I've tried every syntax variation that I can, but the completion handler always activates before the end of the animation. I think I'm supposed to replace Bool with something else?
UIView.transition(with: swipeForPicturesIndicator,
duration: 1,
options: .curveEaseIn,
animations: {
self.swipeForPicturesIndicator.alpha = 0
},
completion: { (Bool) -> Void in
self.swipeForPicturesIndicator.isHidden = true
self.swipeForPicturesIndicator.alpha = 0.8
})
The Bool value indicates wether the animation was finished when the completion block was called. If that value is false it means your animation was interrupted.
You should use probably animate instead of transition
UIView.animate(withDuration: 1,
delay: 0,
options: .curveEaseIn,
animations: {
self.swipeForPicturesIndicator.alpha = 0
}) { (completed) in
/* Optionally check if animation finished */
self.swipeForPicturesIndicator.isHidden = true
self.swipeForPicturesIndicator.alpha = 0.8
}
Try this
self.swipeForPicturesIndicator.alpha = 0
UIView.transition(with: swipeForPicturesIndicator,
duration: 1,
options: .curveEaseIn,
animations: {
self.swipeForPicturesIndicator.alpha = 0.8
},
completion: nil)
You may want to use animate instead of transition:
UIView.animate(withDuration: 1, delay: 0, options: .curveEaseIn, animations: {
self.swipeForPicturesIndicator.alpha = 0
}) { (success) in
self.swipeForPicturesIndicator.isHidden = true
self.swipeForPicturesIndicator.alpha = 0.8
}
My code below is a button that when hit applies animation. Right now there are two animations. I would like to do a sequence the animations meaning have the 2nd animation not start until the first animation has completed.
var speed: CGFloat = 5.3 // speed in seconds
#IBAction func press(_ sender: Any) {
self.theTextView.resignFirstResponder()
UIView.animate(withDuration: TimeInterval(speed), animations: {
////1st action[
self.theTextView.contentOffset = .zero
self.theTextView.setContentOffset(.zero, animated: true)]
/////2nd action[
self.theTextView.contentOffset = CGPoint(x: 0, y: self.theTextView.contentSize.height)]
}, completion: nil)
}}
The easiest way of doing that would be using the completion block of the animate(withDuration:animations:completion:) method. The completion block is executed when the animation sequence ends. In your case, it would look like this :
UIView.animate(withDuration: 6.0, animations: {
// First animation goes here
self.theTextView.contentOffset = CGPoint.zero
}, completion: { (finished) in
// This completion block is called when the first animation is done.
// Make sure the animation was not interrupted/cancelled :
guard finished else {
return
}
UIView.animate(withDuration: 1.0, animations: {
// And the second animation goes here
self.theTextView.contentOffset = CGPoint(x: 0, y: self.theTextView.contentSize.height)
})
})
There is also convenient way to make sequence of concurrent animations by using animateKeyframes:
UIView.animateKeyframes(withDuration: 1, delay: 0, options: .calculationModeCubic, animations: {
UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 0.3, animations: {
self.someView.alpha = 0.5
self.view.layoutIfNeeded()
})
//second animation
UIView.addKeyframe(withRelativeStartTime: 0.4, relativeDuration: 0.3, animations: {
self.someView.alpha = 1
self.view.layoutIfNeeded()
})
}, completion: { (finish) in
// Do something on animation complete
})
I have a label that is initially positioned at the center of the screen. It currently transitions from the the center to the right end of the screen then autoreverses back to its position. I'd like to have it begin another animateWithDuration so that it continues from the center return to the left position of the screen then autoreverse back to the position and sequentially loop from there on after.
I have already attempted and successfully made the first half work but I'm not sure how to continue to the second portion where it begins the center->left transition and loop.
Swift 2.0 Code:
func animateRight()
{
UIView.animateWithDuration(1.0, delay: 0.0, options: [ .Autoreverse, .CurveEaseInOut], animations: {
label.center.x = self.view.frame.width/2
}, completion: { finished in
if finished {
label.frame.origin.x = 0.0
animateLeft()
}
})
}
func animateLeft()
{
UIView.animateWithDuration(1.0, delay: 0.0, options: [ .Autoreverse, .CurveEaseInOut], animations: {
label.frame.origin.x = (self.view.frame.width/2) * -1
}, completion: { finished in
if finished {
label.center.x = self.view.frame.width/2
animateRight()
}
})
}
// Start process
animateRight()
You should call the same animate with duration method you create for animating to right and call in completion. Something like this:
func animateRight()
{
UIView.animate(withDuration: 1.0, delay: 0.0, options: [], animations: {
self.label.center.x = self.view.frame.width
}, completion: { finished in
if finished {
self.animateLeft()
}
})
}
func animateLeft()
{
UIView.animate(withDuration: 2.0, delay: 0.0, options: [ .autoreverse, .repeat, .curveEaseInOut, .beginFromCurrentState], animations: {
self.label.frame.origin.x = 0.0
}, completion: nil)
}
Call defaultSetup to start
When animationRight end, it will call animationLeft
When animationLeft end, it will call animationRight again to run animation loop
Here is the code:
func defaultSetup(){
self.animationRight()
}
func animationRight(){
let transform = CGAffineTransform(scaleX: 1.05, y: 1.05).rotated(by: .pi/180)
UIView.animate(withDuration: 3.0, delay: 0, usingSpringWithDamping: 0.2, initialSpringVelocity: 3.0, options: [.allowUserInteraction, .repeat], animations: { [weak self] in
guard let `self` = self else { return }
self.vRight.transform = transform
}, completion: { [weak self] (done) in
guard let `self` = self else { return }
self.vRight.transform = .identity
self.animationLeft()
})
}
func animationLeft(){
let transform = CGAffineTransform(scaleX: 1.05, y: 1.05).rotated(by: .pi/180)
UIView.animate(withDuration: 3.0, delay: 0, usingSpringWithDamping: 0.2, initialSpringVelocity: 3.0, options: [.allowUserInteraction], animations: { [weak self] in
guard let `self` = self else { return }
self.vLeft.transform = transform
}, completion: { [weak self] (done) in
guard let `self` = self else { return }
self.vLeft.transform = .identity
self.animationRight()
})
}
I am trying to toggle the visibility of a UILabel based on a Tap Gesture on an UIImageView. The code that performs the toggling is as follows:
func imageTapped(img: UIImageView) {
print(photoTitle.hidden)
if (photoTitle.hidden) {
UIView.animateWithDuration(0.5, delay: 0, options: UIViewAnimationOptions.CurveEaseInOut, animations: {
self.photoTitle.alpha = 1
}, completion: nil)
}
else {
UIView.animateWithDuration(0.5, delay: 0, options: UIViewAnimationOptions.CurveEaseInOut, animations: {
self.photoTitle.alpha = 0
}, completion: nil)
}
self.photoTitle.hidden = !self.photoTitle.hidden
}
The issue with this is that it seems to ignore the animation on the second tap i.e. to hide the UILabel again. It just becomes invisible instead of animating gradually. In the viewdDidLoad(), I initialize the photoTitle.hidden = true to be invisible initially.
Any glaring mistakes?
You need to move self.photoTitle.hidden = true into the completion block of your else condition
hidden doesn't work on this animation, you can instead of alpha
Just try to change the function like this
Swift 2
func imageTapped(img: UIImageView) {
print(photoTitle.hidden)
UIView.animateWithDuration(0.5, delay: 0, options: UIViewAnimationOptions.CurveEaseInOut, animations: {
self.photoTitle.alpha = self.photoTitle.alpha < 0.5 ? 1.0 : 0.0
}, completion: nil)
}
Swift 3, 4, 5
func imageTapped(img: UIImageView) {
print(photoTitle.hidden)
UIView.animate(withDuration: 0.5, delay: 0, options: UIView.AnimationOptions.curveEaseInOut, animations: {
self.photoTitle.alpha = self.photoTitle.alpha < 0.5 ? 1.0 : 0.0
}, completion: nil)
}
I am trying to change a button's color (just a flash/blink) to green when a scan is correct and red when there's a problem. I am able to do this with a view like so
func flashBG(){
UIView.animateWithDuration(0.7, animations: {
self.view.backgroundColor = UIColor.greenColor()
})
}
But with a button it stays green
func flashBtn(){
UIButton.animateWithDuration(0.5, animations: {
self.buttonScan.backgroundColor = UIColor.greenColor()
})
}
I have created the button by code
func setupScanButton() {
let X_Co = (self.view.frame.size.width - 100)/2
let Y_Co = (self.viewForLayer.frame.size.height + 36/2)
buttonScan.frame = CGRectMake(X_Co,Y_Co,100,100)
buttonScan.layer.borderColor = UIColor.whiteColor().CGColor
buttonScan.layer.borderWidth = 2
buttonScan.layer.cornerRadius = 50
buttonScan.setTitle("Scan", forState: .Normal)
buttonScan.backgroundColor = UIColor.blueColor()
buttonScan.addTarget(self, action: "buttonScanAction", forControlEvents: .TouchUpInside)
buttonScan.setTitleColor(UIColor(red:255/255, green: 255/255, blue:255/255, alpha: 1), forState: UIControlState.Normal)
self.view.addSubview(buttonScan)
}
Should i call setupScanButton() again?
This should work in Swift 4
extension UIView{
func blink() {
self.alpha = 0.2
UIView.animate(withDuration: 1, delay: 0.0, options: [.curveLinear, .repeat, .autoreverse], animations: {self.alpha = 1.0}, completion: nil)
}
}
This will start and stop a flashing button onClick, if you only want to flash the button immediately just use the first statement.
var flashing = false
#IBAction func btnFlash_Clicked(sender: AnyObject) {
if !flashing{
self.buttonScan.alpha = 1.0
UIView.animateWithDuration(0.5, delay: 0.0, options: [.CurveEaseInOut, .Repeat, .Autoreverse, .AllowUserInteraction], animations: {() -> Void in
self.buttonScan.alpha = 0.0
}, completion: {(finished: Bool) -> Void in
})
flashing = true
}
else{
UIView.animateWithDuration(0.1, delay: 0.0, options: [.CurveEaseInOut, .BeginFromCurrentState], animations: {() -> Void in
self.buttonScan.alpha = 1.0
}, completion: {(finished: Bool) -> Void in
})
}
}
Swift 5.x version
An updated version with extension.
extension UIView {
func blink(duration: TimeInterval = 0.5, delay: TimeInterval = 0.0, alpha: CGFloat = 0.0) {
UIView.animate(withDuration: duration, delay: delay, options: [.curveEaseInOut, .repeat, .autoreverse], animations: {
self.alpha = alpha
})
}
}
To call the function:
button.blink() // without parameters
button.blink(duration: 1, delay: 0.1, alpha: 0.2) // with parameters
I hope that will solve your problem.
buttonScan.alpha = 1.0
UIView.animate(withDuration: 1.0, delay: 1.0, options: UIView.AnimationOptions.curveEaseOut, animations: {
buttonScan.alpha = 0.0
}, completion: nil)
Swift 4:
I've maked an extension with some useful options:
extension UIButton {
open override func hitTest(_ point: CGPoint, with event: UIEvent?) -> UIView? {
return self.bounds.contains(point) ? self : nil
}
func blink(enabled: Bool = true, duration: CFTimeInterval = 1.0, stopAfter: CFTimeInterval = 0.0 ) {
enabled ? (UIView.animate(withDuration: duration, //Time duration you want,
delay: 0.0,
options: [.curveEaseInOut, .autoreverse, .repeat],
animations: { [weak self] in self?.alpha = 0.0 },
completion: { [weak self] _ in self?.alpha = 1.0 })) : self.layer.removeAllAnimations()
if !stopAfter.isEqual(to: 0.0) && enabled {
DispatchQueue.main.asyncAfter(deadline: .now() + stopAfter) { [weak self] in
self?.layer.removeAllAnimations()
}
}
}
}
First of all, I've overrided the hittest function to enabling the touch also when the button have the alpha equals to 0.0 (transparent) during the animation.
Then , all input vars have a default value so you can launch the blink() method without parameters
I've introduced also the enabled parameter to start or stop the animations on your button.
Finally, if you want you can stop animation after a specific time with the stopAfter parameter.
Usage:
yourButton.blink() // infinite blink effect with the default duration of 1 second
yourButton.blink(enabled:false) // stop the animation
yourButton.blink(duration: 2.0) // slowly the animation to 2 seconds
yourButton.blink(stopAfter:5.0) // the animation stops after 5 seconds.
Typical uses:
yourButton.blink(duration: 1.5, stopAfter:10.0)
// your code..
yourButton.blink()
// other code..
yourButton.blink(enabled:false)
You can try something like this:
extension UIView {
func blink() {
UIView.animateWithDuration(0.5, //Time duration you want,
delay: 0.0,
options: [.CurveEaseInOut, .Autoreverse, .Repeat],
animations: { [weak self] in self?.alpha = 0.0 },
completion: { [weak self] _ in self?.alpha = 1.0 })
dispatch_after(dispatch_time(DISPATCH_TIME_NOW,Int64(2 * NSEC_PER_SEC)),dispatch_get_main_queue()){
[weak self] in
self?.layer.removeAllAnimations()
}
}
}
//MARK : Usage
yourButton.flash()
extension UIButton {
func flash() {
let flash = CABasicAnimation(keyPath: "opacity")
flash.duration = 0.5
flash.fromValue = 1
flash.toValue = 0.1
flash.timingFunction = CAMediaTimingFunction(name: CAMediaTimingFunctionName.easeInEaseOut)
flash.autoreverses = true
flash.repeatCount = 3
layer.add(flash, forKey: nil)
}
}
Swift 3.0
func btnFlash_Clicked(sender: AnyObject) {
if !flashing{
callButton.alpha = 1.0
UIView.animate(withDuration: 0.5, delay: 0.0, options: [.allowUserInteraction], animations: {() -> Void in
callButton.alpha = 0.5
}, completion: {(finished: Bool) -> Void in
})
flashing = true
}
else{
flashing = false
callButton.alpha = 0.5
UIView.animate(withDuration: 0.5, delay: 0.0, options: [.allowUserInteraction], animations: {() -> Void in
callButton.alpha = 1.0
}, completion: {(finished: Bool) -> Void in
})
}
}
with UIViewPropertyAnimator and Swift 5
UIViewPropertyAnimator.runningPropertyAnimator(withDuration: 1, delay: 0, options: [.curveLinear,.repeat], animations: {
UIView.setAnimationRepeatCount(3000)
self.buttonScan.alpha = 0.0
}, completion: {_ in })
Swift 3.0
func animateFlash() {
flashView.alpha = 0
flashView.isHidden = false
UIView.animate(withDuration: 0.3, animations: { flashView.alpha = 1.0 }) { finished in flashView.isHidden = true }
}
This UIView extension "blinks" a view and changes the background colour:
/**
Blinks a view with a given duration and optional color.
- Parameter duration: The duration of the blink.
- Parameter color: The color of the blink.
*/
public func blink(withDuration duration: Double = 0.25, color: UIColor? = nil) {
alpha = 0.2
UIView.animate(withDuration: duration, delay: 0.0, options: [.curveEaseInOut], animations: {
self.alpha = 1.0
})
guard let newBackgroundColor = color else { return }
let oldBackgroundColor = backgroundColor
UIView.animate(withDuration: duration, delay: 0.0, options: [.curveEaseInOut], animations: {
self.backgroundColor = newBackgroundColor
self.backgroundColor = oldBackgroundColor
})
}
You would then use as follows:
buttonScan.blink(color: .green)
myButton.alpha = 0.7
UIView.animate(withDuration: 0.3,
delay: 1.0,
options: [UIView.AnimationOptions.curveLinear, UIView.AnimationOptions.repeat, UIView.AnimationOptions.autoreverse],
animations: { myButton.alpha = 1.0 },
completion: nil)
Another smoothly animating version for Swift 5:
public extension UIView {
func blink(duration: TimeInterval) {
let initialAlpha: CGFloat = 1
let finalAlpha: CGFloat = 0.2
alpha = initialAlpha
UIView.animateKeyframes(withDuration: duration, delay: 0, options: .beginFromCurrentState) {
UIView.addKeyframe(withRelativeStartTime: 0, relativeDuration: 0.5) {
self.alpha = finalAlpha
}
UIView.addKeyframe(withRelativeStartTime: 0.5, relativeDuration: 0.5) {
self.alpha = initialAlpha
}
}
}
}