Animate UILabel text between two numbers?

I found a great engine for tweening values with a variety of different timing functions called PRTween. Install the classes and create some code along these lines:

- (IBAction)tweenValue
{
    [[PRTween sharedInstance] removeTweenOperation:activeTweenOperation];
    PRTweenPeriod *period = [PRTweenPeriod periodWithStartValue:0.0 endValue:100.0 duration:1.0];
    activeTweenOperation = [[PRTween sharedInstance] addTweenPeriod:period
                                                             target:self
                                                           selector:@selector(update:)
                                                     timingFunction:&PRTweenTimingFunctionCircOut];
}

- (void)update:(PRTweenPeriod*)period
{
    self.animatingView.center = CGPointMake(period.tweenedValue + 100.0, 200.0);
    self.valueLabel.text = [NSString stringWithFormat:@"%.2f", period.tweenedValue];
}

Works a treat for me. :)

You can use the automatic transitions. It's working perfectly well :

// Add transition (must be called after myLabel has been displayed)
 CATransition *animation = [CATransition animation];
animation.duration = 1.0;
animation.type = kCATransitionFade;
animation.timingFunction = [CAMediaTimingFunction functionWithName:kCAMediaTimingFunctionEaseInEaseOut];
[myLabel.layer addAnimation:animation forKey:@"changeTextTransition"];

// Change the text
myLabel.text = newText;

This code works if myLabel is already displayed. If not myLabel.layer will be nil and the animation will not be added to the object.

---

in Swift 4 that would be:

let animation: CATransition = CATransition()
animation.duration = 1.0
animation.type = kCATransitionFade
animation.timingFunction = CAMediaTimingFunction(name: kCAMediaTimingFunctionEaseInEaseOut)
myLabel.layer.add(animation, forKey: "changeTextTransition")

It works well!

Objective-C

[UIView transitionWithView:self.label 
                  duration:.5f 
                   options:UIViewAnimationOptionCurveEaseInOut | 
                           UIViewAnimationOptionTransitionCrossDissolve 
                animations:^{

    self.label.text = rand() % 2 ? @"111!" : @"42";

} completion:nil];

Swift 2

UIView.transitionWithView(label, duration: 0.25, options: [.CurveEaseInOut, .TransitionCrossDissolve], animations: {
    self.label.text = (arc4random() % 2 == 0) ? "111" : "222"
}, completion: nil)

Swift 3, 4, 5

UIView.transition(with: label, duration: 0.25, options: [.curveEaseInOut, .transitionCrossDissolve], animations: {
    self.label.text = (arc4random() % 2 == 0) ? "111" : "222"
}, completion: nil)