Swift untuk iOS Development

// ===== Variabel dan Konstanta =====
// var → bisa diubah (mutable)
// let → tidak bisa diubah (immutable/constant)

var nama = "Budi"           // String, type inference
let umur = 25               // Int, type inference
var tinggi: Double = 175.5  // Double, explicit type
let isActive = true         // Bool

nama = "Andi"     // ✅ Bisa diubah
// umur = 30      // ❌ Error: cannot assign to 'let'

// ===== Tipe Data Dasar =====
let angka: Int = 42
let desimal: Double = 3.14
let huruf: Character = "A"
let teks: String = "Hello, World!"
let flag: Bool = true

// ===== String Operations =====
let firstName = "Budi"
let lastName = "Santoso"
let fullName = firstName + " " + lastName  // Concatenation
let greeting = "Halo, \(firstName)!"       // String interpolation
let multiLine = """
    Ini adalah string
    multi-line
    di Swift
    """

print(fullName)    // Budi Santoso
print(greeting)    // Halo, Budi!
print(teks.count)  // 13

// ===== Collections =====
// Array — urut, bisa duplikat
var buah = ["Apel", "Mangga", "Jeruk"]
buah.append("Durian")       // Tambah di akhir
buah.insert("Anggur", at: 1) // Tambah di index tertentu
buah.remove(at: 0)           // Hapus di index
print(buah.count)             // 4
print(buah[0])                // Mangga

// Dictionary — key-value pairs
var mahasiswa: [String: Any] = [
    "nama": "Sari",
    "umur": 22,
    "jurusan": "Informatika"
]
mahasiswa["ipk"] = 3.85    // Tambah entry baru
print(mahasiswa["nama"]!)  // Sari (pakai ! untuk unwrap)

// Set — unik, tidak berurutan
var angkaUnik: Set = [1, 2, 3, 2, 1]
print(angkaUnik)  // {1, 2, 3} (duplikat dihapus)

// Tuples — group beberapa nilai
let koordinat = (lat: -6.2088, lng: 106.8456)
print("Latitude: \(koordinat.lat)")
print("Longitude: \(koordinat.lng)")

// ===== IF-ELSE =====
let nilai = 85

if nilai >= 90 {
    print("A — Excellent")
} else if nilai >= 80 {
    print("B — Good")
} else if nilai >= 70 {
    print("C — Average")
} else {
    print("D — Below Average")
}

// ===== SWITCH (lebih powerful di Swift) =====
let cuaca = "hujan"

switch cuaca {
case "cerah":
    print("Cuaca bagus! ☀️")
case "hujan":
    print("Bawa payung! 🌧️")
case "mendung":
    print("Mungkin akan hujan ☁️")
default:
    print("Cek prakiraan cuaca 📱")
}

// Switch dengan range
switch nilai {
case 90...100:
    print("A")
case 80..<90:
    print("B")
case 70..<80:
    print("C")
default:
    print("D")
}

// ===== LOOPS =====
// For-in loop
for i in 1...5 {
    print("Iterasi ke-\(i)")
}

// Loop dengan array
let warna = ["Merah", "Hijau", "Biru"]
for w in warna {
    print("Warna: \(w)")
}

// While loop
var counter = 0
while counter < 3 {
    print("Counter: \(counter)")
    counter += 1
}

// ===== FUNCTIONS =====
func sapaan(nama: String) -> String {
    return "Halo, \(nama)! Selamat datang."
}

print(sapaan(nama: "Budi"))

// Function dengan default parameter
func hitungLuas(panjang: Double, lebar: Double = 10.0) -> Double {
    return panjang * lebar
}

print(hitungLuas(panjang: 5.0))         // 50.0 (lebar default 10)
print(hitungLuas(panjang: 5.0, lebar: 3.0))  // 15.0

// Function dengan multiple return values
func statistik(angka: [Int]) -> (min: Int, max: Int, avg: Double) {
    let minVal = angka.min()!
    let maxVal = angka.max()!
    let avgVal = Double(angka.reduce(0, +)) / Double(angka.count)
    return (minVal, maxVal, avgVal)
}

let data = [10, 20, 30, 40, 50]
let stat = statistik(angka: data)
print("Min: \(stat.min), Max: \(stat.max), Avg: \(stat.avg)")

// ===== CLOSURES =====
let angkaArr = [5, 2, 8, 1, 9, 3]

// Sorting dengan closure
let sorted = angkaArr.sorted { $0 < $1 }
print(sorted)  // [1, 2, 3, 5, 8, 9]

// Map, Filter, Reduce
let doubled = angkaArr.map { $0 * 2 }
let ganjil = angkaArr.filter { $0 % 2 != 0 }
let total = angkaArr.reduce(0) { $0 + $1 }

print(doubled)  // [10, 4, 16, 2, 18, 6]
print(ganjil)   // [5, 1, 9, 3]
print(total)    // 28

// ===== Optionals =====
// Optional = bisa ada nilai atau nil
var namaLengkap: String? = "Budi Santoso"
var emailKosong: String? = nil

// Force unwrap (berbahaya!)
// print(namaLengkap!)  // OK, tapi crash jika nil

// Optional binding (safe)
if let nama = namaLengkap {
    print("Nama: \(nama)")
} else {
    print("Nama tidak tersedia")
}

// Guard let (early exit)
func prosesEmail(_ email: String?) {
    guard let email = email else {
        print("Email tidak valid")
        return
    }
    print("Mengirim email ke: \(email)")
}

// Nil coalescing
let displayName = namaLengkap ?? "Anonymous"
print(displayName)  // Budi Santoso

// Optional chaining
struct Alamat {
    var kota: String
    var kodePos: String
}

struct Orang {
    var nama: String
    var alamat: Alamat?
}

let budi = Orang(nama: "Budi", alamat: Alamat(kota: "Jakarta", kodePos: "12345"))
let sari = Orang(nama: "Sari", alamat: nil)

print(budi.alamat?.kota ?? "Tidak diketahui")  // Jakarta
print(sari.alamat?.kota ?? "Tidak diketahui")  // Tidak diketahui

// ===== Error Handling =====
enum NetworkError: Error {
    case noConnection
    case timeout
    case serverError(code: Int)
}

func fetchData(from url: String) throws -> String {
    if url.isEmpty {
        throw NetworkError.noConnection
    }
    if url.contains("timeout") {
        throw NetworkError.timeout
    }
    return "Data dari \(url)"
}

do {
    let data = try fetchData(from: "https://api.example.com")
    print(data)
} catch NetworkError.noConnection {
    print("Tidak ada koneksi internet")
} catch NetworkError.timeout {
    print("Request timeout")
} catch {
    print("Error: \(error)")
}

MyApp/
├── MyApp/
│   ├── MyAppApp.swift          ← Entry point aplikasi (@main)
│   ├── ContentView.swift       ← View utama
│   ├── Models/                 ← Data models
│   │   └── User.swift
│   ├── Views/                  ← UI Views
│   │   ├── HomeView.swift
│   │   ├── DetailView.swift
│   │   └── ProfileView.swift
│   ├── ViewModels/             ← View Models (MVVM)
│   │   └── UserViewModel.swift
│   ├── Services/               ← Network, API calls
│   │   └── APIService.swift
│   ├── Assets.xcassets/        ← Gambar, warna, icons
│   │   ├── AppIcon.appiconset/
│   │   └── AccentColor.colorset/
│   ├── Info.plist              ← Konfigurasi aplikasi
│   └── Localizable.strings    ← Translasi bahasa
├── MyApp.xcodeproj            ← Project file Xcode
├── MyAppTests/                ← Unit tests
└── MyAppUITests/              ← UI tests

import UIKit

class ViewController: UIViewController {
    
    // UI Elements
    let titleLabel = UILabel()
    let nameTextField = UITextField()
    let submitButton = UIButton(type: .system)
    let resultLabel = UILabel()
    
    override func viewDidLoad() {
        super.viewDidLoad()
        view.backgroundColor = .systemBackground
        setupUI()
    }
    
    func setupUI() {
        // ===== Title Label =====
        titleLabel.text = "Selamat Datang!"
        titleLabel.font = UIFont.systemFont(ofSize: 28, weight: .bold)
        titleLabel.textColor = .label
        titleLabel.textAlignment = .center
        titleLabel.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(titleLabel)
        
        // ===== Text Field =====
        nameTextField.placeholder = "Masukkan nama Anda"
        nameTextField.borderStyle = .roundedRect
        nameTextField.font = UIFont.systemFont(ofSize: 16)
        nameTextField.autocorrectionType = .no
        nameTextField.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(nameTextField)
        
        // ===== Submit Button =====
        submitButton.setTitle("Sapa!", for: .normal)
        submitButton.titleLabel?.font = UIFont.systemFont(ofSize: 18, weight: .medium)
        submitButton.backgroundColor = .systemBlue
        submitButton.setTitleColor(.white, for: .normal)
        submitButton.layer.cornerRadius = 10
        submitButton.addTarget(self, action: #selector(buttonTapped), for: .touchUpInside)
        submitButton.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(submitButton)
        
        // ===== Result Label =====
        resultLabel.text = ""
        resultLabel.font = UIFont.systemFont(ofSize: 20, weight: .medium)
        resultLabel.textColor = .systemGreen
        resultLabel.textAlignment = .center
        resultLabel.numberOfLines = 0
        resultLabel.translatesAutoresizingMaskIntoConstraints = false
        view.addSubview(resultLabel)
        
        // ===== Auto Layout Constraints =====
        NSLayoutConstraint.activate([
            titleLabel.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            titleLabel.topAnchor.constraint(equalTo: view.safeAreaLayoutGuide.topAnchor, constant: 40),
            
            nameTextField.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            nameTextField.topAnchor.constraint(equalTo: titleLabel.bottomAnchor, constant: 30),
            nameTextField.widthAnchor.constraint(equalToConstant: 280),
            nameTextField.heightAnchor.constraint(equalToConstant: 44),
            
            submitButton.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            submitButton.topAnchor.constraint(equalTo: nameTextField.bottomAnchor, constant: 20),
            submitButton.widthAnchor.constraint(equalToConstant: 200),
            submitButton.heightAnchor.constraint(equalToConstant: 50),
            
            resultLabel.centerXAnchor.constraint(equalTo: view.centerXAnchor),
            resultLabel.topAnchor.constraint(equalTo: submitButton.bottomAnchor, constant: 30),
            resultLabel.leadingAnchor.constraint(equalTo: view.leadingAnchor, constant: 20),
            resultLabel.trailingAnchor.constraint(equalTo: view.trailingAnchor, constant: -20),
        ])
    }
    
    @objc func buttonTapped() {
        guard let name = nameTextField.text, !name.isEmpty else {
            resultLabel.text = "⚠️ Masukkan nama terlebih dahulu"
            resultLabel.textColor = .systemRed
            return
        }
        
        resultLabel.text = "Halo, \(name)! 👋 Selamat belajar iOS!"
        resultLabel.textColor = .systemGreen
        nameTextField.resignFirstResponder() // Tutup keyboard
    }
}

// ===== UITableView Contoh =====
class DaftarViewController: UIViewController, UITableViewDataSource, UITableViewDelegate {
    
    let tableView = UITableView()
    let items = ["iPhone 16", "iPhone 16 Pro", "iPad Pro", "MacBook Air", "Apple Watch"]
    
    override func viewDidLoad() {
        super.viewDidLoad()
        title = "Produk Apple"
        
        tableView.dataSource = self
        tableView.delegate = self
        tableView.register(UITableViewCell.self, forCellReuseIdentifier: "cell")
        tableView.frame = view.bounds
        tableView.autoresizingMask = [.flexibleWidth, .flexibleHeight]
        view.addSubview(tableView)
    }
    
    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return items.count
    }
    
    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let cell = tableView.dequeueReusableCell(withIdentifier: "cell", for: indexPath)
        cell.textLabel?.text = items[indexPath.row]
        cell.accessoryType = .disclosureIndicator
        return cell
    }
    
    func tableView(_ tableView: UITableView, didSelectRowAt indexPath: IndexPath) {
        tableView.deselectRow(at: indexPath, animated: true)
        print("Dipilih: \(items[indexPath.row])")
    }
}

import SwiftUI

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

// ===== Basic View =====
struct ContentView: View {
    var body: some View {
        Text("Halo, SwiftUI! 🎉")
            .font(.largeTitle)
            .fontWeight(.bold)
            .foregroundColor(.blue)
    }
}

// ===== View dengan State =====
struct CounterView: View {
    @State private var count = 0
    
    var body: some View {
        VStack(spacing: 20) {
            Text("Hitungan: \(count)")
                .font(.system(size: 32, weight: .semibold))
            
            HStack(spacing: 20) {
                Button("Kurang (-)") {
                    count -= 1
                }
                .buttonStyle(.bordered)
                .tint(.red)
                
                Button("Reset") {
                    count = 0
                }
                .buttonStyle(.bordered)
                
                Button("Tambah (+)") {
                    count += 1
                }
                .buttonStyle(.bordered)
                .tint(.green)
            }
        }
        .padding()
    }
}

// ===== List & Data =====
struct TodoItem: Identifiable {
    let id = UUID()
    var title: String
    var isDone: Bool
}

struct TodoListView: View {
    @State private var todos = [
        TodoItem(title: "Belajar SwiftUI", isDone: false),
        TodoItem(title: "Buat proyek pertama", isDone: false),
        TodoItem(title: "Submit ke App Store", isDone: false),
    ]
    @State private var newTodo = ""
    
    var body: some View {
        NavigationView {
            VStack {
                // Input field
                HStack {
                    TextField("Tambah tugas baru...", text: $newTodo)
                        .textFieldStyle(.roundedBorder)
                    
                    Button("Tambah") {
                        guard !newTodo.isEmpty else { return }
                        todos.append(TodoItem(title: newTodo, isDone: false))
                        newTodo = ""
                    }
                    .buttonStyle(.borderedProminent)
                }
                .padding()
                
                // List
                List {
                    ForEach(todos) { todo in
                        HStack {
                            Image(systemName: todo.isDone ? "checkmark.circle.fill" : "circle")
                                .foregroundColor(todo.isDone ? .green : .gray)
                            
                            Text(todo.title)
                                .strikethrough(todo.isDone)
                        }
                        .onTapGesture {
                            if let index = todos.firstIndex(where: { $0.id == todo.id }) {
                                todos[index].isDone.toggle()
                            }
                        }
                    }
                    .onDelete { indexSet in
                        todos.remove(atOffsets: indexSet)
                    }
                }
            }
            .navigationTitle("📋 Daftar Tugas")
        }
    }
}

// ===== Form & Input =====
struct ProfilView: View {
    @State private var nama = ""
    @State private var email = ""
    @State private var umur = 18.0
    @State private var notifikasi = true
    @State private var tema = 0
    
    let temaOptions = ["Terang", "Gelap", "Otomatis"]
    
    var body: some View {
        NavigationView {
            Form {
                Section("Informasi Pribadi") {
                    TextField("Nama", text: $nama)
                    TextField("Email", text: $email)
                        .keyboardType(.emailAddress)
                    
                    VStack(alignment: .leading) {
                        Text("Umur: \(Int(umur)) tahun")
                        Slider(value: $umur, in: 17...80, step: 1)
                    }
                }
                
                Section("Pengaturan") {
                    Toggle("Notifikasi", isOn: $notifikasi)
                    
                    Picker("Tema", selection: $tema) {
                        ForEach(0..
      

import SwiftUI

// ===== Model =====
struct Produk: Identifiable, Hashable {
    let id = UUID()
    let nama: String
    let harga: Int
    let deskripsi: String
    let emoji: String
}

// ===== NavigationStack dengan NavigationLink =====
struct KatalogView: View {
    let produkList = [
        Produk(nama: "iPhone 16", harga: 15999000, deskripsi: "Smartphone terbaru Apple", emoji: "📱"),
        Produk(nama: "MacBook Air M3", harga: 19999000, deskripsi: "Laptop tipis dan powerful", emoji: "💻"),
        Produk(nama: "iPad Pro", harga: 14999000, deskripsi: "Tablet profesional", emoji: "📲"),
        Produk(nama: "Apple Watch", harga: 7999000, deskripsi: "Smartwatch canggih", emoji: "⌚"),
        Produk(nama: "AirPods Pro", harga: 4299000, deskripsi: "Earbuds dengan ANC", emoji: "🎧"),
    ]
    
    @State private var searchText = ""
    
    var filteredProduk: [Produk] {
        if searchText.isEmpty {
            return produkList
        }
        return produkList.filter { $0.nama.localizedCaseInsensitiveContains(searchText) }
    }
    
    var body: some View {
        NavigationStack {
            List(filteredProduk) { produk in
                NavigationLink(value: produk) {
                    HStack {
                        Text(produk.emoji)
                            .font(.system(size: 40))
                        
                        VStack(alignment: .leading, spacing: 4) {
                            Text(produk.nama)
                                .font(.headline)
                            Text("Rp \(produk.harga.formatted())")
                                .font(.subheadline)
                                .foregroundColor(.secondary)
                        }
                    }
                    .padding(.vertical, 4)
                }
            }
            .navigationTitle("🛒 Katalog")
            .searchable(text: $searchText, prompt: "Cari produk...")
            .navigationDestination(for: Produk.self) { produk in
                DetailProdukView(produk: produk)
            }
        }
    }
}

// ===== Detail View =====
struct DetailProdukView: View {
    let produk: Produk
    @State private var quantity = 1
    @Environment(\.dismiss) var dismiss
    
    var body: some View {
        ScrollView {
            VStack(alignment: .leading, spacing: 20) {
                // Hero image placeholder
                Text(produk.emoji)
                    .font(.system(size: 100))
                    .frame(maxWidth: .infinity)
                    .padding(.vertical, 40)
                    .background(Color(.systemGray6))
                    .cornerRadius(16)
                
                VStack(alignment: .leading, spacing: 8) {
                    Text(produk.nama)
                        .font(.title)
                        .fontWeight(.bold)
                    
                    Text("Rp \(produk.harga.formatted())")
                        .font(.title2)
                        .foregroundColor(.blue)
                        .fontWeight(.semibold)
                    
                    Text(produk.deskripsi)
                        .font(.body)
                        .foregroundColor(.secondary)
                }
                
                // Quantity stepper
                HStack {
                    Text("Jumlah:")
                        .font(.headline)
                    
                    Stepper("\(quantity)", value: $quantity, in: 1...10)
                }
                
                // Total price
                HStack {
                    Text("Total:")
                        .font(.headline)
                    Spacer()
                    Text("Rp \((produk.harga * quantity).formatted())")
                        .font(.title3)
                        .fontWeight(.bold)
                        .foregroundColor(.blue)
                }
                
                // Buy button
                Button(action: {
                    print("Membeli \(quantity)x \(produk.nama)")
                }) {
                    Text("🛒 Beli Sekarang")
                        .font(.headline)
                        .foregroundColor(.white)
                        .frame(maxWidth: .infinity)
                        .padding()
                        .background(Color.blue)
                        .cornerRadius(12)
                }
            }
            .padding()
        }
        .navigationTitle(produk.nama)
        .navigationBarTitleDisplayMode(.inline)
    }
}

// ===== Sheet / Modal Presentation =====
struct MainView: View {
    @State private var showProfile = false
    @State private var showSettings = false
    
    var body: some View {
        VStack(spacing: 20) {
            Text("🏠 Beranda")
                .font(.largeTitle)
            
            Button("👤 Profil") {
                showProfile = true
            }
            .buttonStyle(.borderedProminent)
            
            Button("⚙️ Pengaturan") {
                showSettings = true
            }
            .buttonStyle(.bordered)
        }
        .sheet(isPresented: $showProfile) {
            ProfilView()
        }
        .sheet(isPresented: $showSettings) {
            NavigationView {
                Text("Pengaturan Aplikasi")
                    .navigationTitle("Pengaturan")
                    .navigationBarTitleDisplayMode(.inline)
                    .toolbar {
                        ToolbarItem(placement: .navigationBarLeading) {
                            Button("Tutup") { showSettings = false }
                        }
                    }
            }
        }
    }
}

import SwiftUI

// ===== 1. UserDefaults (data kecil) =====
class AppSettings: ObservableObject {
    @AppStorage("username") var username: String = ""
    @AppStorage("isDarkMode") var isDarkMode: Bool = false
    @AppStorage("fontSize") var fontSize: Double = 16.0
    @AppStorage("language") var language: String = "id"
}

struct SettingsView: View {
    @StateObject private var settings = AppSettings()
    
    var body: some View {
        Form {
            Section("Profil") {
                TextField("Username", text: $settings.username)
            }
            
            Section("Tampilan") {
                Toggle("Dark Mode", isOn: $settings.isDarkMode)
                
                VStack {
                    Text("Font Size: \(Int(settings.fontSize))pt")
                    Slider(value: $settings.fontSize, in: 12...24, step: 1)
                }
            }
            
            Section("Bahasa") {
                Picker("Bahasa", selection: $settings.language) {
                    Text("Indonesia").tag("id")
                    Text("English").tag("en")
                    Text("日本語").tag("ja")
                }
            }
        }
        .navigationTitle("Pengaturan")
    }
}

// ===== 2. Codable — Simpan/Load JSON =====
struct Catatan: Codable, Identifiable {
    let id: UUID
    var judul: String
    var isi: String
    var tanggal: Date
}

class CatatanManager {
    private let fileName = "catatan.json"
    
    // Dapatkan path file di Documents directory
    private var fileURL: URL {
        FileManager.default.urls(for: .documentDirectory, in: .userDomainMask)[0]
            .appendingPathComponent(fileName)
    }
    
    // Simpan catatan ke file
    func simpan(_ catatan: [Catatan]) {
        do {
            let data = try JSONEncoder().encode(catatan)
            try data.write(to: fileURL)
            print("✅ \(catatan.count) catatan tersimpan")
        } catch {
            print("❌ Gagal menyimpan: \(error)")
        }
    }
    
    // Muat catatan dari file
    func muat() -> [Catatan] {
        do {
            let data = try Data(contentsOf: fileURL)
            let catatan = try JSONDecoder().decode([Catatan].self, from: data)
            return catatan
        } catch {
            print("📂 Tidak ada catatan tersimpan atau file corrupt")
            return []
        }
    }
}

// ===== 3. SwiftData (iOS 17+) =====
import SwiftData

@Model
class TaskItem {
    var id: UUID
    var title: String
    var isCompleted: Bool
    var createdAt: Date
    
    init(title: String) {
        self.id = UUID()
        self.title = title
        self.isCompleted = false
        self.createdAt = Date()
    }
}

struct TaskListView: View {
    @Environment(\.modelContext) private var modelContext
    @Query(sort: \TaskItem.createdAt, order: .reverse) private var tasks: [TaskItem]
    @State private var newTaskTitle = ""
    
    var body: some View {
        NavigationStack {
            VStack {
                HStack {
                    TextField("Tugas baru...", text: $newTaskTitle)
                        .textFieldStyle(.roundedBorder)
                    
                    Button("Tambah") {
                        guard !newTaskTitle.isEmpty else { return }
                        let task = TaskItem(title: newTaskTitle)
                        modelContext.insert(task)
                        newTaskTitle = ""
                    }
                    .buttonStyle(.borderedProminent)
                }
                .padding()
                
                List {
                    ForEach(tasks) { task in
                        HStack {
                            Image(systemName: task.isCompleted ? "checkmark.circle.fill" : "circle")
                                .foregroundColor(task.isCompleted ? .green : .gray)
                                .onTapGesture {
                                    task.isCompleted.toggle()
                                }
                            
                            Text(task.title)
                                .strikethrough(task.isCompleted)
                        }
                    }
                    .onDelete { indexSet in
                        for index in indexSet {
                            modelContext.delete(tasks[index])
                        }
                    }
                }
            }
            .navigationTitle("📋 Tugas (SwiftData)")
        }
    }
}

// App entry point dengan SwiftData
@main
struct TaskApp: App {
    var body: some Scene {
        WindowGroup {
            TaskListView()
        }
        .modelContainer(for: TaskItem.self)
    }
}