Trying to get new value from a component on custom table cell class

I have an app which have a table view

and iam using custom cell class in my table

and this is my custom table cell class :

class addCommentTableViewCell: UITableViewCell {

    override func awakeFromNib() {
        super.awakeFromNib()
        // Initialization code

        postText.layer.borderWidth = 1
        postText.layer.borderColor = UIColor.grayColor().CGColor

        postText.layer.cornerRadius = 3


    }

    @IBOutlet weak var postText: UITextView!

    @IBOutlet weak var postCommentButton: UIButton!
    override func setSelected(selected: Bool, animated: Bool) {
        super.setSelected(selected, animated: animated)

        // Configure the view for the selected state
    }

}

i need to click the button in the cell class and get the value from the textView

so i added this code to make that :

    class singleNewViewController: UIViewController  , UITableViewDataSource  , UITableViewDelegate{

     override func viewDidLoad() {

        let indexPath = NSIndexPath(forRow: 1, inSection: 0)

        let secondCellPostComment = mainTable.dequeueReusableCellWithIdentifier("addCommentCell" , forIndexPath: indexPath) as! addCommentTableViewCell


        let postButton =    secondCellPostComment.postCommentButton

         postButton!.addTarget(self, action: "postUserComment", forControlEvents: .TouchUpInside)



      }

func postUserComment()
    {


        let indexPath = NSIndexPath(forRow: 1, inSection: 0)
        let secondCellPostComment = mainTable.dequeueReusableCellWithIdentifier("addCommentCell" , forIndexPath: indexPath) as! addCommentTableViewCell

    var textFieldComment = secondCellPostComment.postText
        let textF =    textFieldComment.text!



       let request = NSMutableURLRequest(URL: NSURL(string:  "http://mydomain/comment")!)


         request.HTTPMethod = "POST"
        let postString = "user_id=(addResourcesViewController.userLoggedID)&news_id=(singleNewViewController.newID)&comment=(textF.text!)"
        request.HTTPBody = postString.dataUsingEncoding(NSUTF8StringEncoding)

        let task = NSURLSession.sharedSession().dataTaskWithRequest(request) {
            data , response , error in

            guard error == nil && data != nil else {                                                          // check for fundamental networking error
                print("error=(error)")
                return
            }


            if let httpStatus = response as? NSHTTPURLResponse where httpStatus.statusCode != 200 {           // check for http errors
                print("statusCode should be 200, but is (httpStatus.statusCode)")
                print("response = (response)")
            }


            let responseString = NSString(data: data!, encoding: NSUTF8StringEncoding)


            dispatch_async(dispatch_get_main_queue(), {
                self.mainTable.reloadData()

            })

        }
        task.resume()     
    }

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {

    if (indexPath.row == 0 )
    {
    let cell = mainTable.dequeueReusableCellWithIdentifier("singleTableDetails", forIndexPath: indexPath) as! singleNewTableViewCell










    let readmorebutton = cell.readmore
    let focusComment = cell.addcomments



        readmorebutton.addTarget(self, action: "loadURLinBrowser", forControlEvents: UIControlEvents.TouchUpInside)


        focusComment.addTarget(self, action: "focusToView", forControlEvents: UIControlEvents.TouchUpInside)


        let remoteImageUrlString = "http://mydomian/"+singleNewViewController.image
        let imageURL = NSURL(string: remoteImageUrlString)

        let myBlock: SDWebImageCompletionBlock! = { (image:UIImage! , error : NSError! , cacheType: SDImageCacheType! , imageURL: NSURL! ) -> Void in
            print("Image with urk  (imageURL.absoluteString) is loaded" )

        }


        cell.cellImage.sd_setImageWithURL(imageURL, placeholderImage: UIImage(named:"welcome_bg") , options: SDWebImageOptions.ProgressiveDownload, completed: myBlock)



   return cell

    }else if (indexPath.row == 1 )
    {
        let cell = mainTable.dequeueReusableCellWithIdentifier("addCommentCell", forIndexPath: indexPath) as! addCommentTableViewCell





       return cell
    }


    else
    {
        let cell = mainTable.dequeueReusableCellWithIdentifier("allCommentsCell", forIndexPath: indexPath) as! commentsTableViewCell
        cell.commentUser.text = self.commentsUser[(indexPath.row - 2)]
        cell.comment.text = self.comments[(indexPath.row - 2)]

            return cell
    }


}





    }

the code is working but i don't get the value of the UITextView

and i tried to add a default value to the UITextView from the storyboard it's working but when i run in simulator and replace it with any string it's send the default value to the url any suggestion why it's not read any new values ?