Widgetkit

WidgetKit

Build home screen widgets, Lock Screen widgets, Control Center controls, and StandBy or CarPlay widget surfaces for iOS 26+.

Keep adjacent-framework guidance scoped to WidgetKit integration. Include ActivityKit and App Intents only where they connect directly to WidgetKit surfaces; hand off full lifecycle, APNs content-state, Siri/Shortcuts/Spotlight, or entity-modeling work to sibling activitykit or app-intents skills.

See references/widgetkit-advanced.md for timeline strategies, push-based updates, Xcode setup, and advanced patterns.

Contents

• Workflow
• Widget Protocol and WidgetBundle
• Configuration Types
• TimelineProvider
• AppIntentTimelineProvider
• Widget Families
• Interactive Widgets (iOS 17+)
• ActivityConfiguration Handoff
• Control Center Widgets (iOS 18+)
• Lock Screen Widgets
• StandBy Mode
• Widget URL Handling and Deep Links
• Smart Stack Relevance
• Design Patterns
• iOS 26 Additions
• Common Mistakes
• Review Checklist
• References

Workflow

1. Create a new widget

1. Add a Widget Extension target in Xcode (File > New > Target > Widget Extension). 2. Enable App Groups for shared data between the app and widget extension. 3. Define a TimelineEntry struct with a date property and display data. 4. Implement a TimelineProvider (static) or AppIntentTimelineProvider (configurable). 5. Build the widget view using SwiftUI, adapting layout per WidgetFamily. 6. Declare the Widget conforming struct with a configuration and supported families. 7. Register all widgets in a WidgetBundle annotated with @main.

2. Integrate adjacent surfaces

1. Register an ActivityConfiguration in the widget bundle when the app has a Live Activity, but keep ActivityAttributes, request/update/end, APNs content-state, and Dynamic Island layout depth in activitykit. 2. Place Button, Toggle, ControlWidgetButton, and ControlWidgetToggle in WidgetKit views or controls, but keep intent modeling, entities, queries, Siri, Shortcuts, and Spotlight in app-intents.

3. Add a Control Center control

1. Reuse an AppIntent/OpenIntent for a button, or a SetValueIntent for a toggle. 2. Create a ControlWidgetButton or ControlWidgetToggle in the widget bundle. 3. Use StaticControlConfiguration or AppIntentControlConfiguration.

4. Review existing widget code

Run through the Review Checklist at the end of this document.

Widget Protocol and WidgetBundle

Widget

Every widget conforms to the Widget protocol and returns a WidgetConfiguration from its body.

struct OrderStatusWidget: Widget {
    let kind: String = "OrderStatusWidget"

    var body: some WidgetConfiguration {
        StaticConfiguration(kind: kind, provider: OrderProvider()) { entry in
            OrderWidgetView(entry: entry)
        }
        .configurationDisplayName("Order Status")
        .description("Track your current order.")
        .supportedFamilies([.systemSmall, .systemMedium])
    }
}

WidgetBundle

Use WidgetBundle to expose multiple widgets from a single extension.

@main
struct MyAppWidgets: WidgetBundle {
    var body: some Widget {
        OrderStatusWidget()
        FavoritesWidget()
        DeliveryActivityWidget()   // ActivityConfiguration handoff
        QuickActionControl()       // Control Center
    }
}

Configuration Types

Use StaticConfiguration for non-configurable widgets. Use AppIntentConfiguration (recommended) for configurable widgets paired with AppIntentTimelineProvider.

// Static
StaticConfiguration(kind: "MyWidget", provider: MyProvider()) { entry in
    MyWidgetView(entry: entry)
}
// Configurable
AppIntentConfiguration(kind: "ConfigWidget", intent: SelectCategoryIntent.self,
                       provider: CategoryProvider()) { entry in
    CategoryWidgetView(entry: entry)
}

Shared Modifiers

TimelineProvider

For static (non-configurable) widgets. Uses completion handlers. Three required methods:

struct WeatherProvider: TimelineProvider {
    typealias Entry = WeatherEntry

    func placeholder(in context: Context) -> WeatherEntry {
        WeatherEntry(date: .now, temperature: 72, condition: "Sunny")
    }

    func getSnapshot(in context: Context, completion: @escaping (WeatherEntry) -> Void) {
        let entry = context.isPreview
            ? placeholder(in: context)
            : WeatherEntry(date: .now, temperature: currentTemp, condition: currentCondition)
        completion(entry)
    }

    func getTimeline(in context: Context, completion: @escaping (Timeline<WeatherEntry>) -> Void) {
        Task {
            let weather = await WeatherService.shared.fetch()
            let entry = WeatherEntry(date: .now, temperature: weather.temp, condition: weather.condition)
            let nextUpdate = Calendar.current.date(byAdding: .hour, value: 1, to: .now)!
            completion(Timeline(entries: [entry], policy: .after(nextUpdate)))
        }
    }
}

AppIntentTimelineProvider

For configurable widgets. Uses async/await natively. Receives user intent configuration.

struct CategoryProvider: AppIntentTimelineProvider {
    typealias Entry = CategoryEntry
    typealias Intent = SelectCategoryIntent

    func placeholder(in context: Context) -> CategoryEntry {
        CategoryEntry(date: .now, categoryName: "Sample", items: [])
    }

    func snapshot(for config: SelectCategoryIntent, in context: Context) async -> CategoryEntry {
        let items = await DataStore.shared.items(for: config.category)
        return CategoryEntry(date: .now, categoryName: config.category.name, items: items)
    }

    func timeline(for config: SelectCategoryIntent, in context: Context) async -> Timeline<CategoryEntry> {
        let items = await DataStore.shared.items(for: config.category)
        let entry = CategoryEntry(date: .now, categoryName: config.category.name, items: items)
        return Timeline(entries: [entry], policy: .atEnd)
    }
}

Widget Families

Adapt layout per family using @Environment(\.widgetFamily):

@Environment(\.widgetFamily) var family

var body: some View {
    switch family {
    case .systemSmall: CompactView(entry: entry)
    case .systemMedium: DetailedView(entry: entry)
    case .accessoryCircular: CircularView(entry: entry)
    default: FullView(entry: entry)
    }
}

Interactive Widgets (iOS 17+)

Use Button and Toggle with intent types available to the widget extension or shared code. WidgetKit owns the view placement; app-intents owns intent modeling and behavior.

struct InteractiveWidgetView: View {
    let entry: FavoriteEntry

    var body: some View {
        Button(intent: ToggleFavoriteIntent(itemID: entry.itemID)) {
            Image(systemName: entry.isFavorite ? "star.fill" : "star")
        }
    }
}

ActivityConfiguration Handoff

WidgetKit registers Live Activity surfaces in the widget extension. Keep this section to registration and rendering handoff; use activitykit for ActivityAttributes, lifecycle, push updates, and full Dynamic Island patterns.

struct DeliveryActivityWidget: Widget {
    var body: some WidgetConfiguration {
        ActivityConfiguration(for: DeliveryAttributes.self) { context in
            DeliveryLiveActivityView(context: context)
        } dynamicIsland: { context in
            DeliveryDynamicIsland(context: context)
        }
    }
}

Control Center Widgets (iOS 18+)

WidgetKit owns control configuration, placement, kind, display name, push handler, and extension registration. Control actions and value intents belong in app-intents.

struct OpenCameraControl: ControlWidget {
    var body: some ControlWidgetConfiguration {
        StaticControlConfiguration(kind: "OpenCamera") {
            ControlWidgetButton(action: OpenCameraIntent()) {
                Label("Camera", systemImage: "camera.fill")
            }
        }
        .displayName("Open Camera")
    }
}

struct FlashlightControl: ControlWidget {
    var body: some ControlWidgetConfiguration {
        StaticControlConfiguration(kind: "Flashlight", provider: FlashlightValueProvider()) { value in
            ControlWidgetToggle(isOn: value, action: ToggleFlashlightIntent()) {
                Label("Flashlight", systemImage: value ? "flashlight.on.fill" : "flashlight.off.fill")
            }
        }
        .displayName("Flashlight")
    }
}

Lock Screen Widgets

Use accessory families and AccessoryWidgetBackground.

struct StepsWidget: Widget {
    let kind = "StepsWidget"
    var body: some WidgetConfiguration {
        StaticConfiguration(kind: kind, provider: StepsProvider()) { entry in
            ZStack {
                AccessoryWidgetBackground()
                VStack {
                    Image(systemName: "figure.walk")
                    Text("\(entry.stepCount)").font(.headline)
                }
            }
        }
        .supportedFamilies([.accessoryCircular, .accessoryRectangular, .accessoryInline])
    }
}

StandBy Mode

Small system widgets can appear in StandBy and CarPlay. Use @Environment(\.widgetLocation) for conditional rendering:

@Environment(\.widgetLocation) var location
// location == .standBy, .homeScreen, .lockScreen, .carPlay, etc.

Widget URL Handling and Deep Links

Use one .widgetURL(_:) as the whole-widget fallback route. Use Link for deliberate subtargets only where the family and layout support them, including .accessoryRectangular, .systemSmall, and larger system widgets. For small widgets, prefer one clear fallback; avoid multiple Link targets unless the visual affordance and hit areas remain unambiguous.

Never attach multiple widgetURL modifiers in the hierarchy.

Smart Stack Relevance

Use TimelineEntryRelevance(score:duration:) on timeline entries for timely iPhone and iPad Smart Stack relevance. Keep scores on a consistent positive scale; zero or lower means not relevant.

For configurable widgets, donate App Intents that correspond to user actions or widget parameters from app-side code, such as with intent.donate() or IntentDonationManager. Keep AppEntity and EntityQuery design in app-intents.

On watchOS, contextual relevance uses WidgetRelevance([WidgetRelevanceAttribute(...)]) from the provider relevance() callback. That path is not used by iPhone or iPad Smart Stacks.

Design Patterns

• Prefer `Gauge` over manual arcs. Use .gaugeStyle(.accessoryCircular) for

Lock Screen circular widgets and .linearCapacity for home screen capacity bars. The system handles styling, accessibility, and rendering-mode adaptation.

• Use `.containerBackground(_:for: .widget)` (iOS 17+) for widget backgrounds

instead of padding and background modifiers.

• Use `Canvas` for dense visualizations like sparklines or mini bar charts.

The lack of per-element accessibility is acceptable since the entire widget surface is a single tap target.

• Match timeline refresh to data granularity. Apple budgets

40–70 refreshes per day with entries at least 5 minutes apart. Use Text(timerInterval:countsDown:) for live countdowns instead of burning timeline entries.

See references/widgetkit-advanced.md for code examples and detailed guidance on each pattern.

iOS 26 Additions

Liquid Glass Support

Adapt widgets to Liquid Glass with @Environment(\.widgetRenderingMode), .widgetAccentable(), and Image.widgetAccentedRenderingMode(_:). In .vibrant, the system maps content into the material style, so avoid relying on original colors alone.

Push Reload Handlers

Widget push reloads:

• Add Push Notifications capability to the widget extension target.
• Keep the WidgetPushHandler type in the widget extension target or shared

code linked into it, not only in the main app target.

• Register the handler with .pushHandler(...) on the widget configuration.
• Do not use User Notifications registration to obtain widget push tokens;

WidgetKit supplies tokens through pushTokenDidChange(_:widgets:).

• Use apns-push-type: widgets, topic suffix .push-type.widgets, and

aps.content-changed.

• Treat push as a budgeted, opportunistic reload signal, not state delivery and

not the only freshness model. Timelines, reload policies, shared storage or refetch, and app-triggered WidgetCenter reloads remain the fallback path.

Control push reloads:

• Register a ControlPushHandler with .pushHandler(...) on the

ControlWidgetConfiguration.

• pushTokensDidChange(controls:) receives [ControlInfo]; read tokens from

each control's pushInfo.

• Use apns-push-type: controls, topic suffix .push-type.controls, and

aps.content-changed.

CarPlay Widgets

Small system widgets can appear in CarPlay on iOS 26+. Ensure layouts are legible at a glance; taps and controls depend on vehicle touch support and, for opening the app, CarPlay integration.

Common Mistakes

1. Using IntentTimelineProvider instead of AppIntentTimelineProvider. IntentTimelineProvider is the older SiriKit Intents-based provider. Prefer AppIntentTimelineProvider with the App Intents framework for new widgets.

2. Exceeding the refresh budget. Widgets have a daily refresh limit. Do not call WidgetCenter.shared.reloadTimelines(ofKind:) on every minor data change. Batch updates and use appropriate TimelineReloadPolicy values.

3. Forgetting App Groups for shared data. The widget extension runs in a separate process. Use UserDefaults(suiteName:) or a shared App Group container for data the widget reads.

4. Performing network calls in placeholder(). placeholder(in:) must return synchronously with sample data. Use getTimeline or timeline(for:in:) for async work.

5. Letting WidgetKit absorb sibling-skill work. Keep full Live Activity lifecycle in activitykit and full App Intent modeling in app-intents.

6. Treating WidgetKit push payloads as state. Widget and control pushes are reload signals. Persist state in shared storage or refetch it in the provider.

7. Registering widget pushes through User Notifications. Widget push tokens come from WidgetKit handlers, not UNUserNotificationCenter.

8. Putting heavy logic in the widget view. Widget views are rendered in a size-limited process. Pre-compute data in the timeline provider and pass display-ready values through the entry.

9. Ignoring accessory rendering modes. Lock Screen widgets render in .vibrant or .accented mode, not .fullColor. Test with @Environment(\.widgetRenderingMode) and avoid relying on color alone.

10. Not testing on device. StandBy, CarPlay, and accessory rendering differ significantly from Simulator. Always verify on physical hardware.

Review Checklist

• [ ] Widget extension target has App Groups entitlement matching the main app
• [ ] @main is on the WidgetBundle, not on individual widgets
• [ ] placeholder(in:) returns synchronously; getSnapshot/snapshot(for:in:) fast when isPreview
• [ ] Timeline reload policy matches update frequency; reloadTimelines(ofKind:) only on data change
• [ ] Layout adapts per WidgetFamily; accessory widgets tested in .vibrant mode
• [ ] Interactive widgets use extension-available App Intents with Button/Toggle only
• [ ] One .widgetURL(_:) fallback is used; Link subtargets are family-appropriate
• [ ] Widget push handlers live in the widget extension/shared code and do not use User Notifications token registration
• [ ] Widget/control pushes supplement timelines and shared-state/refetch fallbacks
• [ ] Smart Stack relevance uses timeline relevance and app-side intent donations where useful
• [ ] Live Activity lifecycle and App Intent modeling are handed off to sibling skills
• [ ] Controls use StaticControlConfiguration/AppIntentControlConfiguration
• [ ] Timeline entries and Intent types are Sendable; tested on device

References

• Advanced guide: references/widgetkit-advanced.md
• Apple docs: WidgetKit | Keeping a widget up to date | Smart Stack visibility

WidgetKit Advanced Reference

This reference is WidgetKit-first. ActivityKit and App Intents details appear only where they affect widget bundles, Live Activity registration, controls, or Smart Stack visibility; use sibling activitykit and app-intents skills for full lifecycle, APNs content-state, Siri/Shortcuts/Spotlight, and entity-query design.

Contents

• Timeline Strategies
• Push-Based Widget and Control Reloads
• Widget URL Handling and Deep Links
• Intent-Driven Widget Configuration
• Multiple Widget Support in WidgetBundle
• Widget Previews and Snapshots
• AccessoryWidgetBackground
• Dynamic Island Expanded Layout Patterns
• Alert Configuration for Live Activities
• Push Notification Support for Live Activities
• ActivityAuthorizationInfo
• Widget Performance Best Practices
• Xcode Setup
• Widget Relevance and Smart Stacks
• ActivityState Lifecycle
• ActivityStyle
• Dismissal Policies
• Querying Active Widgets and Activities
• Design Patterns
• Apple Documentation Links

Timeline Strategies

TimelineReloadPolicy

Control when WidgetKit requests a new timeline after the current entries expire.

Multiple Timeline Entries

Pre-generate entries for known future states to reduce refresh requests and conserve the daily budget.

func timeline(for configuration: Intent, in context: Context) async -> Timeline<StockEntry> {
    var entries: [StockEntry] = []
    let now = Date()

    // Generate hourly entries for the next 6 hours
    for hourOffset in 0..<6 {
        let entryDate = Calendar.current.date(byAdding: .hour, value: hourOffset, to: now)!
        let price = await StockService.shared.projectedPrice(at: entryDate, for: configuration.symbol)
        entries.append(StockEntry(date: entryDate, symbol: configuration.symbol.name, price: price))
    }

    let nextRefresh = Calendar.current.date(byAdding: .hour, value: 6, to: now)!
    return Timeline(entries: entries, policy: .after(nextRefresh))
}

Triggering Manual Reloads

// Reload a specific widget kind
WidgetCenter.shared.reloadTimelines(ofKind: "OrderStatusWidget")

// Reload all widgets
WidgetCenter.shared.reloadAllTimelines()

Call reloadTimelines(ofKind:) only when displayed data actually changes. Each call counts against the daily refresh budget.

Refresh Budget

Each configured widget has a daily refresh limit. Exemptions apply for:

• Foreground app usage
• Active media sessions
• Standard location service usage

WidgetKit does not impose refresh limits when debugging in Xcode.

Push-Based Widget and Control Reloads

WidgetPushHandler

Use WidgetKit push notifications as a budgeted, opportunistic reload signal in addition to normal timelines. Add the Push Notifications capability to the widget extension, implement WidgetPushHandler, and register the handler on the widget configuration with .pushHandler(...).

struct MyWidgetPushHandler: WidgetPushHandler {
    func pushTokenDidChange(_ pushInfo: WidgetPushInfo, widgets: [WidgetInfo]) {
        let tokenString = pushInfo.token.map { String(format: "%02x", $0) }.joined()
        Task {
            try await ServerAPI.shared.register(widgetPushToken: tokenString)
        }
    }
}

struct CaffeineTrackerWidget: Widget {
    var body: some WidgetConfiguration {
        StaticConfiguration(kind: "CaffeineTracker", provider: Provider()) { entry in
            CaffeineTrackerView(entry: entry)
        }
        .configurationDisplayName("Caffeine Tracker")
        .pushHandler(MyWidgetPushHandler.self)
    }
}

Server-Side Integration

Send an APNs push with the widget's push token. The system calls your TimelineProvider.getTimeline or AppIntentTimelineProvider.timeline(for:in:) when the push arrives. Use apns-push-type: widgets, an apns-topic of <bundleID>.push-type.widgets, and an aps payload with "content-changed": true. WidgetKit push notifications cannot use broadcast channels. Treat this as a reload signal; keep durable state in shared storage or refetch it when the provider runs.

ControlPushHandler

Controls use their own push handler and APNs push type. Register the handler on the ControlWidgetConfiguration with .pushHandler(...).

struct GarageDoorControl: ControlWidget {
    var body: some ControlWidgetConfiguration {
        StaticControlConfiguration(kind: "GarageDoor") {
            ControlWidgetButton(action: OpenGarageDoorIntent()) {
                Label("Garage", systemImage: "door.garage.open")
            }
        }
        .pushHandler(MyControlPushHandler.self)
    }
}

struct MyControlPushHandler: ControlPushHandler {
    func pushTokensDidChange(controls: [ControlInfo]) {
        for control in controls {
            guard let token = control.pushInfo?.token else { continue }
            let tokenString = token.map { String(format: "%02x", $0) }.joined()
            Task {
                try await ServerAPI.shared.register(controlPushToken: tokenString)
            }
        }
    }
}

For remote control reloads, use apns-push-type: controls, an apns-topic of <bundleID>.push-type.controls, and an aps payload with "content-changed": true. Do not encode the control's new state as a custom payload key and expect WidgetKit to apply it; update shared state through the app, server, or control action, then let the value provider read it.

For ControlWidgetToggle, the action must conform to SetValueIntent with a Boolean value. The system fills value with the new toggle state.

struct ToggleFlashlightIntent: SetValueIntent {
    static var title: LocalizedStringResource = "Toggle Flashlight"

    @Parameter(title: "On")
    var value: Bool

    func perform() async throws -> some IntentResult {
        try await FlashlightController.shared.setEnabled(value)
        return .result()
    }
}

Widget URL Handling and Deep Links

widgetURL(_:)

Set a single URL for the entire widget. Tapping anywhere opens the app with this URL.

struct SmallWidgetView: View {
    let entry: OrderEntry

    var body: some View {
        VStack {
            Text(entry.orderName)
            Text(entry.status)
        }
        .widgetURL(URL(string: "myapp://orders/\(entry.orderID)")!)
    }
}

Link (Multiple Targets)

Use Link for multiple tap targets in .accessoryRectangular, .systemSmall, and larger system widgets. You can combine one widgetURL(_:) for the general surface with Link controls for specific subregions.

struct MediumWidgetView: View {
    let entry: OrderListEntry

    var body: some View {
        VStack {
            ForEach(entry.orders) { order in
                Link(destination: URL(string: "myapp://orders/\(order.id)")!) {
                    HStack {
                        Text(order.name)
                        Spacer()
                        Text(order.status)
                    }
                }
            }
        }
    }
}

Handling in the App

@main
struct MyApp: App {
    var body: some Scene {
        WindowGroup {
            ContentView()
                .onOpenURL { url in
                    DeepLinkRouter.shared.handle(url)
                }
        }
    }
}

Important: If the view hierarchy includes more than one widgetURL(_:), the behavior is undefined. Use Link for additional targets.

Intent-Driven Widget Configuration

WidgetKit uses WidgetConfigurationIntent as the configuration type for AppIntentConfiguration and AppIntentTimelineProvider. Keep the intent type available to the widget extension or a shared framework linked into it. Design of AppEntity, EntityQuery, Siri, Shortcuts, Spotlight, and parameter resolution belongs in the sibling app-intents skill.

WidgetKit integration points to review here:

• AppIntentConfiguration(kind:intent:provider:content:) uses the intent type.
• AppIntentTimelineProvider receives that intent in snapshot and timeline.
• recommendations() may return AppIntentRecommendation values for the

widget gallery.

Do not expand this section into full intent/entity examples; route that work to app-intents.

Multiple Widget Support in WidgetBundle

Declaring Multiple Widgets

@main
struct MyAppWidgets: WidgetBundle {
    var body: some Widget {
        OrderStatusWidget()          // Home Screen widget
        FavoritesWidget()            // Configurable widget
        StepsAccessoryWidget()       // Lock Screen widget
        DeliveryActivityWidget()     // Live Activity
        QuickActionControl()         // Control Center
    }
}

Conditional Widgets

Include widgets conditionally based on platform or availability:

@main
struct MyAppWidgets: WidgetBundle {
    var body: some Widget {
        CoreWidget()
        if #available(iOS 18, *) {
            QuickActionControl()
        }
    }
}

Widget Previews and Snapshots

Xcode Previews

#Preview("Small", as: .systemSmall) {
    OrderStatusWidget()
} timeline: {
    OrderEntry(date: .now, orderName: "Pizza", status: "Preparing")
    OrderEntry(date: .now.addingTimeInterval(600), orderName: "Pizza", status: "Delivering")
}

#Preview("Circular", as: .accessoryCircular) {
    StepsAccessoryWidget()
} timeline: {
    StepsEntry(date: .now, stepCount: 4200)
}

Live Activity Previews

#Preview("Lock Screen", as: .content, using: DeliveryAttributes.preview) {
    DeliveryActivityWidget()
} contentStates: {
    DeliveryAttributes.ContentState(
        driverName: "Alex",
        estimatedDeliveryTime: Date()...Date().addingTimeInterval(900),
        currentStep: .delivering
    )
}

#Preview("Dynamic Island Compact", as: .dynamicIsland(.compact), using: DeliveryAttributes.preview) {
    DeliveryActivityWidget()
} contentStates: {
    DeliveryAttributes.ContentState(
        driverName: "Alex",
        estimatedDeliveryTime: Date()...Date().addingTimeInterval(900),
        currentStep: .delivering
    )
}

Snapshot Best Practices

• Return sample data immediately in placeholder(in:) -- it must be synchronous.
• In getSnapshot / snapshot(for:in:), check context.isPreview:
• When true, return representative sample data quickly.
• When false, return the current real state.

// WRONG: Performing a network call in placeholder
func placeholder(in context: Context) -> MyEntry {
    // Compilation error: placeholder must be synchronous
    let data = await fetchData()
    return MyEntry(date: .now, data: data)
}

// CORRECT: Return static sample data
func placeholder(in context: Context) -> MyEntry {
    MyEntry(date: .now, data: SampleData.placeholder)
}

AccessoryWidgetBackground

Provide the standard translucent background for Lock Screen widgets.

struct CircularStepsView: View {
    let steps: Int

    var body: some View {
        ZStack {
            AccessoryWidgetBackground()
            VStack(spacing: 2) {
                Image(systemName: "figure.walk")
                    .font(.caption)
                Text("\(steps)")
                    .font(.headline)
                    .widgetAccentable()
            }
        }
    }
}

Rendering Mode Awareness

Lock Screen widgets render in .vibrant or .accented mode. Adapt content:

@Environment(\.widgetRenderingMode) var renderingMode

var body: some View {
    switch renderingMode {
    case .fullColor:
        ColorfulView()
    case .vibrant, .accented:
        MonochromeView()
    @unknown default:
        MonochromeView()
    }
}

Use .widgetAccentable() to mark views that should receive the accent tint in .accented rendering mode.

For images that need special treatment in accented mode, use Image.widgetAccentedRenderingMode(_:). Reserve .fullColor for content such as album art or book covers where preserving the original image matters.

Image("album-art")
    .resizable()
    .widgetAccentedRenderingMode(.fullColor)

Dynamic Island Expanded Layout Patterns

Full Layout Example

DynamicIsland {
    DynamicIslandExpandedRegion(.leading) {
        VStack(alignment: .leading) {
            Image(systemName: "airplane")
                .font(.title2)
            Text("UA 1234")
                .font(.caption2)
        }
    }
    DynamicIslandExpandedRegion(.trailing) {
        VStack(alignment: .trailing) {
            Text("SFO")
                .font(.title3.bold())
            Text("On Time")
                .font(.caption2)
                .foregroundStyle(.green)
        }
    }
    DynamicIslandExpandedRegion(.center) {
        Text("San Francisco to New York")
            .font(.caption)
            .lineLimit(1)
    }
    DynamicIslandExpandedRegion(.bottom) {
        ProgressView(value: 0.45)
            .tint(.blue)
        HStack {
            Text("Departed 2:30 PM")
            Spacer()
            Text("Arrives 10:45 PM")
        }
        .font(.caption2)
        .foregroundStyle(.secondary)
    }
} compactLeading: {
    Image(systemName: "airplane")
} compactTrailing: {
    Text("2h 15m")
        .monospacedDigit()
} minimal: {
    Image(systemName: "airplane")
}

Vertical Placement

Control vertical alignment within expanded regions:

DynamicIslandExpandedRegion(.leading) {
    Text("Top")
        .dynamicIsland(verticalPlacement: .belowIfTooWide)
}

Content Margins

Override margins for specific Dynamic Island modes:

.contentMargins(.trailing, 20, for: .expanded)
.contentMargins(.bottom, 16, for: .expanded)

Keyline Tint

Apply a subtle tint to the Dynamic Island border:

DynamicIsland { /* ... */ }
    .keylineTint(.blue)

Alert Configuration for Live Activities

Trigger a visible and audible alert when updating a Live Activity:

let alert = AlertConfiguration(
    title: "Delivery Update",
    body: "Your order is out for delivery!",
    sound: .default
)
await activity.update(updatedContent, alertConfiguration: alert)

Custom Alert Sound

let alert = AlertConfiguration(
    title: "Score Update",
    body: "Goal! The score is now 2-1.",
    sound: .named("goal-horn.aiff")
)

Place the sound file in the app bundle. Use .default when no custom sound is needed.

Push Notification Support for Live Activities

Registering for Push Updates

let activity = try Activity.request(
    attributes: attributes,
    content: content,
    pushType: .token  // Enable push updates
)

// Observe token changes
Task {
    for await token in activity.pushTokenUpdates {
        let tokenString = token.map { String(format: "%02x", $0) }.joined()
        try await ServerAPI.shared.registerActivityToken(tokenString, activityID: activity.id)
    }
}

Push-to-Start (Remote Activity Creation)

// Observe the push-to-start token
Task {
    for await token in Activity<DeliveryAttributes>.pushToStartTokenUpdates {
        let tokenString = token.map { String(format: "%02x", $0) }.joined()
        try await ServerAPI.shared.registerPushToStartToken(tokenString)
    }
}

Channel-Based ActivityKit Push (iOS 18+)

ActivityKit broadcast channels are for Live Activity updates, not WidgetKit timeline push notifications. Pass a valid base64-encoded channel ID that your server created through APNs channel management.

let channelID = "ZGVsaXZlcnktdXBkYXRlcw=="
let activity = try Activity.request(
    attributes: attributes,
    content: content,
    pushType: .channel(channelID)
)

APNs Payload Format for Live Activity Updates

{
    "aps": {
        "timestamp": 1234567890,
        "event": "update",
        "content-state": {
            "driverName": "Alex",
            "estimatedDeliveryTime": {
                "lowerBound": 1234567890,
                "upperBound": 1234568790
            },
            "currentStep": "delivering"
        },
        "alert": {
            "title": "Delivery Update",
            "body": "Your driver is nearby!"
        }
    }
}

The content-state must match the ContentState Codable structure exactly.

Info.plist Keys

ActivityAuthorizationInfo

Check whether Live Activities are permitted before attempting to start one.

let authInfo = ActivityAuthorizationInfo()

// Check permission synchronously
if authInfo.areActivitiesEnabled {
    try Activity.request(attributes: attributes, content: content, pushType: .token)
}

// Observe permission changes
Task {
    for await enabled in authInfo.activityEnablementUpdates {
        if enabled {
            // Activities became available
        }
    }
}

// Check frequent push support
if authInfo.frequentPushesEnabled {
    // Safe to use frequent push updates
}

Error Handling

do {
    let activity = try Activity.request(attributes: attributes, content: content, pushType: .token)
} catch let error as ActivityAuthorizationError {
    switch error {
    case .denied:
        // User disabled Live Activities in Settings
        break
    case .globalMaximumExceeded:
        // Too many Live Activities across all apps
        break
    case .targetMaximumExceeded:
        // Too many Live Activities for this app
        break
    default:
        break
    }
}

Widget Performance Best Practices

Data Preparation

Pre-compute display values in the timeline provider. Pass display-ready data through the entry.

// WRONG: Heavy computation in the widget view
struct MyWidgetView: View {
    let entry: RawDataEntry

    var body: some View {
        let processed = HeavyProcessor.process(entry.rawData)  // Slow
        Text(processed.summary)
    }
}

// CORRECT: Pre-compute in the provider
func timeline(for configuration: Intent, in context: Context) async -> Timeline<ProcessedEntry> {
    let raw = await DataStore.shared.fetch()
    let processed = HeavyProcessor.process(raw)
    let entry = ProcessedEntry(date: .now, summary: processed.summary, value: processed.value)
    return Timeline(entries: [entry], policy: .atEnd)
}

Memory Constraints

Widget extensions run with strict memory limits. Avoid:

• Loading large images directly in the widget view
• Storing large data sets in the entry
• Creating complex view hierarchies

Image Handling

// WRONG: Loading a full-resolution image
Image(uiImage: UIImage(contentsOfFile: fullResPath)!)

// CORRECT: Use a pre-resized thumbnail stored in the shared container
Image(uiImage: UIImage(contentsOfFile: thumbnailPath)!)
    .resizable()
    .aspectRatio(contentMode: .fill)

Shared Data with App Groups

// In the main app: write data
let defaults = UserDefaults(suiteName: "group.com.example.myapp")
defaults?.set(encodedData, forKey: "widgetData")
WidgetCenter.shared.reloadTimelines(ofKind: "MyWidget")

// In the widget provider: read data
func timeline(for configuration: Intent, in context: Context) async -> Timeline<MyEntry> {
    let defaults = UserDefaults(suiteName: "group.com.example.myapp")
    let data = defaults?.data(forKey: "widgetData")
    // Decode and build entry
}

For larger datasets, use a shared SQLite database or Core Data store in the App Group container.

Xcode Setup

Adding a Widget Extension Target

1. File > New > Target > Widget Extension. 2. Name the extension (e.g., "MyAppWidgets"). 3. Select "Include Configuration App Intent" for configurable widgets. 4. Select "Include Live Activity" if building Live Activities.

Entitlements

App Groups Configuration

1. Enable "App Groups" capability on both the main app target and the widget extension target. 2. Create a shared group identifier (e.g., group.com.example.myapp). 3. Use UserDefaults(suiteName:) or FileManager.containerURL(forSecurityApplicationGroupIdentifier:) for shared storage.

Build Schemes

• Use the widget extension scheme to debug widget rendering.
• Select "Widget" as the run destination to launch the widget directly.
• Use "Preview" in Xcode canvas for rapid iteration.

Common Xcode Issues

// ERROR: "Widget extension must include at least one widget"
// FIX: Ensure @main is on the WidgetBundle, not a widget struct.

// ERROR: "No such module 'WidgetKit'"
// FIX: Ensure the widget extension target links WidgetKit and SwiftUI frameworks.

// ERROR: "The operation couldn't be completed. (ActivityKit.ActivityAuthorizationError error 3.)"
// FIX: Add NSSupportsLiveActivities = YES to the HOST APP's Info.plist (not the extension).

Widget Relevance and Smart Stacks

TimelineEntryRelevance

Score entries to surface widgets in Smart Stacks when relevant:

struct GameEntry: TimelineEntry {
    var date: Date
    var score: String
    var isLive: Bool

    var relevance: TimelineEntryRelevance? {
        isLive ? TimelineEntryRelevance(score: 100, duration: 3600) : nil
    }
}

Higher scores make the widget more likely to surface. The duration specifies how long the relevance lasts.

WidgetRelevance (AppIntentTimelineProvider)

On iPhone and iPad, prefer TimelineEntryRelevance on timeline entries and donate App Intents that match configurable widget parameters. Smart Stacks on iPhone and iPad don't use the timeline provider's relevance() callback.

On watchOS, use relevance() only when providing RelevanceKit contextual clues. Return WidgetRelevance([WidgetRelevanceAttribute(...)]); there is no WidgetRelevance(intent, score:) initializer.

ActivityState Lifecycle

Track the full lifecycle of a Live Activity:

Task {
    for await state in activity.activityStateUpdates {
        switch state {
        case .active:
            // Activity is running and visible
            break
        case .pending:
            // Requested but not yet displayed (iOS 26+)
            break
        case .stale:
            // Content is outdated; update or end
            break
        case .ended:
            // Ended but may still be visible on Lock Screen
            break
        case .dismissed:
            // Fully removed from UI; clean up resources
            break
        @unknown default:
            break
        }
    }
}

ActivityStyle

Control Live Activity persistence behavior (iOS 18+):

// Standard: persists until explicitly ended
let activity = try Activity.request(
    attributes: attributes,
    content: content,
    pushType: .token,
    style: .standard
)

// Transient: appears in Dynamic Island's extended presentation and ends
// automatically when the user leaves that interaction context.
let activity = try Activity.request(
    attributes: attributes,
    content: content,
    pushType: .token,
    style: .transient
)

Use .transient for short interactions that should not persist as a standard Live Activity after the user locks the device, collapses the Dynamic Island, leaves the app, or performs other tasks outside the Dynamic Island.

Dismissal Policies

Control when an ended Live Activity disappears from the Lock Screen:

// System-determined timing (default)
await activity.end(finalContent, dismissalPolicy: .default)

// Remove immediately
await activity.end(finalContent, dismissalPolicy: .immediate)

// Remove after a specific date (max 4 hours)
let removalDate = Date().addingTimeInterval(3600)
await activity.end(finalContent, dismissalPolicy: .after(removalDate))

Querying Active Widgets and Activities

Current Widget Configurations

let widgets = try await WidgetCenter.shared.currentConfigurations()
for widget in widgets {
    print("Kind: \(widget.kind), Family: \(widget.family)")
}

Current Live Activities

let activities = Activity<DeliveryAttributes>.activities
for activity in activities {
    print("ID: \(activity.id), State: \(activity.activityState)")
}

Observing New Activities

Task {
    for await activity in Activity<DeliveryAttributes>.activityUpdates {
        print("New activity started: \(activity.id)")
    }
}

Design Patterns

Prefer Gauge for Value Indicators

Use Gauge (iOS 16+) instead of manual Circle or Path arcs to show a value within a range. The system handles styling, accessibility, and rendering-mode adaptation automatically.

• .accessoryCircular — open ring with center value label, matches the system

complication style. Use for accessoryCircular Lock Screen widgets.

• .linearCapacity — horizontal bar that fills leading to trailing. Use for

home screen widgets when a capacity bar fits.

// accessoryCircular Lock Screen widget
struct StepsCircularView: View {
    let entry: StepsEntry

    var body: some View {
        Gauge(value: Double(entry.stepCount), in: 0...10000) {
            Image(systemName: "figure.walk")
        } currentValueLabel: {
            Text("\(entry.stepCount)")
        }
        .gaugeStyle(.accessoryCircular)
    }
}

// Home screen capacity bar
Gauge(value: storageUsed, in: 0...storageTotal) {
    Text("Storage")
} currentValueLabel: {
    Text(storageUsed, format: .byteCount(style: .file))
}
.gaugeStyle(.linearCapacity)

Use containerBackground for Widget Backgrounds

.containerBackground(_:for: .widget) (iOS 17+) is the designated way to set widget backgrounds. Replaces older padding and background patterns. The system uses this placement to correctly render backgrounds across all widget surfaces.

struct OrderWidgetView: View {
    let entry: OrderEntry

    var body: some View {
        VStack(alignment: .leading) {
            Text(entry.orderName).font(.headline)
            Text(entry.status).foregroundStyle(.secondary)
        }
        .containerBackground(.fill.tertiary, for: .widget)
    }
}

Use Canvas for Dense Visualizations

Use Canvas for sparklines, mini bar charts, or heat maps inside widgets. The lack of per-element accessibility is acceptable since the entire widget surface is a single tap target.

struct SparklineView: View {
    let values: [Double]

    var body: some View {
        Canvas { context, size in
            guard values.count > 1 else { return }
            let maxVal = values.max() ?? 1
            let step = size.width / CGFloat(values.count - 1)
            var path = Path()
            for (i, value) in values.enumerated() {
                let x = step * CGFloat(i)
                let y = size.height * (1 - value / maxVal)
                if i == 0 { path.move(to: CGPoint(x: x, y: y)) }
                else { path.addLine(to: CGPoint(x: x, y: y)) }
            }
            context.stroke(path, with: .color(.blue), lineWidth: 2)
        }
    }
}

Match Timeline Refresh to Data Granularity

Apple budgets 40–70 refreshes per day for frequently viewed widgets, with entries at least 5 minutes apart. Align reload cadence to how often the underlying data actually changes.

• Generate entries for as many future dates as possible to reduce reload requests.
• Use .after(date) when data updates on a known schedule (market hours, transit).
• Use .never when data only changes from user action.
• Use Text(timerInterval:countsDown:) for live countdowns instead of burning

timeline entries on every tick.

Apple Documentation Links

• WidgetKit
• ActivityKit
• TimelineProvider
• AppIntentTimelineProvider
• ActivityAttributes
• ActivityConfiguration
• DynamicIsland
• ControlWidgetButton
• ControlWidgetToggle
• Keeping a widget up to date
• Updating widgets with WidgetKit push notifications
• Updating controls locally and remotely
• Linking to specific app scenes
• Adding StandBy and CarPlay support
• Optimizing for accented rendering and Liquid Glass
• Increasing widget visibility in Smart Stacks