如何在SFSafariViewController中添加自定义活动？

import SafariServices

class CustomActivity: UIActivity {
    override var activityType: UIActivity.ActivityType? {
        return UIActivity.ActivityType("com.example.customactivity")
    }
    
    override var activityTitle: String? {
        return "Custom Activity"
    }
    
    override var activityImage: UIImage? {
        return UIImage(named: "custom_activity_icon")
    }
    
    override func canPerform(withActivityItems activityItems: [Any]) -> Bool {
        // 检查是否可以处理指定的活动项
        return true
    }
    
    override func prepare(withActivityItems activityItems: [Any]) {
        // 准备工作
    }
    
    override func perform() {
        // 执行自定义活动的操作
    }
}

class ViewController: UIViewController, SFSafariViewControllerDelegate {
    func openSafariViewController() {
        let url = URL(string: "https://www.example.com")!
        let safariViewController = SFSafariViewController(url: url)
        safariViewController.delegate = self
        
        // 添加自定义活动到活动列表中
        safariViewController.excludedActivityTypes = [UIActivity.ActivityType("com.example.customactivity")]
        
        present(safariViewController, animated: true, completion: nil)
    }
    
    // 返回包含自定义活动的数组
    func safariViewController(_ controller: SFSafariViewController, activityItemsFor URL: URL, title: String?) -> [UIActivity] {
        let customActivity = CustomActivity()
        return [customActivity]
    }
    
    // 在加载完成后执行自定义活动
    func safariViewController(_ controller: SFSafariViewController, didCompleteInitialLoad didLoadSuccessfully: Bool) {
        if didLoadSuccessfully {
            // 执行自定义活动
            let customActivity = CustomActivity()
            customActivity.perform()
        }
    }
}