🍎

import SwiftUI

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
        }
    }
}

struct ContentView: View {
    var body: some View {
        Text("Hello, World!")
    }
}

struct CounterView: View {
    @State private var count = 0
    
    var body: some View {
        VStack {
            Text("Count: \(count)")
            Button("Increment") {
                count += 1
            }
        }
    }
}

// Text
Text("Hello")
    .font(.title)
    .fontWeight(.bold)
    .foregroundColor(.blue)
    .lineLimit(2)

// Image
Image(systemName: "star.fill")
    .resizable()
    .aspectRatio(contentMode: .fit)
    .frame(width: 100, height: 100)

Image("photo")
    .clipShape(Circle())
    .overlay(Circle().stroke(.white, lineWidth: 2))
    .shadow(radius: 5)

// Button
Button("Tap me") {
    print("Tapped")
}
.buttonStyle(.borderedProminent)

Button(action: doSomething) {
    Label("Add", systemImage: "plus")
}

// TextField
@State private var text = ""
TextField("Placeholder", text: $text)
    .textFieldStyle(.roundedBorder)

// SecureField
SecureField("Password", text: $password)

// Toggle
@State private var isOn = false
Toggle("Enable", isOn: $isOn)

// Vertical stack
VStack(alignment: .leading, spacing: 10) {
    Text("First")
    Text("Second")
    Text("Third")
}

// Horizontal stack
HStack(spacing: 20) {
    Image(systemName: "star")
    Text("Rating")
    Spacer()
    Text("5.0")
}

// Depth stack (overlay)
ZStack {
    Color.blue
    Text("On top")
}

// List
List {
    ForEach(items) { item in
        Text(item.name)
    }
    .onDelete(perform: deleteItems)
}
.listStyle(.insetGrouped)

// LazyVGrid
let columns = [
    GridItem(.flexible()),
    GridItem(.flexible())
]

LazyVGrid(columns: columns, spacing: 20) {
    ForEach(items) { item in
        ItemView(item: item)
    }
}

// ScrollView
ScrollView {
    VStack {
        ForEach(0..<100) { i in
            Text("Row \(i)")
        }
    }
}

Text("Hello")
    .padding()
    .background(Color.blue)
    .foregroundColor(.white)
    .cornerRadius(10)
    .shadow(radius: 5)
    .frame(width: 200, height: 100)
    .opacity(0.8)
    .rotationEffect(.degrees(45))
    .scaleEffect(1.5)

Text("Hello")
    .foregroundColor(isActive ? .blue : .gray)
    .fontWeight(isImportant ? .bold : .regular)

// Custom modifier
struct CardModifier: ViewModifier {
    func body(content: Content) -> some View {
        content
            .padding()
            .background(Color.white)
            .cornerRadius(10)
            .shadow(radius: 5)
    }
}

extension View {
    func cardStyle() -> some View {
        modifier(CardModifier())
    }
}

// Usage
Text("Card").cardStyle()

// @State - local state
@State private var count = 0

// @Binding - two-way binding from parent
struct ChildView: View {
    @Binding var value: Int
}

// @StateObject - create observable object
@StateObject private var viewModel = MyViewModel()

// @ObservedObject - observe from parent
struct ChildView: View {
    @ObservedObject var viewModel: MyViewModel
}

// @EnvironmentObject - shared state
@EnvironmentObject var settings: Settings

class UserViewModel: ObservableObject {
    @Published var name = ""
    @Published var email = ""
    @Published var isLoading = false
    
    func fetchUser() async {
        isLoading = true
        // Fetch data...
        isLoading = false
    }
}

struct ProfileView: View {
    @StateObject private var viewModel = UserViewModel()
    
    var body: some View {
        VStack {
            if viewModel.isLoading {
                ProgressView()
            } else {
                Text(viewModel.name)
            }
        }
        .task {
            await viewModel.fetchUser()
        }
    }
}

struct ContentView: View {
    var body: some View {
        NavigationStack {
            List(items) { item in
                NavigationLink(value: item) {
                    Text(item.name)
                }
            }
            .navigationTitle("Items")
            .navigationDestination(for: Item.self) { item in
                DetailView(item: item)
            }
        }
    }
}

// Programmatic navigation
@State private var path = NavigationPath()

NavigationStack(path: $path) {
    Button("Go to detail") {
        path.append(item)
    }
}

// Sheet
@State private var showSheet = false

Button("Show Sheet") {
    showSheet = true
}
.sheet(isPresented: $showSheet) {
    SheetView()
}

// Alert
@State private var showAlert = false

Button("Show Alert") {
    showAlert = true
}
.alert("Title", isPresented: $showAlert) {
    Button("OK") { }
    Button("Cancel", role: .cancel) { }
} message: {
    Text("Alert message")
}

struct ContentView: View {
    @State private var data: [Item] = []
    
    var body: some View {
        List(data) { item in
            Text(item.name)
        }
        .task {
            // Runs when view appears
            data = await fetchData()
        }
        .refreshable {
            // Pull to refresh
            data = await fetchData()
        }
    }
    
    func fetchData() async -> [Item] {
        let url = URL(string: "https://api.example.com/items")!
        let (data, _) = try! await URLSession.shared.data(from: url)
        return try! JSONDecoder().decode([Item].self, from: data)
    }
}