swiftui-webkit

SKILL.md

SwiftUI WebKit

Embed and manage web content in SwiftUI using the native WebKit-for-SwiftUI APIs introduced for iOS 26, iPadOS 26, macOS 26, and visionOS 26. Use this skill when the app needs an integrated web surface, app-owned HTML content, JavaScript-backed page interaction, or custom navigation policy control.

Contents

Choose the Right Web Container

Use the narrowest tool that matches the job.

Need Default choice
Embedded app-owned web content in SwiftUI WebView + WebPage
Simple external site presentation with Safari behavior SFSafariViewController
OAuth or third-party sign-in ASWebAuthenticationSession
Back-deploy below iOS 26 or use missing legacy-only WebKit features WKWebView fallback

Prefer WebView and WebPage for modern SwiftUI apps targeting iOS 26+. Apple’s WWDC25 guidance explicitly recommends migrating SwiftUI apps away from UIKit/AppKit WebKit wrappers when possible.

Do not use embedded web views for OAuth. That stays an ASWebAuthenticationSession flow.

Displaying Web Content

Use the simple WebView(url:) form when the app only needs to render a URL and SwiftUI state drives navigation.

import SwiftUI
import WebKit

struct ArticleView: View {
    let url: URL

    var body: some View {
        WebView(url: url)
    }
}

Create a WebPage when the app needs to load requests directly, observe state, call JavaScript, or customize navigation behavior.

@Observable
@MainActor
final class ArticleModel {
    let page = WebPage()

    func load(_ url: URL) async throws {
        for try await _ in page.load(URLRequest(url: url)) {
        }
    }
}

struct ArticleDetailView: View {
    @State private var model = ArticleModel()
    let url: URL

    var body: some View {
        WebView(model.page)
            .task {
                try? await model.load(url)
            }
    }
}

See references/loading-and-observation.md for full examples.

Loading and Observing with WebPage

WebPage is an @MainActor observable type. Use it when you need page state in SwiftUI.

Common loading entry points:

  • load(URLRequest)
  • load(URL)
  • load(html:baseURL:)
  • load(_:mimeType:characterEncoding:baseURL:)

Common observable properties:

  • title
  • url
  • isLoading
  • estimatedProgress
  • currentNavigationEvent
  • backForwardList
struct ReaderView: View {
    @State private var page = WebPage()

    var body: some View {
        WebView(page)
            .navigationTitle(page.title ?? "Loading")
            .overlay {
                if page.isLoading {
                    ProgressView(value: page.estimatedProgress)
                }
            }
            .task {
                do {
                    for try await _ in page.load(URLRequest(url: URL(string: "https://example.com")!)) {
                    }
                } catch {
                    // Handle load failure.
                }
            }
    }
}

When you need to react to every navigation, observe the navigation sequence rather than only checking a single property.

Task {
    for await event in page.navigations {
        // Handle finish, redirect, or failure events.
    }
}

See references/loading-and-observation.md for stronger patterns and the load-sequence examples.

Navigation Policies

Use WebPage.NavigationDeciding to allow, cancel, or customize navigations based on the request or response.

Typical uses:

  • keep app-owned domains inside the embedded web view
  • cancel external domains and hand them off with openURL
  • intercept special callback URLs
  • tune NavigationPreferences
@MainActor
final class ArticleNavigationDecider: WebPage.NavigationDeciding {
    var urlToOpenExternally: URL?

    func decidePolicy(
        for action: WebPage.NavigationAction,
        preferences: inout WebPage.NavigationPreferences
    ) async -> WKNavigationActionPolicy {
        guard let url = action.request.url else { return .allow }

        if url.host == "example.com" {
            return .allow
        }

        urlToOpenExternally = url
        return .cancel
    }
}

Keep app-level deep-link routing in the navigation skill. This skill owns navigation that happens inside embedded web content.

See references/navigation-and-javascript.md for complete patterns.

JavaScript Integration

Use callJavaScript(_:arguments:in:contentWorld:) to evaluate JavaScript functions against the page.

let script = """
const headings = [...document.querySelectorAll('h1, h2')];
return headings.map(node => ({
    id: node.id,
    text: node.textContent?.trim()
}));
"""

let result = try await page.callJavaScript(script)
let headings = result as? [[String: Any]] ?? []

You can pass values through the arguments dictionary and cast the returned Any into the Swift type you actually need.

let result = try await page.callJavaScript(
    "return document.getElementById(sectionID)?.getBoundingClientRect().top ?? null;",
    arguments: ["sectionID": selectedSectionID]
)

Important boundary: the native SwiftUI WebKit API clearly supports Swift-to-JavaScript calls, but it does not expose an obvious direct replacement for WKScriptMessageHandler. If you need coarse JS-to-native signaling, a custom navigation or callback-URL pattern can work, but document it as a workaround pattern, not a guaranteed one-to-one replacement.

See references/navigation-and-javascript.md.

Local Content and Custom URL Schemes

Use WebPage.Configuration and URLSchemeHandler when the app needs bundled HTML, offline documents, or app-provided resources under a custom scheme.

var configuration = WebPage.Configuration()
configuration.urlSchemeHandlers[URLScheme("docs")!] = DocsSchemeHandler(bundle: .main)

let page = WebPage(configuration: configuration)
for try await _ in page.load(URL(string: "docs://article/welcome")!) {
}

Use this for:

  • bundled documentation or article content
  • offline HTML/CSS/JS assets
  • app-owned resource loading under a custom scheme

Do not overuse custom schemes for normal remote content. Prefer standard HTTPS for server-hosted pages.

See references/local-content-and-custom-schemes.md.

WebView Customization

Use WebView modifiers to match the intended browsing experience.

Useful modifiers and related APIs:

  • webViewBackForwardNavigationGestures(_:)
  • findNavigator(isPresented:)
  • webViewScrollPosition(_:)
  • webViewOnScrollGeometryChange(...)

Apply them only when the user experience needs them.

  • Enable back/forward gestures when people are likely to visit multiple pages.
  • Add Find in Page when the content is document-like.
  • Sync scroll position only when the app has a sidebar, table of contents, or other explicit navigation affordance.

Apple’s HIG also applies here: support back/forward navigation when appropriate, but do not turn an app web view into a general-purpose browser.

Common Mistakes

  • Using WKWebView wrappers by default in an iOS 26+ SwiftUI app instead of starting with WebView and WebPage
  • Using embedded web views for OAuth instead of ASWebAuthenticationSession
  • Reaching for WebPage only after building a plain WebView(url:) path that now needs state, JS, or navigation control
  • Treating callJavaScript as a direct replacement for WKScriptMessageHandler
  • Keeping all links inside the app when external domains should open outside the embedded surface
  • Building a browser-style app shell around WebView instead of a focused embedded experience
  • Using custom URL schemes for content that should just load over HTTPS
  • Forgetting that WebPage is main-actor-isolated

Review Checklist

  • WebView and WebPage are the default path for iOS 26+ SwiftUI web content
  • ASWebAuthenticationSession is used for auth flows instead of embedded web views
  • WebPage is used whenever the app needs state observation, JS calls, or policy control
  • Navigation policies only intercept the URLs the app actually owns or needs to reroute
  • External domains open externally when appropriate
  • JavaScript return values are cast defensively to concrete Swift types
  • Custom URL schemes are used only for real app-owned resources
  • Back/forward gestures or controls are enabled when multi-page browsing is expected
  • The web experience adds focused native value instead of behaving like a thin browser shell
  • Fallback to WKWebView is justified by deployment target or missing API needs

References

Weekly Installs
119
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313
First Seen
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Installed on
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