The Foundation Way — Same UI, a Fraction of the Code

Sign-in screen

Themed fields · validation · social row · forgot password

The old way138 lines

// Custom SignInView.swift — excerpt
struct SignInView: View {
  @State private var email = ""
  @State private var password = ""
  @State private var emailError: String?
  @State private var passwordError: String?
  @FocusState private var focused: Field?

  var body: some View {
    ScrollView {
      VStack(spacing: 24) {
        Text("Sign in")
          .font(.largeTitle.bold())
        // email field + border + error label
        VStack(alignment: .leading) {
          TextField("Email", text: $email)
            .textContentType(.emailAddress)
            .padding()
            .background(Color(.secondarySystemFill))
            .clipShape(RoundedRectangle(cornerRadius: 10))
          if let emailError { Text(emailError).foregroundStyle(.red) }
        }
        // secure field + reveal toggle + errors
        // primary button style, disabled state
        Button("Forgot password?") { }
        HStack { Divider(); Text("or"); Divider() }
        // Apple + Google custom buttons
        HStack {
          Text("Don't have an account?")
          Button("Sign up") { }
        }
      }.padding()
    }
    .onChange(of: email) { validateEmail() }
  }
  func validateEmail() { /* … */ }
  // + dark mode colors, macOS spacing, a11y labels…
}

The Foundation way13 lines

DFSignInBlock(
  configuration: .init(
    socialProviders: [
      .apple { await auth.signInWithApple() },
      .google { await auth.signInWithGoogle() }
    ],
    onSubmit: { email, password in
      await auth.signIn(email: email, password: password)
    },
    onForgotPassword: { path.append(.reset) },
    onSignUp: { path.append(.signUp) }
  )
)
// Validation, density, theme, macOS cursor — included.

127 lines saved · ~92% less ≈ 1,100 fewer tokens per auth screen in a typical AI rebuild

Dashboard KPI strip (3 metrics)

Trend arrows · icons · tap handlers · responsive grid

The old way96 lines

struct MetricTile: View {
  let title, value, trend: String
  let up: Bool
  var body: some View {
    VStack(alignment: .leading, spacing: 8) {
      HStack {
        Text(title).font(.caption).foregroundStyle(.secondary)
        Spacer()
        Image(systemName: "chart.line.uptrend.xyaxis")
      }
      Text(value).font(.title2.bold())
      HStack(spacing: 4) {
        Image(systemName: up ? "arrow.up" : "arrow.down")
        Text(trend).font(.caption)
      }.foregroundStyle(up ? .green : .red)
    }
    .padding()
    .background(Color(.secondarySystemBackground))
    .clipShape(RoundedRectangle(cornerRadius: 12))
  }
}

struct DashboardMetrics: View {
  var body: some View {
    LazyVGrid(columns: [...]) {
      MetricTile(...) // ×3
    }
  }
}

The Foundation way14 lines

DFMetricGridBlock(
  configuration: .init(
    metrics: [
      .init(title: "Revenue", value: "$48.2k", trend: "+12%", trendDirection: .up),
      .init(title: "Orders", value: "1,284", trend: "+3%", trendDirection: .up),
      .init(title: "Refunds", value: "0.8%", trend: "−0.2%", trendDirection: .down),
    ]
  )
)

82 lines saved · ~85% less Dashboard prompts shrink from “build 3 stat cards” to “wire DFMetricGridBlock”

Sortable table with multi-select

macOS keyboard nav · iPhone fallback · empty state

The old way204 lines

// ContactsTableView.swift — simplified
struct ContactsTableView: View {
  @State private var selection = Set<UUID>()
  @State private var sort: Sort = .name

  var body: some View {
    Group {
      #if os(macOS)
      Table(contacts, selection: $selection, sortOrder: $sort) {
        TableColumn("Name", value: \.name)
        TableColumn("Company", value: \.company)
      }
      #else
      List(contacts, selection: $selection) { c in
        HStack { Text(c.name); Spacer(); Text(c.company) }
      }
      #endif
    }
    .overlay { if contacts.isEmpty { EmptyStateView() } }
  }
}
// + filter hook, Return-to-open, toolbar bulk actions…

The Foundation way24 lines

DFDataTable(
  data: contacts,
  columns: [
    DFDataTableColumn(id: "name", title: "Name") { $0.name },
    DFDataTableColumn(id: "company", title: "Company") { $0.company },
    DFDataTableColumn(id: "status", title: "Status") { $0.status.label },
  ],
  selection: $selectedIDs,
  selectionMode: .multiple,
  filterQuery: searchText,
  onRowActivate: { openDetail($0) },
  emptyContent: {
    DFEmptyStateBlock(configuration: .init(
      icon: "person.crop.circle",
      title: "No contacts"
    ))
  }
)

180 lines saved · ~88% less Platform branching stays inside Foundation — not in your diff

E-commerce orders screen

Search · status chips · swipe actions · loading · empty

The old way~260 lines

// OrdersListView + OrderRow + StatusChip + filters
struct OrdersListView: View {
  @State private var query = ""
  @State private var filter: Status?
  var body: some View {
    NavigationStack {
      Group {
        if isLoading { ProgressView() }
        else if filtered.isEmpty { EmptyOrdersView() }
        else { List { /* rows */ } }
      }
      .searchable(text: $query)
      .toolbar { /* filter menu */ }
    }
  }
}
// Row layout, date formatting, badge colors, navigation…

The Foundation way16 lines

DFEcommerceOrdersScreen(
  configuration: .init(
    orders: viewModel.orders,
    isLoading: viewModel.isLoading,
    onSelectOrder: { viewModel.open($0) },
    onMarkShipped: { viewModel.markShipped($0) },
    onRefund: { viewModel.refund($0) }
  )
)

244 lines saved · ~94% less One import vs an entire vertical slice to spec in AI chat

Themed app root + toast feedback

Light/dark · macOS density · global notifications

The old way52 lines

extension Color {
  static let brandPrimary = Color("BrandPrimary")
  // asset catalog + dark variants…
}

struct ToastOverlay: ViewModifier { /* queue, auto-dismiss */ }

@main struct App: App {
  var body: some Scene {
    WindowGroup {
      RootView()
        .tint(.brandPrimary)
        .modifier(ToastOverlay())
    }
  }
}

The Foundation way7 lines

WindowGroup {
  RootView()
    .environment(\.dfTheme, .workspace)
    .environment(\.dfUseDesktopDensity, useDesktop)
    .dfToastHost()
}

45 lines saved · ~87% less Stop re-explaining your design tokens in every AI session

Methodology: “Old way” samples are representative production SwiftUI — themed, accessible, with validation and platform branches — not toy one-liners. “Foundation way” counts are what you type in your app module after adding the packages. Library implementation lives in DesignFoundation / Pro, tested once, shared everywhere.

The Foundation Way — same UI, a fraction of the code

Write less. Ship the same.