How to add transition on UITapGestureRecognizer in Swift 3? - swift

Question

I'm trying to make the image view full screen when I click on the small image. But the image show very fast when I clicked on the image. Can I add some transition time to delay the full screen image showing?
#IBAction func uploadImgAction(_ sender: Any) {
let tapgesture = UITapGestureRecognizer(target: self, action: #selector(DeleteJobViewController.tap))
tapgesture.numberOfTapsRequired = 1
reasonImg.addGestureRecognizer(tapgesture)
}
func tap(){
print("tap")
let newImageView = UIImageView(image: reasonImg.image)
newImageView.frame = self.view.frame
newImageView.backgroundColor = .black
newImageView.contentMode = .scaleAspectFit
newImageView.isUserInteractionEnabled = true
let tap = UITapGestureRecognizer(target: self, action: #selector(dismissFullscreenImage))
newImageView.addGestureRecognizer(tap)
self.view.addSubview(newImageView)
}
func dismissFullscreenImage(sender: UITapGestureRecognizer) {
sender.view?.alpha = 1
UIView.animate(withDuration: 1.5, animations: {
sender.view?.alpha = 0
sender.view?.removeFromSuperview()
})
}

Answer 1

Try replacing the self.view.addSubview(newImageView) line with:
DispatchQueue.main.async {
UIView.transition(with: self.view, duration:0.6, options: UIViewAnimationOptions.showHideTransitionViews, animations: {
self.view.addSubview(self.newImageView)
}, completion: nil)
}
You can also try setting newImageView.alpha = 0 before running this code:
UIView.animate(withDuration: 1.5, animations: {
self.newImageView.alpha = 1.0
})
For animating the disappear effect, in the code above, replace the addSubview statement with newImageView.removeFromSuperview().
And similarly you can set this after you have set the newImageView.alpha = 1:
func dismissFullscreenImage(sender: UITapGestureRecognizer) {
UIView.animate(withDuration: 1.5, animations: {
self.newImageView.alpha = 0
})
}
EDIT:
Please add newImageView as a property at the top of your view controller.
Then in your tap function set this instead of let newImageView:
self.newImageView = UIImageView(image: reasonImg.image)
Now if you run the code it should compile.

Answer 2

yourImageView.alpha = 0
*your addSubview in the middle
UIView.animate(withDuration: 0.5, animations: {
yourImageView.alpha = 1
})
First set your image to be invisible, then animate (in my example for 0.5 sec) to be visible.

Answer 3

func tap() {
print("tap")
let newImageView = UIImageView(image: reasonImg.image)
newImageView.frame = self.view.frame
newImageView.transform = CGAffineTransform.init(scaleX: 0.0, y: 0.0)
newImageView.backgroundColor = .black
newImageView.contentMode = .scaleAspectFit
newImageView.isUserInteractionEnabled = true
let tap = UITapGestureRecognizer(target: self, action: #selector(dismissFullscreenImage))
newImageView.addGestureRecognizer(tap)
self.view.addSubview(newImageView)
UIView.animate(withDuration: 0.5, animations: {
newImageView.transform = CGAffineTransform.init(scaleX: 1.0, y: 1.0)
})
}