using response in multiple places in iOS - ios

Question

I tried a lot of methods from stackoverflow and from googling
but I got no luck of reaching what I need.
simply I want to store the response from api request to some variable
so that I can use it freely.
here is the code
import UIKit
class ViewController: UIViewController {
#IBOutlet weak var responseLabel: UILabel!
let apiUrlStr = "http://jsonplaceholder.typicode.com/posts"
var resData = NSArray()
override func viewDidLoad() {
super.viewDidLoad()
request(.GET, apiUrlStr, encoding: .JSON).responseJSON { (_, _, JSON, _) in
let arr = JSON as NSArray
let user = arr[0] as NSDictionary
self.responseLabel.text = user.objectForKey("title") as? String
self.resData = JSON as NSArray //i cant get this from outside
}
println(resData) //prints nothing but empty parentheses while inside the request it prints the data right
}
}
because I have multiple classes and every class need to handle the response in a different way I want to create an api class with a response method that will return the response.
something like this maybe:
class api{
func req(url: String, params: NSDictionary){
//method goes here
}
func res() -> NSDictionary{
//method goes here
var response = NSDictionary()
return response
}
}
then use it like this in viewdidload
let params = ["aaa","bbb"]
let api = api()
api.req(apiUrlStr, params)
let res = api.res()
***by the way the request method I'm using right now is from Alamofire.swift and I dont mind using another method
here is some of the posts and sites I tried to follow without a luck
proper-way-to-pull-json-api-resoponse
link2
all lead to the same result response only from inside the method.

Answer 1

The problem is that the call to the network (looks like you're using alamofire) is asynchronous. So the network request is started and before it completes, your
println(resData)
line executes. At this point the response from the network hasn't returned so resData is still an empty array.
Try doing this instead:
Add a new function
func handleResponse(resData: NSArray) {
self.resData = resData
println(resData)
}
Then in the response code replace
self.resData = JSON as NSArray
with
let resData = JSON as NSArray
self.handleResponse(resData)
Assuming you need more than just a println statement to change when the data is loaded, you will also need to inform things like table views or other UI components to reload their data source in this method.