Blinking effect on UILabel

Question

I have a UILabel with background color as grey.

I want a blinking effect on this label like it should become a little white & then become gray and it should keep

Answer 1

Tweaking Krishnabhadra Answer to give a better blink effect

Declare a Class variable bool blinkStatus;

And paste code given below

NSTimer *yourtimer = [NSTimer scheduledTimerWithTimeInterval:(NSTimeInterval)(10.0 / 60.0)  target:self selector:@selector(blink) userInfo:nil repeats:TRUE];
    blinkStatus = FALSE;

-(void)blink{
    if(blinkStatus == FALSE){
        yourLabel.hidden=NO;
        blinkStatus = TRUE;
    }else {
        yourLabel.hidden=YES;
        blinkStatus = FALSE;
    }
}

Answer 2

My swift version based on Flex Elektro Deimling's answer:

private func startTimeBlinkAnimation(start: Bool) {
    if start {
        timeContainerView.alpha = 1
        UIView.animateWithDuration(0.6, delay: 0.3, options:[.Repeat, .Autoreverse], animations: { _ in
            self.timeContainerView.alpha = 0
        }, completion: nil)
    }
    else {
        timeContainerView.alpha = 1
        timeContainerView.layer.removeAllAnimations()
    }
}

Answer 3

Use NSTimer

NSTimer *timer = [NSTimer 
                      scheduledTimerWithTimeInterval:(NSTimeInterval)(1.0)
                            target:self 
                             selector:@selector(blink) 
                             userInfo:nil 
                             repeats:TRUE];
BOOL blinkStatus = NO;

in your blink function

-(void)blink{
   if(blinkStatus == NO){
      yourLabel.backgroundColor = [UIColor whiteColor];
     blinkStatus = YES;
   }else {
      yourLabel.backgroundColor = [UIColor grayColor];
      blinkStatus = NO;
   }
}

Answer 4

Swift 3

extension UILabel {

    func startBlink() {
        UIView.animate(withDuration: 0.8,
              delay:0.0,
              options:[.allowUserInteraction, .curveEaseInOut, .autoreverse, .repeat],
              animations: { self.alpha = 0 }, 
              completion: nil)
    }

    func stopBlink() {
        layer.removeAllAnimations()
        alpha = 1
    }
}

Answer 5

You can simply make an extension to the UILabel class that will support the blinking effect. I don't think using a timer is a right approach since you won't have any fade effect.

Here is the Swift way to do this:

extension UILabel {
    func blink() {
        self.alpha = 0.0;
        UIView.animateWithDuration(0.8, //Time duration you want,
                            delay: 0.0,
                          options: [.CurveEaseInOut, .Autoreverse, .Repeat],
                       animations: { [weak self] in self?.alpha = 1.0 },
                       completion: { [weak self] _ in self?.alpha = 0.0 })
    }
}

Swift 3:

extension UILabel {
    func blink() {
        self.alpha = 0.0;
        UIView.animate(withDuration: 0.8, //Time duration you want,
            delay: 0.0,
            options: [.curveEaseInOut, .autoreverse, .repeat],
            animations: { [weak self] in self?.alpha = 1.0 },
            completion: { [weak self] _ in self?.alpha = 0.0 })
    }
}

EDIT Swift 3: Works for almost any view

extension UIView {
    func blink() {
        self.alpha = 0.0;
        UIView.animate(withDuration: 0.8, //Time duration you want,
            delay: 0.0,
            options: [.curveEaseInOut, .autoreverse, .repeat],
            animations: { [weak self] in self?.alpha = 1.0 },
            completion: { [weak self] _ in self?.alpha = 0.0 })
    }
}

Answer 6

Got stuck when trying with swift and using multiple options but this seems to work nicely:

self.cursorLabel.alpha = 1
UIView.animate(withDuration: 0.7, delay: 0.0, options: [.repeat, .autoreverse, .curveEaseInOut], animations: {
    self.cursorLabel.alpha = 0
}, completion: nil)