Dfyjkt

I'm trying to abstract an XML parser into a custom class to run it from a VC. It compiles perfectly and my error handler shows up success. However, the actual delegate methods are skipped over. No data is getting parsed.

It all ran fine when I had every running it the VC, but I am now try to get away from spaghetti code.

import UIKit

class ViewController: UIViewController 
 override func viewDidLoad() 
 super.viewDidLoad()

 let parser = XMLParserHelper()
 //try create file for persistent data
 //CreatePlist.createPlist()
 parser.runParser()
 


class XMLParserHelper: NSObject, XMLParserDelegate 
 //list type variables to hold XML values (update list base on XML structure):
 static var station: String = ""
 static var latitude: String = ""
 static var longitude: String = ""
 private static var code: String = ""
 private static var id: String = ""

 //reusable method type veriales (do not touch)
 static var strXMLData:String = ""
 static var currentElement:String = ""
 static var passData:Bool=false
 static var passName:Bool=false
 static var xmlParser = XMLParser()

 //parser methods
 func runParser()
 let xmlPath = Bundle.main.url(forResource: "station", withExtension: "xml")
 let xmlParser = XMLParser(contentsOf: (xmlPath)!)
 xmlParser?.delegate = self
 let success:Bool = xmlParser!.parse()
 xmlParser?.parse()
 if success 
 print("parse success!")
 print(XMLParserHelper.currentElement)
 else 
 print("parse failure!")
 
 

 private static func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String]) elementName=="StationId" ) 
 if (elementName=="StationDesc") 
 XMLParserHelper.passName=true;
 
 XMLParserHelper.passData=true;
 
 

 private static func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) 

 private static func parser(_ parser: XMLParser, foundCharacters string: String) 
 if (XMLParserHelper.passName) 
 XMLParserHelper.strXMLData=XMLParserHelper.strXMLData+"nn"+string
 

 if (XMLParserHelper.passData) 
 //ready content for codable struct
 switch XMLParserHelper.currentElement 
 case "StationDesc":
 XMLParserHelper.station = string
 case "StationLatitude":
 XMLParserHelper.latitude = string
 case "StationLongitude":
 XMLParserHelper.longitude = string
 case "StationCode":
 XMLParserHelper.code = string
 case "StationId":
 XMLParserHelper.id = string
 print(string)

 default:
 XMLParserHelper.id = string
 
 
 

 func parser(_ parser: XMLParser, parseErrorOccurred parseError: Error) 
 print("failure error: ", parseError)
 

To make XMLParserDelegate methods work, all the methods needs to be non-static, non-private methods.

So, all the properties should also be non-static.

class XMLParserHelper: NSObject, XMLParserDelegate 

 //list type variables to hold XML values (update list base on XML structure):
 var station: String = ""
 var latitude: String = ""
 var longitude: String = ""
 private var code: String = ""
 private var id: String = ""

 //reusable method type veriales (do not touch)
 var strXMLData: String = ""
 var currentElement: String = ""
 var passData: Bool = false
 var passName: Bool = false

 //parser methods
 func runParser() 
 let xmlURL = Bundle.main.url(forResource: "station", withExtension: "xml")!
 let xmlParser = XMLParser(contentsOf: xmlURL)!
 xmlParser.delegate = self
 let success = xmlParser.parse()
 if success 
 print("parse success!")
 print(currentElement)
 else 
 print("parse failure!")
 
 

 //MARK: XMLParserDelegate methods

 func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String]) elementName == "StationLongitude"
 

 func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) 

 func parser(_ parser: XMLParser, foundCharacters string: String) 
 if passName 
 strXMLData = strXMLData+"nn"+string
 

 if passData 
 //ready content for codable struct
 switch currentElement 
 case "StationDesc":
 station = string
 case "StationLatitude":
 latitude = string
 case "StationLongitude":
 longitude = string
 case "StationCode":
 code = string
 case "StationId":
 id = string
 print(string)

 default:
 id = string
 
 
 

 func parser(_ parser: XMLParser, parseErrorOccurred parseError: Error) 
 print("failure error: ", parseError)
 

The XMLParser just needs to be held while parse() is running, so you have no need to declare xmlParser as a property of XMLParserHelper.

You need a strong reference

class ViewController: UIViewController
 var parser:XMLParserHelper!
 override func viewDidLoad() 
 super.viewDidLoad()
 parser = XMLParserHelper()
 parser.runParser()