ios - 如何防止 UI 快速卡住？

Question

我在下面的代码中使用 URLSession 时从服务器获取了一些数据。当我在代码中使用此静态方法在其他一些 View Controller 中获取数据(我的意思是 View 加载方法)以填充 Collection View 时，我的 UI 可能会卡住 2 秒，我认为它不应该那样。我的错误在哪里？

 class RelatedData{
    static func get(_ Url:String?,completion:@escaping (Array<Game>,Int)-> Void){
    guard let url = Url else{
        return
    }
    var request = URLRequest(url: URL(string:url  )!)
    var gameArray = [Game]()
    var status:Int!
    request.httpMethod = "GET"

    let task = URLSession.shared.dataTask(with: request) { data, response, error in
        guard let data = data, error == nil else {                                                 // check for fundamental networking error
            print("error=\(String(describing: error))")
            return
        }
        if let httpStatus = response as? HTTPURLResponse, httpStatus.statusCode != 200 {              // check for http errors
            print("statusCode should be 200, but is \(httpStatus.statusCode)")
            print("response = \(String(describing: response))")
        }
        do{
            print("Here we are in related games")
            let allData = try  JSONDecoder().decode(RelaedGameObject.self, from: data)
            status = allData.status
            gameArray = allData.data
            DispatchQueue.main.async{
                let container = gameArray
                completion(container,status)
                gameArray.removeAll()
            }
        }
        catch{
            print(" Related Api Don't Work!!!")
        }
    }
    task.resume()
}

}


//And This Is View Controller Call :  


RelatedData.get(url){(Games,status) in
   if status == 1{      
    self.relatedGames = Games
    if Games.count == 0 {
     self.label.font = UIFont(name: "IRANSans", size: 13)
     self.relatedCollectionView.backgroundView = self.label
     self.relatedLabel.isHidden = false  
    }else{
      self.relatedLabel.isHidden = false
      self.relatedCollectionView.isHidden = false
      self.relatedCollectionView.reloadData()
      self.relatedCollectionView.transform =CGAffineTransform(scaleX: -1.0, y: 1.0)
     self.relatedActivityIndicator.stopAnimating()
}
}else{
print("Err in related games")
   }
  }
}

Answer 1

不是在 get(_:completion:) 方法的 do-catch 语句中添加对 DispatchQueue.main.async 的调用，将它移动到 controller 中，您将在 completion 处理程序中获得响应，即

RelatedData.get(url){(Games,status) in
    DispatchQueue.main.async {
        //add your code here...
    }
}