Swift 3.0 How to Change a Button Title Using TableView Cells - ios

Question

I have a table view with subclassed table view cells. I have attached a button and hooked this up to the table view cell's VC. I want the button to say 'Add' upon loading, 'Subtract' when clicked and back to 'Add' when clicked again. But I am having trouble understanding how I can relate the row number with the state of the button.
VC with table view:
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! TVCell
cell.cellDelegate = self
if (searchActive) {
cell.textLabel?.text = filtered[indexPath.row]
} else {
cell.textLabel?.text = data[indexPath.row]
}
return cell
}
func didPressButton(cell: TVCell) {
guard let indexPath = self.tableView.indexPath(for: cell) else {
return
}
print("Button tapped on row \(indexPath.row)")
}
VC for table view cell:
protocol TVCellDelegate : class {
func didPressButton(cell: TVCell)
}
class TVCell: UITableViewCell {
#IBOutlet weak var addButton: UIButton!
weak var cellDelegate: TVCellDelegate?
override func prepareForReuse() {
super.prepareForReuse()
self.cellDelegate = nil
}
// connect the button from your cell with this method
#IBAction func buttonPressed(sender: UIButton) {
self.cellDelegate?.didPressButton(cell: self)
}
}

Answer 1

Store the buttons' state in your view controller and change the text after reusing and button pressing.
VC with TableView:
var isSubtracting = [IndexPath: Bool]()
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! TVCell
cell.cellDelegate = self
if isSubtracting[indexPath] ?? false {
cell.addButton.setTitle("Add", for: .normal)
} else {
cell.addButton.setTitle("Subtract", for: .normal)
}
cell.indexPath = indexPath
if(searchActive) {
cell.textLabel?.text = filtered[indexPath.row]
} else {
cell.textLabel?.text = data[indexPath.row]
}
return cell
}
func didPressButton(indexPath: IndexPath) {
guard let cell = tableView.cellForRow(at: indexPath) as? TVCell else {
return
}
if isSubtracting[indexPath] ?? false {
isSubtracting[indexPath] = false
cell.addButton.setTitle("Subtract", for: .normal)
} else {
isSubtracting[indexPath] = true
cell.addButton.setTitle("Add", for: .normal)
}
}
VC for table view cell:
protocol TVCellDelegate : class {
func didPressButton(indexPath: IndexPath)
}
class TVCell: UITableViewCell {
#IBOutlet weak var addButton: UIButton!
weak var cellDelegate: TVCellDelegate?
var indexPath: IndexPath!
override func prepareForReuse() {
super.prepareForReuse()
self.cellDelegate = nil
}
// connect the button from your cell with this method
#IBAction func buttonPressed(sender: UIButton) {
self.cellDelegate?.didPressButton(indexPath: indexPath)
}
}

Answer 2

You can add the title's for the states of buttons like this
func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
let cell = tableView.dequeueReusableCell(withIdentifier: "Cell", for: indexPath) as! TVCell
cell.cellDelegate = self
cell.indexPath = indexPath
cell.addButton.setTitle("Add",for: .normal)
cell.addButton.setTitle("Subtract",for: .selected)
if(searchActive) {
cell.textLabel?.text = filtered[indexPath.row]
} else {
cell.textLabel?.text = data[indexPath.row]
}
return cell
}
and tableViewCell
protocol TVCellDelegate : class {
func didPressButton(indexPath: IndexPath)
}
class TVCell: UITableViewCell {
#IBOutlet weak var addButton: UIButton!
weak var cellDelegate: TVCellDelegate?
var indexPath: IndexPath!
override func prepareForReuse() {
super.prepareForReuse()
self.cellDelegate = nil
}
// connect the button from your cell with this method
#IBAction func buttonPressed(sender: UIButton) {
if(sender.isSelected){
sender.isSelected = false
}else{
sender.isSelected = true
}
self.cellDelegate?.didPressButton(indexPath: indexPath)
}
}