create a if statement where only one button at a time can have a border - swift

Question

I want my swift code to use a if statement or another sequence to only display a border on one of the buttons if click at a time. So a border can only be seen on one button at a time that button would be the last one pressed. I know I could say layer.border with 0 on each button that should be selected but I want to see if there is a more efficient way to do this.
import UIKit
class ViewController: UIViewController {
var ba = UIButton()
var bb = UIButton()
var bc = UIButton()
override func viewDidLoad() {
super.viewDidLoad()
[ba,bb,bc].forEach {
$0.translatesAutoresizingMaskIntoConstraints = false
view.addSubview($0)
}
ba.frame = CGRect(x: 0, y: 0, width: 100, height: 100)
bb.frame = CGRect(x: 100, y: 0, width: 100, height: 100)
bc.frame = CGRect(x: 200, y: 0, width: 100, height: 100)
ba.backgroundColor = .blue
bb.backgroundColor = .orange
bc.backgroundColor = .darkGray
ba.addTarget(self, action: #selector(pressa), for: .touchDown)
bb.addTarget(self, action: #selector(pressb), for: .touchDown)
bc.addTarget(self, action: #selector(pressc), for: .touchDown)
}
#objc func pressa(){
ba.layer.borderWidth = 2
}
#objc func pressb(){
bb.layer.borderWidth = 2
}
#objc func pressc(){
bc.layer.borderWidth = 2
}
}

Answer 1

you can add target to all buttons at the forEach and be only one method as #Sh_Khan mention
import UIKit
class ViewController: UIViewController {
var ba = UIButton()
var bb = UIButton()
var bc = UIButton()
override func viewDidLoad() {
super.viewDidLoad()
[ba,bb,bc].forEach {
$0.translatesAutoresizingMaskIntoConstraints = false
view.addSubview($0)
$0.addTarget(self, action: #selector(pressAll(_:)), for: .touchDown)
}
ba.frame = CGRect(x: 0, y: 0, width: 100, height: 100)
bb.frame = CGRect(x: 100, y: 0, width: 100, height: 100)
bc.frame = CGRect(x: 200, y: 0, width: 100, height: 100)
ba.backgroundColor = .blue
bb.backgroundColor = .orange
bc.backgroundColor = .darkGray
}
#objc func pressAll(_ sender:UIButton) {
[ba,bb,bc].forEach { $0.layer.borderWidth = 0 } // reset all
sender.layer.borderWidth = 2
}
}

Answer 2

See how you have used an array in [ba,bb,bc].forEach { ... } to reduce code duplication? Using arrays is the key. Rather than putting the three buttons in an array inline like that, create a property instead:
var buttons: [UIButton]!
override func viewDidLoad() {
super.viewDidLoad()
buttons = [ba,bb,bc]
buttons.forEach {
$0.translatesAutoresizingMaskIntoConstraints = false
view.addSubview($0)
$0.addTarget(self, action: #selector(buttonPressed), for: .touchDown)
}
...
}
I have used the same selector buttonPressed for all three buttons. buttonPressed can accept a parameter of type UIButton, that tells us which button is pressed:
#objc func buttonPressed(_ sender: UIButton) {
buttons.forEach { ba.layer.borderWidth = 0 } // deselect all buttons first...
sender.layer.borderWidth = 2 // select the tapped button
}
If you have more than 3 buttons to manage, I suggest you don't use UIButtons at all. You should use a UICollectionView. (Learn how to use them) This view will handle the selection for you. It also allows scrolling when there's not enough space to show all the buttons. You just need to create a custom UICollectionViewCell and override its isSelected property:
override var isSelected: Bool {
didSet {
if isSelected {
self.layer.borderWidth = 2
} else {
self.layer.borderWidth = 0
}
}
}

Answer 3

It could be 1 method like this
[ba,bb,bc].forEach { $0.addTarget(self, action: #selector(pressAll(_:)), for: .touchDown) }
}
#objc func pressAll(_ sender:UIButton) {
[ba,bb,bc].forEach { $0.layer.borderWidth = 0 } // reset all
sender.layer.borderWidth = 2
}