My app is in prototype stage of development. Some sliders do not have any action assigned to them either through storyboard or programmatically.
I need to display an alert when slider drag stops during testing. Can this be done through an extension of UISlider?
How can I assign a default action to UISlider when the drag ends to show an alert unless another action is assigned via interface builder or programmatically?
class ViewController: UIViewController {
override func viewDidLoad() {
super.viewDidLoad()
self.checkButtonAction()
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
}
}
extension UIViewController{
func checkButtonAction(){
for view in self.view.subviews as [UIView] {
if let btn = view as? UISlider {
if (btn.allTargets.isEmpty){
btn.add(for: .allTouchEvents, {
if (!btn.isTracking){
let alert = UIAlertController(title: "Test 3", message:"No selector", preferredStyle: UIAlertControllerStyle.alert)
// add an action (button)
alert.addAction(UIAlertAction(title: "OK", style: UIAlertActionStyle.default, handler: nil))
// show the alert
self.present(alert, animated: true, completion: nil)
}
})
}
}
}
}
}
class ClosureSleeve {
let closure: ()->()
init (_ closure: @escaping ()->()) {
self.closure = closure
}
@objc func invoke () {
closure()
}
}
extension UIControl {
func add (for controlEvents: UIControlEvents, _ closure: @escaping ()->()) {
let sleeve = ClosureSleeve(closure)
addTarget(sleeve, action: #selector(ClosureSleeve.invoke), for: controlEvents)
objc_setAssociatedObject(self, String(format: "[%d]", arc4random()), sleeve, objc_AssociationPolicy.OBJC_ASSOCIATION_RETAIN)
}
}
Please check this modified Answer.