swift 2如何在函數外使用變量？

Question

我從本教程中學到了一個類ApiManager（）來請求JSON數據，該類使用協議委托方法將數據傳遞給ViewController類。

數據可以很好地獲取，但我不確定如何使用它！ 在這種情況下，我試圖在TableView中使用它

class ViewController: UITableViewController, ApiManagerDelegate{

var names:[String] = []  // the variable which will hold the JSON data

override func viewDidLoad() {
    super.viewDidLoad()

    //instantiate the ApiManager Class
    //Set the ViewController as its delegate
    //perform request to Restaurants info

    let manager = ApiManager()
    manager.delegate = self
    manager.getRestaurantsData()

    func didReceiveResponse (info: [String : AnyObject]){

        //Read name property from data dictionary (JSON)

        if let restaurantsData = info["restaurants"] as? [[String: AnyObject]]{

            for restaurant in restaurantsData{
                let name = restaurant["name"] as? String
                self.names.append(name!)
            }
        }


        print("Data1: \(names)") // prints the data perfectly

    }

    func didFailToReceiveResponse() {
        print("There was an error in recieving API data")
    }

}

override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    print (names) //no data here
    return names.count //not working
}

我有點困惑如何解決此問題，我試圖為didReieveResponse（）返回值，但是問題是當我調用該函數時需要參數（在Delegator類“ dictionary”類中傳遞給它）。我完全感到困惑。

這是供參考的委托類和協議：

import UIKit

//Custom Protocol Declaration
@objc protocol ApiManagerDelegate {
    optional func didReceiveResponse(info: [ String : AnyObject ])
    optional func didFailToReceiveResponse()
}


class ApiManager: NSObject, NSURLSessionDelegate {

//open restaurant web API
private let requestURL = NSURL(string:"http://some-url-here.com")

var delegate: ApiManagerDelegate?

override init() {

    super.init()

}

func getRestaurantsData() {

    let defaultConfigObject = NSURLSessionConfiguration.defaultSessionConfiguration()

    let defaultSession = NSURLSession (configuration: defaultConfigObject, delegate: self, delegateQueue: NSOperationQueue.mainQueue ())

    let request = NSMutableURLRequest(URL: requestURL!, cachePolicy: NSURLRequestCachePolicy.ReloadIgnoringCacheData, timeoutInterval: 60 )



    request.HTTPMethod = "POST"
    request.setValue( "application/x-www-form-urlencoded" , forHTTPHeaderField: "Content-Type" )

    let dataTask = defaultSession.dataTaskWithRequest(request, completionHandler: { (data: NSData?, response: NSURLResponse?, error: NSError?) in

            if let responseError = error {

                self.delegate?.didFailToReceiveResponse?()
                print("Reponse Error: \( responseError )" )

                } else {
                    do {
                        let dictionary = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions.MutableContainers) as! [String: AnyObject]

                        self.delegate?.didReceiveResponse?(dictionary)
                        //print( "Response: \( dictionary )" )
                        print("Response: Success")

                    } catch let jsonError as NSError {
                        // Handle parsing error
                        self.delegate?.didFailToReceiveResponse?()
                        print( "JSONError: \(jsonError.localizedDescription)")
                    }
                }
            })

            dataTask.resume()
}

}

謝謝，

---

更新：

對於將來可能像我一樣遭受痛苦的開發人員，解決方案是使用TableViewName.reloadData（），如下所述。。但是請注意，僅當我將DidRecieveResponse（）函數放在ViewDidLoad之外時，它才與我一起工作，不知道為什么希望其中之一專家可以稍后解釋。

請享用！

Answer 1

喜歡

 class ViewController: UITableViewController, ApiManagerDelegate{

var names:[String] = []  
 let manager = ApiManager()


 override func viewDidLoad() {
    super.viewDidLoad()

    manager.delegate = self
    manager.getRestaurantsData()
 }

   func didReceiveResponse (info: [String : AnyObject]){

        //Read name property from data dictionary (JSON)

        if let restaurantsData = info["restaurants"] as? [[String: AnyObject]]{

            for restaurant in restaurantsData{
                let name = restaurant["name"] as? String
                self.names.append(name!)
            }

                print("Data1: \(names)") // prints the data perfectly
             if (self.names.count>0)
             { 
              yourtableview.reloadData()
             }
        }

    }


  func didFailToReceiveResponse() {
    print("There was an error in recieving API data")
}