相关疑难解决方法(0)

我遇到了一个问题,我发生了多个异步请求,从Facebook API和我的Firebase数据库中获取图像和信息.我想执行所有异步请求,然后将我从Facebook API/Firebase数据库中获取的所有数据存储到一个可以快速加载的整个对象中.我已经为每个异步请求设置了完成处理程序,我认为这会强制程序"等待"直到请求完成,然后让程序继续,但这对我来说似乎不起作用.以下是我的尝试:

func setupEvents(completion: (result: Bool, Event: Event) -> Void){
    // Get a reference to Events
    eventsReference = Firebase(url:"<DB Name>")
    eventAttendeesRef = Firebase(url:"<DB Name>")

    //Read the data at our posts reference
    println("Event References: \(eventsReference)")
    eventsReference.observeEventType(FEventType.ChildAdded, withBlock: { (snapshot) -> Void in

        let eventName = snapshot.value["eventName"] as? String
        let eventLocation = snapshot.value["eventLocation"] as? String
        let eventCreator = snapshot.value["eventCreator"] as? String

        var attendees: NSMutableDictionary = [:]
        var attendeesImages = [UIImage]()
        let attendee: NSMutableDictionary = [:]

        let group = dispatch_group_create()

        //Get attendees …