Ytukyg

I have an issue with saving struct into Array of struct after fetched from API. After I finish fetching the JSON data and using completion, the data cannot be appended into array inside completion block. I've been looking around for couple days, tried many things, and still doesn't work.

Here is the code:

import UIKit



struct IndodaxApi:Decodable{

    var ticker:dataStruct

}



struct dataStruct: Decodable {

    var high:String

    var low:String

    var last:String

    var vol_idr:String

    var vol_btc:String



    init(high:String, low:String, last:String, vol_idr:String, vol_btc:String) {

        self.high = high

        self.low = low

        self.vol_idr = vol_idr

        self.vol_btc = vol_btc

        self.last = last

    }



    func printInfo() -> Void {

        print("High:(high)")

        print("Low:(low)")

        print("Last:(last)")

        print("vol_idr:(vol_idr)")

        print("vol_btc:(vol_btc)")

    }

}



class data {

    private let link:String

    private let ticker:String

    private let coinlist_idr:[String]

    private var dataCoin:[dataStruct]



    init() {

        link = "https://indodax.com/api/"

        ticker = "/ticker"

        coinlist_idr = ["btc_idr"]

        dataCoin = [dataStruct]()

    }



    public func getData() -> [dataStruct] {

        dataCoin.removeAll()

        load()

        return dataCoin

    }

This function here means to append data returned from completionhandler into dataCoin array which is struct of DataStruct:

private func load(){

    var index = 0

    let totalCoin = coinlist_idr.count

    while(index<totalCoin){

        fetchcoin(coinName: getNextCoin(index), completionHandler: { (data) in

            self.dataCoin.append(data)

        })

        index+=1

    }

}

This function here is to fetch the data from API and pass into completionhandler:

public func fetchcoin(coinName:String, completionHandler: @escaping ((dataStruct)->Void)){

    let urlLink = self.link + coinName + self.ticker;

    let url = URL(string: urlLink)



    URLSession.shared.dataTask(with: url!) { (data, response, err) in

        guard let data = data else {return}

        do {

            let api = try JSONDecoder().decode(IndodaxApi.self, from: data)

            DispatchQueue.main.async {

                let returnData = dataStruct(high: api.ticker.high, low: api.ticker.low, last: api.ticker.last, vol_idr: api.ticker.vol_idr, vol_btc: api.ticker.vol_btc)

                completionHandler(returnData)

            }

        }catch let jsonERR{

            print(jsonERR)

        }

    }.resume()

}



private func getNextCoin(_ coinName:Int)->String{

    return coinlist_idr[coinName]

}