Accessing custom cell object properties on tap of UIButton in same cell SWIFT

Question

I have a custom cell setup with an add and subtract button, and a quantity label. I'd like a label in the view controller to update with the price shown in the cell.

I've scoured SE and the google machine, but all examples are for Objective-C and are satisfied with passing the indexPath.row to the selector. I've managed to pass the row in which the add button was tapped to the selector method, however I can't access the objects in the cell, eg cell.itemNameLabel.text

I've tried implementing in the selector method something similar to the objective-c: with no joy.

UITableViewCell* cell = (UITableViewCell*)[sender superview];
NSIndexPath* indexPath = [myTableView indexPathForCell:cell];

Here is my setup:

Custom Cell:

class ProductListTableViewCell: UITableViewCell {

@IBOutlet var itemNameLabel: UILabel! = UILabel()
@IBOutlet weak var itemImage: UIImageView! = UIImageView()
@IBOutlet var itemPriceLabel: UILabel! = UILabel()
@IBOutlet weak var itemQty: UILabel!
@IBOutlet weak var addItem: UIButton! = UIButton()

Main view controller:

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

    let cell:ProductListTableViewCell = tableView.dequeueReusableCellWithIdentifier("Cell", forIndexPath: indexPath) as ProductListTableViewCell

    let drink:PFObject = self.productListData.objectAtIndex(indexPath.row) as PFObject

    cell.itemImage.layer.cornerRadius = cell.itemImage.frame.size.width / 2
    cell.itemImage.clipsToBounds = true

    cell.addItem.tag = indexPath.row
    cell.addItem.addTarget(self, action:("cellAddItemAction:"), forControlEvents: UIControlEvents.TouchUpInside)

    cell.itemNameLabel.text = drink.objectForKey("name") as? NSString
    cell.calorieLabel.text = drink.objectForKey("calories") as? NSString

    cell.itemPriceLabel.text = drink.objectForKey("price") as? NSString
    cell.itemImage.alpha = 1

    let itemImage = drink["image"] as PFFile

    itemImage.getDataInBackgroundWithBlock{
        (imageData: NSData!, error: NSError!) -> Void in
        if error == nil {
            let image = UIImage(data: imageData)
            cell.itemImage.image = image
        }

    }
    }
)
    return cell
}

Selector method:

func cellAddItemAction(sender: UIButton){

    println("pressed \(sender.tag)")

}

This works but I need to make changes to the objects in the cell, such as cell.itemQty.text.

Hope this is clear, i'm quite new to programming so please be patient with my terminology, I know its not all right!! Thanks for helping.

Answer 1

OK, so I went about it slightly differently. This is a prototype app and needs only to appear to work. Heres what I did if it helps anyone though.

Add a tag to the button being pressed in cellForRowAtIndexPath :

cell.addItem.tag = indexPath.row

Then when adding the target, instead of using Self, use the cell:

cell.addItem.addTarget(cell, action:("cellAddItemAction:"), forControlEvents: UIControlEvents.TouchUpInside)

Declare a global variable in the viewController:

let priceUpdateKey = "com.ordr.priceUpdateKey"

Now write the function inside the cell class, and add the NSNotification method, sending your data in the userInfo parameter

func cellAddItemAction(sender: UIButton){

    var count = (String(self.itemQty.text!)).toInt()!
    totalPrice = (self.itemPriceLabel!.text! as NSString).doubleValue

    count += 1

    NSNotificationCenter.defaultCenter().postNotificationName(priceUpdateKey, object: nil, userInfo: ["totalPrice":totalPrice])

}

Then back in the viewController, add an observer for the NSNotification:

NSNotificationCenter.defaultCenter().addObserver(self, selector: "updatePrice:", name: priceUpdateKey, object: nil)

And finally write the function that the observer calls:

func updatePrice(sender: NSNotification) {

    let userInfo:Dictionary<String,Double!> = sender.userInfo as Dictionary<String,Double!>
    let messagePrice = userInfo["totalPrice"]
    let finalCalc = totalAmount + messagePrice!
    totalAmount = finalCalc

    totalPriceButton.setTitle("£\(totalAmount)0", forState: UIControlState.Normal)

}'

Note** I'm not claiming this is a good method, but it works for me, and if it helps you, perfect.