Use tags for tableView inside UIViewController to update Labels

Question

I added a table view to my UIViewController. then i added a label to my custom cell inside the table view. i tried to update labels inside the tableview by using tags. seems it does not working.

this is my code.

func tableView(tableView: UITableView, cellForRowAtIndexPath indexPath: NSIndexPath) -> UITableViewCell {
    let cell: UITableViewCell = self.tableView.dequeueReusableCellWithIdentifier("LineItemCell", forIndexPath: indexPath)
    let object = lineItemsObject[indexPath.row]
    //cell.textLabel?.text = object["quantity"]

    print(object["description"]!)

    if let descriptionLabel = cell.viewWithTag(500) as? UILabel {
        descriptionLabel.text = object["description"]
    }
    else
    {
        print("fail")
    }

    return cell
}

When i call the function always it does not read the tag and prints "fail". i have assigned correct tag value to my label also.

here i have attached a image of my label details in attribute inspector

Please help me the fix the issue.

Answer 1

Your cell is not knowing about your label inside (the one with 500 tag). You are not providing a custom cell, because of this line:

let cell: UITableViewCell = self.tableView.dequeueReusableCellWithIdentifier("LineItemCell", forIndexPath: indexPath)

This is a predefined cell. As of documentation you can have predefined cells or custom ones (obtained by subclassing UITableViewCell):

"When creating cells, you can customize them yourself or use one of several predefined styles. The predefined cell styles are the simplest option. With the predefined styles, the cell provides label and image subviews whose positions and styling are fixed. ... To set the text and images of the cell, use the textLabel, detailTextLabel, and imageView properties."

1. If you want to go predefined: If you want to just put the text onto cell use (I see this one is commented on first place).

   cell.textLabel?.text = object["quantity"]

2. Go custom

Extend UITableViewCell on a separate swift file. Do your bindings here and work with your storyboard in parallel. Assign the custom class to your cell. Also, change dequeue:

let cell: MyCustomTableViewCell = self.tableView.dequeueReusableCellWithIdentifier("LineItemCell", forIndexPath: indexPath) as! MyCustomTableViewCell

Answer 2

As @TheAppMentor said code looks fine. Make sure you entered correct cell identifier. Then make sure you connected your view controller to correct class (it's my common mistake). Also make sure that something else in this cell hasn't the same tag. You can also print all subviews to check what's inside.