading)
                }
                .onLongPressGesture {
                    self.itemToDelete = item
                    self.showAlert = true
                }
            }
            .alert(isPresented: $showAlert, content: {
                alert
            })
        }
    }
    
    func didTapAddTask() {
        let id = items.reduce(0) { max($0, $1.id) } + 1
        items.insert(NoteItem(id: id, text: taskText), at: 0)
        taskText = ""
        save()
    }
    
    func deleteNote() {
        guard let itemToDelete = itemToDelete else { return }
        items = items.filter { $0 != itemToDelete }
        save()
    }
    
    func save() {
        guard let data = try? JSONEncoder().encode(items) else { return }
        UserDefaults.standard.set(data, forKey: "notes")
    }
}

@SammyDerksen for some reason playgrounds gives me an abort error anyway to fix that?

This is incredible!

It helped me to improve myself in SwiftUI at the beginning. If you want to view my project: https://github.com/leparutill/Noteman/tree/main