app-intent-driven-development（应用意图驱动开发）

App Intent–First Driven Development

Design features as App Intents first, then reuse those intents across Shortcuts, widgets, and SwiftUI views so automation and UI stay in lockstep.

Core Ideas

• Entities first: model the data users act on (events, categories, records) as AppEntity so intents, widgets, and the app share one source of truth.
• Intent-first feature: build the App Intent + entity query before UI; SwiftUI screens call those intents instead of duplicating service code.
• Single action, single intent: keep intents focused; avoid mega-intents that are hard to compose in Shortcuts.
• Predictable UI: supply DisplayRepresentation, typeDisplayRepresentation, and icons so Siri/Shortcuts can render rich cards without opening the app.
• Fast queries: EntityQuery must be quick and cancellable; avoid blocking the main actor.
• Reuse business logic: intents call the same services your views use; do not fork logic inside the intent.

Minimal Entity Blueprint

import AppIntents

struct TaskEntity: AppEntity, Identifiable {
    static let typeDisplayRepresentation = TypeDisplayRepresentation(name: "Task")
    static let defaultQuery = TaskQuery()

    let id: UUID
    let title: String
    let isComplete: Bool

    var displayRepresentation: DisplayRepresentation {
        DisplayRepresentation(
            title: title,
            subtitle: isComplete ? "Completed" : "Open",
            image: .init(systemName: isComplete ? "checkmark.circle.fill" : "circle")
        )
    }
}

struct TaskQuery: EntityQuery {
    func entities(for identifiers: [UUID]) async throws -> [TaskEntity] {
        try await TaskStore.shared.fetch(ids: identifiers) // fast path
    }

    func suggestedEntities() async throws -> [TaskEntity] {
        try await TaskStore.shared.fetchRecent()
    }
}

Key points: stable identifier, meaningful representation, and fast queries that avoid launching heavy app flows.

Intent Pattern

import AppIntents

struct CompleteTaskIntent: AppIntent {
    static let title: LocalizedStringResource = "Complete Task"
    static let description = IntentDescription("Marks a task as done and returns the updated item.")

    @Parameter(title: "Task", requestValueDialog: "Which task should I complete?")
    var task: TaskEntity

    // Used so we can call the intent from SwiftUI using .perform()
    init(task: TaskEntity) { self.task = task }

    @MainActor
    func perform() async throws -> some IntentResult & ReturnsValue<TaskEntity> {
        let updated = try await TaskStore.shared.complete(task.id)
        return .result(value: updated)
    }

    static var parameterSummary: some ParameterSummary {
        Summary("Complete \(\.$task)")
    }
}

• Parameters: keep them few; provide requestValueDialog to make Siri prompts natural.
• Results: return entities when possible; system surfaces render them nicely.
• Isolation: mark with @MainActor only if you must touch UI-bound objects; otherwise keep work off the main actor.

Reusing Intents in SwiftUI

• Prefer calling intents from UI so automation and in-app flows share one path.
• Use AppIntentButton to invoke intents directly from views.
• Translate entity selections into view state so widgets/Shortcuts and in-app pickers present the same objects.

import AppIntents
import SwiftUI

struct EventRow: View {
    let event: EventEntity

    var body: some View {
        HStack {
            Text(event.name)
            Spacer()
            AppIntentButton(intent: UndoLastEventOccuranceIntent(event: event)) {
                Label("Undo", systemImage: "arrow.uturn.backward")
            }
        }
    }
}

• For more control, invoke intents imperatively with perform (e.g., to show progress or handle errors):

import AppIntents
import SwiftUI

struct EventRow: View {
    @Environment(\.intentExecutor) private var executor
    @State private var isWorking = false
    @State private var error: Error?

    let event: EventEntity

    var body: some View {
        HStack {
            Text(event.name)
            Spacer()
            Button {
                Task {
                    isWorking = true
                    defer { isWorking = false }
                    do {
                        try await executor.perform(UndoLastEventOccuranceIntent(event: event))
                    } catch {
                        self.error = error
                    }
                }
            } label: {
                if isWorking {
                    ProgressView()
                } else {
                    Label("Undo", systemImage: "arrow.uturn.backward")
                }
            }
        }
        .alert("Undo failed", isPresented: .init(
            get: { error != nil },
            set: { if !$0 { error = nil } }
        )) {
            Button("OK", role: .cancel) { error = nil }
        } message: {
            Text(error?.localizedDescription ?? "Unknown error")
        }
    }
}

• Keep the intent signature identical between Shortcuts and SwiftUI usage.
• Avoid reimplementing service calls in views; route through the intent to keep analytics, validation, and side effects consistent.

Development Flow

1. Model the domain type as AppEntity with DisplayRepresentation and EntityQuery.
2. Implement a focused AppIntent that calls shared services; avoid duplicate data access layers inside the intent.
3. Add previews in Shortcuts or the App Intents preview panel; ensure suggested entities show immediately.
4. Expose the same entity in widgets/Live Activities to keep automation and UI consistent.
5. Localize strings early (LocalizedStringResource) to keep Siri responses natural in all supported languages.

Quick Checklist

• Entity has stable id, typeDisplayRepresentation, and rich displayRepresentation.
• Queries are fast, cancellable, and return suggestions without opening the app.
• Intent reuses shared domain services; no duplicated business logic.
• Parameters are minimal and well phrased with requestValueDialog.
• Results return entities when possible for better system rendering.
• Strings are localized; tests cover queries and perform paths.