hmlongco

@MainActor
class Test {
    // can do this
    func someTask1() {
        let _ = ""
        Task {
            let _ = ""
            let data = await doBackgroundTask()
            let _ = data // Update UI with data
        }

hmlongco

class MyViewModel: ObservableObject {
    @Published var items: [Item] = []

    @MainActor
    func loadData() async {
        items = await fetchData()
    }
}

struct MyView: View {

hmlongco

// original code, intermediate variable
class SomeViewModel1: ObservableObject {
    @Published var searchResults: [String] = []
    private var currentSearchTask: Task<Void, Never>?
    @MainActor
    func search(_ query: String) {
        currentSearchTask?.cancel()
        let newTask = Task {
            do {
                try await Task.sleep(for: .milliseconds(500))

hmlongco

// instead of "nested" try catches...

public func load() async throws -> [FeedItem] {
    do {
        let (data, response) = try await client.get(from: url)
        guard let httpResponse = response as? HTTPURLResponse else {
            throw Error.invalidData
        }
        
        guard httpResponse.statusCode == 200 else {

hmlongco

struct User {
    var firstName: String
    var lastName: String
    var email: String
    var phoneNumber: String
    var street: String
    var city: String
    var state: String
    var zipCode: String
}

hmlongco

struct Account: Identifiable {
    let id = UUID().uuidString
}

struct SheetLaunchingDemoView: View {
    @State var showSheet: Account?
    var body: some View {
        NavigationStack {
            Button("Show Sheet") {
                showSheet = Account()

hmlongco

class InterruptedTaskViewModel: ObservableObject {
    @Published var name = "Michael"
    init() {
        print("INIT")
    }
    @MainActor
    func load() {
        Task {
            print("LOADING")
            let _ = try? await Task.sleep(nanoseconds: 3 * NSEC_PER_SEC)

hmlongco

struct ChildStateDemo: View {
    @State var account = 1
    var body: some View {
        VStack(spacing: 20) {
            SubView(id: account)
                .id(account) // required to change subview state
          
            Button("Account 1") {
                account = 1
            }

hmlongco

struct ParentView: View {
    @State var id = UUID().uuidString
    var body: some View {
        VStack(spacing: 20) {
            VStack {
                Text("Parent View")
                Text(id).font(.footnote)
            }
            ChildView(name: "Child Maintains State On Update")
            ChildView(name: "Child Loses State On Update")

hmlongco

import SwiftUI

class ContentModel: ObservableObject {
    @Published var count: Int = 0
    let items10 = (0 ..< 10).map { Item(id: $0 + 1) }
    let items100 = (0 ..< 100).map { Item(id: $0 + 1) }
    let items10K = (0 ..< 10_000).map { Item(id: $0 + 1) }
    let items100K = (0 ..< 100_000).map { Item(id: $0 + 1) }
}