我创建了这个基本架构来处理我的网络问题,
我想让它保持模块化和结构化:
public class NetworkManager {
public private(set) var queue: DispatchQueue = DispatchQueue(label: "com.example.app.dispatchgroups", attributes: .concurrent, target: .main)
public private(set) var dispatchGroup: DispatchGroup = DispatchGroup()
private static var sharedNetworkManager: NetworkManager = {
let networkManager = NetworkManager()
return networkManager
}()
private init() {}
class func shared() -> NetworkManager {
return sharedNetworkManager
}
public func getData() {
dispatchGroup.enter()
queue.async(group: dispatchGroup) {
Alamofire.request(Content.url).responseJSON { response in
switch response.result {
case .success(let value):
let json = JSON(value)
// do some stuff and save to Content struct
Content.annotations += [Station(...)]
case .failure(let error):
print("error: ",error)
}
}
self.dispatchGroup.leave()
}
}
}
struct Content {
static var url = "url"
static var annotations = [Station]()
}
所以当我在单独的类中调用它时:
class MainViewController {
override func viewDidLoad() {
super.viewDidLoad()
// some stuff ...
NetworkManager.shared().getData()
NetworkManager.shared().dispatchGroup.notify(queue: DispatchQueue.main) {
self.mapView.removeAnnotations(Content.annotations)
self.mapView.addAnnotations(Content.annotations)
}
}
}
但是,似乎在所有请求完成之前执行了 DispatchGroup().notify()...因为没有向 mapview 添加注释。
我已经检查并加载了注释。
有人可以帮我解决这个架构吗?
谢谢和问候!
最佳答案
我认为您需要将 self.dispatchGroup.leave()
放入 Alamofire
响应处理程序中。正如所写,您在排队请求后立即离开。
queue.async(group: dispatchGroup) {
Alamofire.request(Content.url).responseJSON { response in
switch response.result {
case .success(let value):
let json = JSON(value)
// do some stuff and save to Content struct
Content.annotations += [Station(...)]
case .failure(let error):
print("error: ",error)
}
self.dispatchGroup.leave()
}
}
关于iOS - swift 3 - DispatchGroup,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/41654959/