SwiftUI 用户界面

// 基本文本
Text("Hello, World!")
    .font(.title)
    .bold()

// 标签
Label("用户名", systemImage: "person.circle")

// 可编辑文本
TextEditor(text: $notes)
    .frame(height: 100)

// 基本按钮
Button("点击我") {
    print("按钮被点击")
}

// 自定义按钮
Button(action: handleTap) {
    HStack {
        Image(systemName: "star.fill")
        Text("收藏")
    }
    .padding()
    .background(Color.blue)
    .foregroundColor(.white)
    .cornerRadius(8)
}

// 开关
Toggle("通知", isOn: $isNotificationEnabled)

// 滑块
Slider(value: $volume, in: 0...100)

// 步进器
Stepper("数量: \(quantity)",
        value: $quantity,
        in: 1...10)

List {
    Text("第一项")
    Text("第二项")
    Text("第三项")
}

// 动态列表
List(items, id: \.id) { item in
    Text(item.title)
}

// 分组列表
List {
    Section(header: Text("收藏")) {
        ForEach(favoriteItems) { item in
            ItemRow(item: item)
        }
    }

    Section(header: Text("推荐")) {
        ForEach(recommendedItems) { item in
            ItemRow(item: item)
        }
    }
}

ScrollView {
    VStack(spacing: 20) {
        ForEach(0..<50) { i in
            Text("项目 \(i)")
        }
    }
}

// 水平滚动
ScrollView(.horizontal, showsIndicators: false) {
    HStack(spacing: 15) {
        ForEach(images, id: \.self) { image in
            Image(image)
                .resizable()
                .frame(width: 200, height: 200)
        }
    }
}

NavigationView {
    List(items) { item in
        NavigationLink(destination: DetailView(item: item)) {
            Text(item.title)
        }
    }
    .navigationTitle("我的列表")
    .navigationBarItems(
        trailing: Button(action: addItem) {
            Image(systemName: "plus")
        }
    )
}

TabView {
    HomeView()
        .tabItem {
            Label("首页", systemImage: "house")
        }

    ProfileView()
        .tabItem {
            Label("我的", systemImage: "person")
        }
}

// 点击手势
Text("点击我")
    .onTapGesture {
        print("被点击了")
    }

// 长按手势
Image("photo")
    .onLongPressGesture(minimumDuration: 1) {
        print("长按触发")
    }

// 拖拽手势
Circle()
    .fill(Color.blue)
    .frame(width: 100, height: 100)
    .offset(offset)
    .gesture(
        DragGesture()
            .onChanged { value in
                offset = value.translation
            }
            .onEnded { _ in
                withAnimation {
                    offset = .zero
                }
            }
    )

struct Photo: Identifiable {
    let id = UUID()
    let name: String
    let image: String
}

struct PhotoGallery: View {
    let photos = [
        Photo(name: "风景1", image: "landscape1"),
        Photo(name: "风景2", image: "landscape2"),
        Photo(name: "风景3", image: "landscape3")
    ]

    @State private var selectedPhoto: Photo?

    var body: some View {
        NavigationView {
            ScrollView {
                LazyVGrid(columns: [
                    GridItem(.flexible()),
                    GridItem(.flexible()),
                    GridItem(.flexible())
                ], spacing: 10) {
                    ForEach(photos) { photo in
                        Image(photo.image)
                            .resizable()
                            .aspectRatio(contentMode: .fill)
                            .frame(height: 120)
                            .clipped()
                            .cornerRadius(8)
                            .onTapGesture {
                                selectedPhoto = photo
                            }
                    }
                }
                .padding()
            }
            .navigationTitle("照片库")
            .sheet(item: $selectedPhoto) { photo in
                PhotoDetailView(photo: photo)
            }
        }
    }
}

struct PhotoDetailView: View {
    let photo: Photo
    @Environment(\.presentationMode) var presentationMode

    var body: some View {
        VStack {
            Image(photo.image)
                .resizable()
                .aspectRatio(contentMode: .fit)

            Text(photo.name)
                .font(.title)

            Button("关闭") {
                presentationMode.wrappedValue.dismiss()
            }
            .padding()
        }
    }
}