ios - 快速解析来自rest api的xml数据

Question

我正在尝试从rest api解析xml数据，数据被解析并存储在名为NewslettersParser的类中的数组帖子中，但我无法将其存储在另一个名为MyTableViewController的类中>，这是我的代码:

NewslettersParser.swift:

import Foundation

private var url = NSURL(string: "http://www.iaa.edu.jo/load/iaa/newsletters")

class NewslettersParser: NSObject, NSXMLParserDelegate{

var parser : NSXMLParser! = NSXMLParser(contentsOfURL: url!)
var currentElement:String = ""
var passData:Bool=false
var passName:Bool=false
var postFile:String = ""
var postDate:String = ""
var posts: [Newsletters] = []
var counter: Int = 0
var pageNumber: Int = 1
var news: Newsletters = Newsletters()
let defaults = NSUserDefaults.standardUserDefaults()



func getData() {
    let postEndpoint: String = "http://www.iaa.edu.jo/load/iaa/newsletters"
    let url = NSURL(string: postEndpoint)!
    let request = NSMutableURLRequest(URL: url)
    let session = NSURLSession.sharedSession()
    request.HTTPMethod = "POST"
    let paramString = "page=\(pageNumber)"
    request.HTTPBody = paramString.dataUsingEncoding(NSUTF8StringEncoding)

    session.dataTaskWithRequest(request, completionHandler: { ( data: NSData?, response: NSURLResponse?, error: NSError?) -> Void in
        guard let realResponse = response as? NSHTTPURLResponse where
            realResponse.statusCode == 200 else {
                print("Not a 200 response")
                return
        }
        let newStr = String(data: data!, encoding: NSUTF8StringEncoding)
        print(newStr)

        self.parser = NSXMLParser(data: data!)
        self.parser.delegate = self
        self.parser.parse()

        let success:Bool = self.parser.parse()

        if success {
            print("parse success!")

        } else {
            //error
        }


    }).resume()


}

func parser(parser: NSXMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String]) {
    currentElement=elementName
    if(elementName=="item" || elementName=="date" || elementName=="file"){
        if(elementName=="item"){
            passName=true
        }
        passData=true
    }
}

func parser(parser: NSXMLParser, foundCharacters string: String) {
    if(passData){

         if currentElement=="date"{
            postDate = string
        }
        else if currentElement=="file"{
            postFile = string
        }
    }
}

// func parserDidEndDocument(parser: NSXMLParser){
//    news.fetch(posts)
//}

func parser(parser: NSXMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
    currentElement=""
    let post: Newsletters = Newsletters()

    if(elementName=="item" || elementName=="date" || elementName=="file"){

        if(elementName=="item"){
            passName=false
            post.date = postDate
            post.file = postFile
            posts.append(post)
            counter += 1
            if(counter == 10){
                pageNumber += 1
                counter = 0
                self.getData()
            }
        }
    }
    if(posts.count == 23){
        news.data = posts
    }
    //self.myTable.reloadData()
}


func parser(parser: NSXMLParser, parseErrorOccurred parseError: NSError) {
    NSLog("failure error: %@", parseError)
}


}

这是 MyTableViewController:

import UIKit
import SDWebImage

class MyTableTableViewController: UITableViewController {

@IBOutlet var myTable: UITableView!


var newsletters: [Newsletters] = []
var news: Newsletters = Newsletters()

let Nparse: NewslettersParser = NewslettersParser()

override func viewDidLoad() {
    super.viewDidLoad()
    //
    Nparse.getData()
    newsletters = news.data
    self.myTable.reloadData()

}

和 Newsletters.swift:

class Newsletters{
var file: String = String()
var date: String = String()
var data: [Newsletters] = []
let Nparse: NewslettersParser = NewslettersParser()
 }

提前谢谢您。

Answer 1

委托(delegate)模式非常适合这种情况。您可以在 Controller 解析完成后使用委托(delegate)方法。

委托(delegate)协议(protocol)

protocol NewslettersParserDelegate: class {
    func finishedParsing()
}

**具有委托(delegate)能力的 NewslettersParser.swift **

    import Foundation

    private var url = NSURL(string: "http://www.iaa.edu.jo/load/iaa/newsletters")

    class NewslettersParser: NSObject, NSXMLParserDelegate{

    var parser : NSXMLParser! = NSXMLParser(contentsOfURL: url!)
    var currentElement:String = ""
    var passData:Bool=false
    var passName:Bool=false
    var postFile:String = ""
    var postDate:String = ""
    var posts: [Newsletters] = []
    var counter: Int = 0
    var pageNumber: Int = 1
    var news: Newsletters = Newsletters()
    let defaults = NSUserDefaults.standardUserDefaults()

// delegate property 
weak var newslettersParserDelegate: NewslettersParserDelegate!



    func getData() {
        let postEndpoint: String = "http://www.iaa.edu.jo/load/iaa/newsletters"
        let url = NSURL(string: postEndpoint)!
        let request = NSMutableURLRequest(URL: url)
        let session = NSURLSession.sharedSession()
        request.HTTPMethod = "POST"
        let paramString = "page=\(pageNumber)"
        request.HTTPBody = paramString.dataUsingEncoding(NSUTF8StringEncoding)

        session.dataTaskWithRequest(request, completionHandler: { ( data: NSData?, response: NSURLResponse?, error: NSError?) -> Void in
            guard let realResponse = response as? NSHTTPURLResponse where
                realResponse.statusCode == 200 else {
                    print("Not a 200 response")
                    return
            }
            let newStr = String(data: data!, encoding: NSUTF8StringEncoding)
            print(newStr)

            self.parser = NSXMLParser(data: data!)
            self.parser.delegate = self
            self.parser.parse()

            let success:Bool = self.parser.parse()

            if success {
                print("parse success!")

            } else {
                //error
            }


        }).resume()


    }

    func parser(parser: NSXMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String]) {
        currentElement=elementName
        if(elementName=="item" || elementName=="date" || elementName=="file"){
            if(elementName=="item"){
                passName=true
            }
            passData=true
        }
    }

    func parser(parser: NSXMLParser, foundCharacters string: String) {
        if(passData){

             if currentElement=="date"{
                postDate = string
            }
            else if currentElement=="file"{
                postFile = string
            }
        }
    }

    // func parserDidEndDocument(parser: NSXMLParser){
    //    news.fetch(posts)
    //}

    func parser(parser: NSXMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
        currentElement=""
        let post: Newsletters = Newsletters()

        if(elementName=="item" || elementName=="date" || elementName=="file"){

            if(elementName=="item"){
                passName=false
                post.date = postDate
                post.file = postFile
                posts.append(post)
                counter += 1
                if(counter == 10){
                    pageNumber += 1
                    counter = 0
                    self.getData()
                }
            }
        }
        if(posts.count == 23){
            news.data = posts
        }
        //self.myTable.reloadData() instead of this you can now call 
        newslettersParserDelegate.finishedParsing()
    }


    func parser(parser: NSXMLParser, parseErrorOccurred parseError: NSError) {
        NSLog("failure error: %@", parseError)
    }


    }

现在在您的 MyTableViewController 中，您可以确认委托(delegate)并使用该方法

import UIKit
import SDWebImage

class MyTableTableViewController: UITableViewController, NewslettersParserDelegate {

@IBOutlet var myTable: UITableView!

var newsletters: [Newsletters] = []
var news: Newsletters = Newsletters()

let Nparse: NewslettersParser = NewslettersParser()

override func viewDidLoad() {
    super.viewDidLoad()
    //
    Nparse.getData()
    Nparse.newslettersParserDelegate = self

    newsletters = news.data
    self.myTable.reloadData()

}

func finishedParsing(){
// reload data upon finishing parsing 
}


}