UILabel is not appearing in delayed sequence as expected - ios

Question

I want to make my UILabels appear in a delayed sequence. Thus one after another.
The code below works when I make them fade in using the alpha value but it doesn't do what I want it to do when I use the .hidden property of the UILabels.
The code makes my UILabels appear at all the same time instead of sum1TimeLabel first after 5 seconds, sum2TimeLabel second after 30 seconds and finally sum3TimeLabel third after 60 seconds. What am I doing wrong?
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
UIView.animateWithDuration(5.0, animations: {
self.sum1TimeLabel!.hidden = false;
})
UIView.animateWithDuration(30.0, animations: {
self.sum2TimeLabel!.hidden = false;
})
UIView.animateWithDuration(60.0, animations: {
self.sum3TimeLabel!.hidden = false;
})
}

Answer 1

As explained by SO user #matt in this answer, you can simply create a delay function with Grand Central Dispatch instead of using animateWithDuration, as animateWithDuration is usually meant for animating things over a period of time, and since the value you are animating is a Bool, it can't animate it.
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
delay(5.0) {
self.sum1TimeLabel?.hidden = false
}
delay(30.0) {
self.sum2TimeLabel?.hidden = false
}
delay(60.0) {
self.sum3TimeLabel?.hidden = false
}
}
func delay(delay:Double, closure:()->()) {
dispatch_after(
dispatch_time(
DISPATCH_TIME_NOW,
Int64(delay * Double(NSEC_PER_SEC))
),
dispatch_get_main_queue(), closure)
}

Answer 2

// Try this
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(animated)
self.sum1TimeLabel!.hidden = true;
self.sum2TimeLabel!.hidden = true;
self.sum3TimeLabel!.hidden = true;
UIView.animateWithDuration(5.0, animations: {
}, completion: {
self.sum1TimeLabel!.hidden = false;
})
UIView.animateWithDuration(30.0, animations: {
}, completion: {
self.sum2TimeLabel!.hidden = false;
})
UIView.animateWithDuration(60.0, animations: {
}, completion: {
self.sum3TimeLabel!.hidden = false;
})
}

Answer 3

class ViewController: UIViewController {
#IBOutlet weak var label1: UILabel!
#IBOutlet weak var label2: UILabel!
#IBOutlet weak var label3: UILabel!
override func viewDidLoad() {
super.viewDidLoad()
label1.alpha = 0
label2.alpha = 0
label3.alpha = 0
UIView.animateWithDuration(5.0, animations: { () -> Void in
print("animation on label1")
self.label1.alpha = 0.2
}) { (b) -> Void in
print("complete on label1")
self.label1.alpha = 1
UIView.animateWithDuration(5.0, animations: { () -> Void in
print("animation on label2")
self.label2.alpha = 0.2
}, completion: { (b) -> Void in
print("complete on label2")
self.label2.alpha = 1
UIView.animateWithDuration(5.0, animations: { () -> Void in
print("animation on label3")
self.label3.alpha = 0.2
}, completion: { (b) -> Void in
print("complete on label3")
self.label3.alpha = 1
})
})
}
// Do any additional setup after loading the view, typically from a nib.
}
override func didReceiveMemoryWarning() {
super.didReceiveMemoryWarning()
// Dispose of any resources that can be recreated.
}
}
You are NOT able to animate hidden property. there is two states only. how to change hidden continuously with time? instead you can animate alpha :-). try change the alpha value inside animation block to 0, or to 1.