Swift Table index out of Range - swift

Question

I am new to swift and have set up a table which fills using data from an sql database.
The table loads fine but occasionally it gives the error:
"Fatal Error: Index out of range".
It doesn't happen all the time just every now and again.
Also I have migrated from parse to using sql and http requests. Have I taken the correct approach to this when populating the data into the table?
Any help much appreciated!
#IBOutlet var tableView: UITableView!
var tableData = [String]()
var tableImages = [String]()
override func viewDidLoad() {
super.viewDidLoad()
}
override func viewDidAppear(animated: Bool) {
if Reachability.isConnectedToNetwork() == true {
self.tableView.hidden = true
self.tableData.removeAll(keepCapacity: true)
self.tableImages.removeAll(keepCapacity: true)
var nib = UINib(nibName: "vwTblCell3", bundle: nil)
tableView.registerNib(nib, forCellReuseIdentifier: "cell3")
let request = NSURLRequest(URL: NSURL(string: "********.php")!)
NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue(), completionHandler:{
(response: NSURLResponse?, data: NSData?, error: NSError?)-> Void in
let str2 = String(data: data!, encoding: NSUTF8StringEncoding)
let str3 = Int(str2!)!
let url = NSURL(string: "********")!
let task = NSURLSession.sharedSession().dataTaskWithURL(url) { (data, response, error) -> Void in
if let urlContent = data {
do {
let jsonResult = try NSJSONSerialization.JSONObjectWithData(urlContent, options: NSJSONReadingOptions.MutableContainers)
print(str3)
var i = 0
while i < str3 {
print(jsonResult[i]["title"]! as! String)
print(jsonResult[i]["image"]! as! String)
self.tableData.append(jsonResult[i]["title"]! as! String)
self.tableImages.append(jsonResult[i]["image"]! as! String)
i = i + 1
dispatch_async(dispatch_get_main_queue(), { () -> Void in
self.tableView.reloadData()
})
}
} catch {
print("JSON serialization failed")
}
}
}
task.resume()
});
print(tableData)
self.tableView.hidden = false
}
}
// 2
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.tableData.count
}
// 3
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell: TblCell3 = self.tableView.dequeueReusableCellWithIdentifier("cell3") as! TblCell3
cell.lblAffiliate.text = tableData[indexPath.row]
let url3 = NSURL(string: "https://www.********.co.uk/\(tableImages[(indexPath as NSIndexPath).row]).png")
cell.affiliateImage.sd_setImageWithURL(url3)
return cell
}
// 4
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
print("Row \(indexPath.row) selected")
}
// 5
func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return 400
}
}

Answer 1

I hope this helps. I changed a couple small things around for better code (half could be considered bias). I think the issue is mostly that you were reloading the tableView in the loop. Everything else was just a slightly better way to handle this case. I put everything in viewDidLoad, and made the tableView load empty input prequel to receiving data. I think this is more standard for handling this scenario. If you need any other help let me know.
class ViewController: UIViewController {
#IBOutlet var tableView: UITableView!
var tableData: [String] = []
var tableImages: [String] = []
override func viewDidLoad() {
super.viewDidLoad()
if Reachability.isConnectedToNetwork() == true {
var nib = UINib(nibName: "vwTblCell3", bundle: nil)
tableView.registerNib(nib, forCellReuseIdentifier: "cell3")
let request = NSURLRequest(URL: NSURL(string: "********.php")!)
NSURLConnection.sendAsynchronousRequest(request, queue: NSOperationQueue(), completionHandler:{
(response: NSURLResponse?, data: NSData?, error: NSError?)-> Void in
let str2 = String(data: data!, encoding: NSUTF8StringEncoding)
let str3 = Int(str2!)!
let url = NSURL(string: "********")!
let task = NSURLSession.sharedSession().dataTaskWithURL(url) { (data, response, error) -> Void in
if let urlContent = data {
do {
let jsonResult = try NSJSONSerialization.JSONObjectWithData(urlContent, options: NSJSONReadingOptions.MutableContainers)
self.tableData = []
self.tableImages = []
for i in 0..<str3 {
self.tableData.append(jsonResult[i]["title"]! as! String)
self.tableImages.append(jsonResult[i]["image"]! as! String)
}
dispatch_async(dispatch_get_main_queue()) {
self.tableView.reloadData()
}
} catch {
print("JSON serialization failed")
}
}
}
task.resume()
});
}
}
func tableView(tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
return self.tableData.count
}
func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
let cell: TblCell3 = self.tableView.dequeueReusableCellWithIdentifier("cell3") as! TblCell3
cell.lblAffiliate.text = tableData[indexPath.row]
let url3 = NSURL(string: "https://www.********.co.uk/\(tableImages[(indexPath as NSIndexPath).row]).png")
cell.affiliateImage.sd_setImageWithURL(url3)
return cell
}
func tableView(tableView: UITableView, didSelectRowAtIndexPath indexPath: NSIndexPath) {
print("Row \(indexPath.row) selected")
}
func tableView(tableView: UITableView, heightForRowAtIndexPath indexPath: NSIndexPath) -> CGFloat {
return 400
}
}

Answer 2

The problem is that your call to reloadData() is inside the while loop in which you are building tableData and tableImages. Move that after the while loop, by which point both of those arrays will be fully populated.