Swift 4 & Swift 5:
You need to add target for that button.
myButton.addTarget(self, action: #selector(connected(sender:)), for: .touchUpInside)
And of course you need to set tag of that button since you are using it.
myButton.tag = indexPath.row
You can achieve this by subclassing UITableViewCell. Use it in interface builder, drop a button on that cell, connect it via outlet and there you go.
To get the tag in the connected function:
@objc func connected(sender: UIButton){
let buttonTag = sender.tag
}