Custom transition - ios

Question

I have a navigation controller, and inside of that navigation controller I have a home screen, from the home screen I click a button which goes to another screen.
But the standard show animation when using a navigation controller is that it slides from the side, but what I want to do is that the view controller slides up from bottom of the screen and creates a sort of bouncing animation when it reaches the top.

Answer 1

Anyone who wanted to use custom transition two things to remember UIViewControllerAnimatedTransitioning and UIViewControllerTransitioningDelegate protocols. Now conform UIViewControllerAnimatedTransitioning inside your customclass inheriting from NSObject
import UIKit
class CustomPushAnimation: NSObject, UIViewControllerAnimatedTransitioning {
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
return 0.2
}
func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
let containerVw = transitionContext.containerView
let fromViewController = transitionContext.viewController(forKey: .from)
let toViewController = transitionContext.viewController(forKey: .to)
guard let fromVc = fromViewController, let toVc = toViewController else { return }
let finalFrame = transitionContext.finalFrame(for: toVc)
//For different animation you can play around this line by changing frame
toVc.view.frame = finalFrame.offsetBy(dx: 0, dy: finalFrame.size.height/2)
containerVw.addSubview(toVc.view)
UIView.animate(withDuration: transitionDuration(using: transitionContext), animations: {
toVc.view.frame = finalFrame
fromVc.view.alpha = 0.5
}, completion: {(finished) in
transitionContext.completeTransition(finished)
fromVc.view.alpha = 1.0
})
}
}
The above method will take care of the animation. After that create
the above object and use inside yourViewController class
import UIKit
class YourViewController: UIViewController {
lazy var customPushAnimation: CustomPushAnimation = {
return CustomPushAnimation()
}()
func openViewControler() {
}let vc =//Assuming your view controller which you want to open
let navigationController = UINavigationController(rootViewController: vc)
//Set transitioningDelegate to invoke protocol method
navigationController.transitioningDelegate = self
present(navigationController, animated: true, completion: nil)
}
Note: In order to see the animation. Never set animation flag to false
while presenting the ViewController. Otherwise your animation will
never work.
Lastly implement the UIViewControllerTransitioningDelegate protocol method inside YourViewcontroller class
extension YourViewController: UIViewControllerTransitioningDelegate {
func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
return customPushAnimation
}
Whenever you present the viewcontroller above protocol method will
called and your animation magic will appear.