XML Parser not organizing data into tables - swift

Question

I'm creating an app that involves parsing XML files of a website and putting the information into a table view. Currently the storyboard stands as a tabbed view application with 4 table view controllers connecting to it. I have developed the accompanying class file and set one of the controllers to run off of it. However, the class, while it gives no error, is not returning and creating any tables. The screen is blank just as before there were any swift files. The file is shown below
import UIKit
class Newspage: UITableViewController, NSXMLParserDelegate
{
var parser: NSXMLParser = NSXMLParser()
var info: [newsarticle] = []
var postTitle: String = String()
var postDesc: String = String()
var eName: String = String()
override func viewDidLoad() {
super.viewDidLoad()
super.viewDidLoad()
let url:NSURL = NSURL(string: "http://brrsd.k12.nj.us/rss/News.xml")!
parser = NSXMLParser(contentsOfURL: url)!
parser.delegate = self
parser.parse()
// Uncomment the following line to preserve selection between presentations
// self.clearsSelectionOnViewWillAppear = false
// Uncomment the following line to display an Edit button in the navigation bar for this view controller.
//self.navigationItem.rightBarButtonItem = self.editButtonItem()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
func parser(parser: NSXMLParser, didStartElement elementName: String, namespaceURI namespaceURI: String?, qualifiedName qualifiedName: String?, attributes attributeDict: [String : String])
{
eName = elementName
if elementName == "item" {
postTitle = String()
postDesc = String()
}
}
func parser(parser: NSXMLParser!, foundCharacters string: String!) {
let data = string.stringByTrimmingCharactersInSet(NSCharacterSet.whitespaceAndNewlineCharacterSet())
if (!data.isEmpty) {
if eName == "title" {
postTitle += data
} else if eName == "description" {
postDesc += data
}
}
}
func parser(parser: NSXMLParser!, didEndElement elementName: String!, namespaceURI: String!, qualifiedName qName: String!) {
if elementName == "item" {
let newsart: newsarticle = newsarticle()
newsart.title = postTitle
newsart.description = postDesc
info.append(newsart)
}
}
// MARK: - Table view data source
override func numberOfSectionsInTableView(tableView: UITableView) -> Int {
// #warning Incomplete implementation, return the number of sections
return 1
}
override func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
// #warning Incomplete implementation, return the number of rows
return info.count
}
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as UITableViewCell
let news: newsarticle = info[indexPath.row]
cell.textLabel!.text = news.title
return cell
}
/*
// Override to support conditional editing of the table view.
override func tableView(tableView: UITableView, canEditRowAtIndexPath indexPath: NSIndexPath) -> Bool {
// Return false if you do not want the specified item to be editable.
return true
}
*/
/*
// Override to support editing the table view.
override func tableView(tableView: UITableView, commitEditingStyle editingStyle: UITableViewCellEditingStyle, forRowAtIndexPath indexPath: NSIndexPath) {
if editingStyle == .Delete {
// Delete the row from the data source
tableView.deleteRowsAtIndexPaths([indexPath], withRowAnimation: .Fade)
} else if editingStyle == .Insert {
// Create a new instance of the appropriate class, insert it into the array, and add a new row to the table view
}
}
*/
/*
// Override to support rearranging the table view.
override func tableView(tableView: UITableView, moveRowAtIndexPath fromIndexPath: NSIndexPath, toIndexPath: NSIndexPath) {
}
*/
/*
// Override to support conditional rearranging of the table view.
override func tableView(tableView: UITableView, canMoveRowAtIndexPath indexPath: NSIndexPath) -> Bool {
// Return false if you do not want the item to be re-orderable.
return true
}
*/
/*
// MARK: - Navigation
// In a storyboard-based application, you will often want to do a little preparation before navigation
override func prepareForSegue(segue: UIStoryboardSegue, sender: AnyObject?) {
// Get the new view controller using segue.destinationViewController.
// Pass the selected object to the new view controller.
}
*/
}
Where is the error?
Note: the newsarticle class just contains 2 variables, title and description.

Answer 1

I think your problem is you do not ask your table to refresh itself when you're done parsing the XML.
you need to tell the table to refresh itself when you want it to, by using tableView.reloadData().
You can do this at the end of each element or when the parse is ended by calling reloaData in the delegate function parserDidEndDocument(_ parser: NSXMLParser).
Also, you should not need to call two times super.viewDidLoad() in viewDidLoad.
I'd be you I also would separate the viewController class and the parser delegate in two independent classes.
your cellForRowAtIndexPath is also bothering me:
I don't think you need the second argument (indexPath) to get the cell. You don't want to get the cell a IndexPath but to return a cell to put at IndexPath.
tableView.dequeueReusableCellWithIdentifier("Cell") should get you a cell with the 'Cell' identifier that is available for reuse. For exemple when you scroll down the cell on the top that are not displayed anymore get reused for display on the bottom.
here is how I would implement this function
override func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell: UITableViewCell
if let reusedCell = tableView.dequeueReusableCellWithIdentifier("Cell") {
cell = reusedCell
} else {
cell = UITableViewCell(style: .Default, reuseIdentifier: "Cell")
}
if let label = cell.textLabel {
let news = info[indexPath.row]
label.text = news.title
}
return cell
}