1.创建的子类UIActivity。

实现该类的所有必需方法，并在初始化活动时传入该页面的URL并初始化your UIViewController，这prepareWithActivityItems:在SFSafariViewController上下文中没有被调用（rdar：// 24138390）。如果您的活动未显示UI，请在初始化期间保存URL，以便您在用户点击操作时进行处理。

完整示例：

@interface YourActivity : UIActivity {
    UIViewController *activityViewController;
}
- (id)initWithURL:(NSURL *)url;
@end


@implementation YourActivity

- (id)initWithURL:(NSURL *)url
{
    self = [super init];
    if (self)
    {
        [self prepareWithURL:url];
    }
    return self;
}

- (NSString *)activityType
{
    return @"YourTypeName";
}

- (NSString *)activityTitle
{
    return @"Perform Action";
}

- (UIImage *)activityImage
{
    return [UIImage imageNamed:@"YourActionIcon"];
}

- (BOOL)canPerformWithActivityItems:(NSArray *)activityItems
{
    return YES;
}

- (void)prepareWithActivityItems:(NSArray *)activityItems
{
    NSURL* url = nil;
    for (NSObject* obj in activityItems)
    {
        if ([obj isKindOfClass:[NSURL class]])
        {
            url = (NSURL*)obj;
        }
    }
    
    [self prepareWithURL:url];
}

- (void) prepareWithURL:(NSURL*)url
{
    // initialize your UI using the given URL
    activityViewController = ... // initialize your UI here
}

- (UIViewController *)activityViewController
{
    return activityViewController;
}

+ (UIActivityCategory)activityCategory
{
    return UIActivityCategoryShare;
}


@end

2.添加UIActivity到SFSafariViewController

在中实现以下方法SFSafariViewControllerDelegate，该方法将初始化活动并传递用户正在查看的页面的URL。

- (NSArray<UIActivity *> *)safariViewController:(SFSafariViewController *)controller
                            activityItemsForURL:(NSURL *)URL
                                          title:(NSString *)title
{
    YourActivity* activity = [[YourActivity alloc] initWithURL:URL];
    return @[activity];
}