iOS 18中Action Extension无法打开主应用，原方法失效求助

问题背景 #

开发带有Action Extension的iOS应用，此前在iOS 17及更早版本中，从扩展通过URL Scheme打开主应用的功能正常运行，但在iOS 18中完全失效，导致恢复流程无法启动。

此前的实现方案（iOS 17及以前可用） #

动作视图控制器中的原始实现 #

private func restore() {
    let publicURL = String(kUTTypeURL)
    let publicText = String(kUTTypeText)

    let extensionItem: NSExtensionItem = extensionContext?.inputItems.first as! NSExtensionItem
    let itemProvider = extensionItem.attachments?.first as! NSItemProvider
    if itemProvider.hasItemConformingToTypeIdentifier(publicURL) {
        itemProvider.loadItem(forTypeIdentifier: publicURL, options: nil, completionHandler: { [weak self] item, _ in
            if let fileURL: NSURL = item as? NSURL,
               let tmpURL = VPRealmManager.restore(url: fileURL as URL)
            {
                let sharedDefaults = UserDefaults(suiteName: Key.AppGroup.Identifier)!
                sharedDefaults.set(tmpURL.absoluteString, forKey: "backup_file_key")
                sharedDefaults.synchronize()
                self?.openVoicepaperApp(path: "restore")
            }
        })
    }

    closeExtension()
}

func openVoicepaperApp(path: String = "") {
    let url = NSURL(string: "voicepaper2://" + path)
    let selectorOpenURL = sel_registerName("openURL:")
    let context = NSExtensionContext()
    context.open(url! as URL, completionHandler: nil)

    var responder = self as UIResponder?
    while responder != nil {
        if responder?.responds(to: selectorOpenURL) == true {
            responder?.perform(selectorOpenURL, with: url)
        }
        responder = responder!.next
    }
}

简化实现方案 #

func openVoicepaperApp(path: String = "") {
    if let url = URL(string: "voicepaper2://" + path) {
        extensionContext?.open(url, completionHandler: nil)
    }
}

主应用中的URL处理代码（AppDelegate.swift） #

func application(_ app: UIApplication, open url: URL, options: [UIApplication.OpenURLOptionsKey: Any] = [:]) -> Bool {
    // ... 其他URL处理逻辑 ...

    let DefaultsForAppGroup = UserDefaults(suiteName: Key.AppGroup.Identifier)!
    if url.absoluteString.contains("restore"), let fileUrl = DefaultsForAppGroup.object(forKey: "backup_file_key") as? String,
       let backupFileURL = URL(string: fileUrl)
    {
        // 展示弹窗并执行恢复操作
    }

    return true
}

问题核心 #

上述两种openVoicepaperApp实现方式，在iOS 18中均无法触发主应用的启动，导致恢复流程中断。

排查与解决方案建议 #

1. 修正扩展上下文的生命周期问题 #

原代码中restore()方法在异步加载ItemProvider的同时，同步调用了closeExtension()，可能导致extensionContext在open方法执行前就被销毁。iOS 18对扩展的生命周期管理更严格，需将closeExtension()移到异步回调或open方法的完成回调中：

// 修改后的restore方法
private func restore() {
    let publicURL = String(kUTTypeURL)
    let extensionItem = extensionContext?.inputItems.first as! NSExtensionItem
    let itemProvider = extensionItem.attachments?.first as! NSItemProvider
    
    if itemProvider.hasItemConformingToTypeIdentifier(publicURL) {
        itemProvider.loadItem(forTypeIdentifier: publicURL, options: nil) { [weak self] item, error in
            guard let self = self, let fileURL = item as? URL, let tmpURL = VPRealmManager.restore(url: fileURL) else {
                self?.closeExtension()
                return
            }
            
            let sharedDefaults = UserDefaults(suiteName: Key.AppGroup.Identifier)!
            sharedDefaults.set(tmpURL.absoluteString, forKey: "backup_file_key")
            // 弃用synchronize()，系统会自动同步
            self.openVoicepaperApp(path: "restore")
        }
    } else {
        closeExtension()
    }
}

// 修改后的open方法，添加完成回调
func openVoicepaperApp(path: String = "") {
    guard let url = URL(string: "voicepaper2://" + path), let context = extensionContext else {
        closeExtension()
        return
    }
    context.open(url) { [weak self] success in
        print("打开主应用结果：\(success)")
        self?.closeExtension()
    }
}

2. 适配iOS 18的URL Scheme权限与处理逻辑 #

• 检查Info.plist配置：确认主应用的CFBundleURLTypes中已正确注册voicepaper2 scheme，且扩展的Info.plist中未限制对主应用的调用权限。
• 切换到SceneDelegate处理URL：iOS 13+推荐使用SceneDelegate处理URL跳转，iOS 18可能不再优先触发AppDelegate的open方法，需添加SceneDelegate的处理逻辑：

// SceneDelegate.swift
func scene(_ scene: UIScene, openURLContexts URLContexts: Set<UIOpenURLContext>) {
    guard let url = URLContexts.first?.url else { return }
    let DefaultsForAppGroup = UserDefaults(suiteName: Key.AppGroup.Identifier)!
    if url.absoluteString.contains("restore"), let fileUrl = DefaultsForAppGroup.object(forKey: "backup_file_key") as? String,
       let backupFileURL = URL(string: fileUrl)
    {
        // 执行恢复操作
    }
}

3. 改用Universal Links替代URL Scheme #

iOS 18对URL Scheme的调用限制可能进一步收紧，Universal Links是更稳定的替代方案：

1. 配置主应用的Universal Links（需完成域名验证、上传apple-app-site-association文件等步骤）
2. 在扩展中调用Universal Links：

func openVoicepaperApp(path: String = "") {
    guard let url = URL(string: "https://yourdomain.com/restore") else { return }
    extensionContext?.open(url, completionHandler: { success in
        // 处理结果
    })
}

3. 在主应用的SceneDelegate中通过continueUserActivity处理：

func scene(_ scene: UIScene, continue userActivity: NSUserActivity) {
    if userActivity.activityType == NSUserActivityTypeBrowsingWeb, let url = userActivity.webpageURL {
        // 解析Universal Links并执行对应逻辑
        if url.path.contains("/restore") {
            // 读取共享数据并恢复
        }
    }
}

4. 优化共享数据的传递方式 #

弃用UserDefaults的synchronize()方法（已废弃），改用更可靠的共享文件或FileCoordinator处理跨应用数据传递，避免iOS 18中可能的同步延迟问题：

// 示例：用共享文件传递路径
func saveBackupPathToSharedGroup(url: URL) {
    guard let sharedContainer = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: Key.AppGroup.Identifier) else { return }
    let filePath = sharedContainer.appendingPathComponent("backup_path.txt")
    try? url.absoluteString.write(to: filePath, atomically: true, encoding: .utf8)
}

// 主应用读取
func readBackupPathFromSharedGroup() -> URL? {
    guard let sharedContainer = FileManager.default.containerURL(forSecurityApplicationGroupIdentifier: Key.AppGroup.Identifier) else { return nil }
    let filePath = sharedContainer.appendingPathComponent("backup_path.txt")
    guard let pathString = try? String(contentsOf: filePath) else { return nil }
    return URL(string: pathString)
}

5. 排查系统级限制 #

• 确认测试设备的iOS 18版本为正式版或最新测试版，排除beta版的临时bug
• 检查主应用是否被系统限制启动（如后台刷新权限、App Tracking Transparency权限等）

内容的提问来源于stack exchange，提问作者Umeumeume