ios - IGListKit 从 Alamofire 请求向类插入数据

Question

所以我有这个模型

class Event: NSObject {
    var _eventName: String!
    var _venueName : String!
    var _eventImage: String!


    var eventName: String {
        if _eventName == nil {
            _eventName = ""
        }
        return _eventName
    }

    var venueName: String {
        if _venueName == nil {
            _venueName = ""
        }
        return _venueName
    }

    var eventImage: String {
        if _eventImage == nil {
            _eventImage = ""
        }
        return _eventImage
    }

    init(eventsDict: Dictionary<String, AnyObject>) {
        if let venue = eventsDict["venue"] as? Dictionary<String, AnyObject> {
            if let venuname = venue["name"] as? String{
                self._venueName = venuname
            }
        if let eventname = eventsDict["name"] as? String {
            self._eventName = eventname
        }
        if let eventimage = eventsDict["coverPicture"] as? String {
            self._eventImage = eventimage
        }
    }
}

我用这个扩展使它成为 IGListDiffable。

extension NSObject: IGListDiffable {

    public func diffIdentifier() -> NSObjectProtocol {
        return self
    }

    public func isEqual(toDiffableObject object: IGListDiffable?) -> Bool {
        return isEqual(object)
    }
}

所以当我像这样从硬编码代码加载数据时

var entries = [Event]()
func loadFakeEvents() {
        let entries = [
        Event(
            eventName: "Ζωρζ Πιλαλι Και Η Soufra Band Στο AN Groundfloor - Live Stage!",
            venueName: "AN Groundfloor - live stage",
            eventImage: "https://scontent.xx.fbcdn.net/v/t31.0-8/s720x720/15936729_1867160333520142_8855370744955080264_o.jpg?oh=8198bc10a8ea61011d7ec1902b34aa01&oe=593D6BC4"
            ),
        Event(
            date: "2017-02-18T21:30:00+0200",
            name: "Διονύσης Σαββόπουλος at Gazarte I Main Stage 18/02",
            venuename: "Gazarte",
            eventImage: "https://scontent.xx.fbcdn.net/v/t1.0-9/s720x720/16265335_1262826863809003_3636661375515976849_n.jpg?oh=5bb342321a65d33dbc1cc41de266b45e&oe=5907857C"
            )
        ]
        self.entries = entries
    }

事件加载正常。因为他们必须这样做。

但是当我发出 alamofire 请求时，当然需要一些时间来加载数据并将它们附加到空的事件数组中。

这是我必须调用事件的函数

    func loadEvents() {

        let parameters: Parameters = [
        "Some" : "Parameters",
        "Some" : "Parameters"
        ]
        Alamofire.request(baseurl, method: .get, parameters: parameters)
            .responseJSON { (responseData) -> Void in
                if((responseData.result.value) != nil) {
                    let result = responseData.result

                    if let dict = result.value as? Dictionary<String, AnyObject>{
                        print(dict) // <-- Check this out
                        if let list = dict["events"] as? [Dictionary<String, AnyObject>] {

                            for obj in list {
                                let event = Event(eventsDict: obj)
                                self.entries.append(event)

                            }
                        }
                    }
                }
        }
  }

所以在上面的代码中我有一个 print，它打印 json。

在我的

extension LocationViewController: IGListAdapterDataSource {
    func objects(for listAdapter: IGListAdapter) -> [IGListDiffable] {
        let items: [IGListDiffable] = loader.entries as [IGListDiffable]
        print(items.count)  // <--- another print of items that should be displayed
        return items
    }
    func listAdapter(_ listAdapter: IGListAdapter, sectionControllerFor object: Any) -> IGListSectionController {
        return NormalSectionController()
    }
    func emptyView(for listAdapter: IGListAdapter) -> UIView? { return nil }
}

Adapter i 还打印应该显示的项目。因此，当我加载 fakeEvents 函数时，它会打印 2 但是当我使用普通函数加载它们时，它会打印 0 然后是 JSON 来自 dict 来自先前代码的 var。

通常我会 reloadData() Collection View 。但是使用 IGListKit 将事件类发送到 CollectionView 的技巧是什么？非常感谢您抽出时间，我希望我没有跑题!

Answer 1

在 Github 上粘贴我在同一问题上的回答，以防有人找到。

https://github.com/Instagram/IGListKit/issues/468

当附加到条目字典时，您似乎在 for 循环之后错过了对 self.adapter.performUpdates(animated: true) 的调用:

func loadEvents() {
  // ...
  Alamofire.request(baseurl, method: .get, parameters: parameters)
    .responseJSON { (responseData) -> Void in

    if responseData.result.value != nil {
      let result = responseData.result
      if let dict = result.value as? Dictionary<String, AnyObject>{
        if let list = dict["events"] as? [Dictionary<String, AnyObject>] {
          for obj in list {
            let event = Event(eventsDict: obj)
            self.entries.append(event)
          }
          // missing this!
          self.adapter.performUpdates(animated: true)
          // missing that!
        }
      }
    }
  }
}