La soluzione definitiva con ispirazione da SomaMan. Basta sottoclasse tutti i tuoi pulsanti personalizzati e si ottiene questo:

include: sull'animazione rubinetto e rilasciare e trascinare via.
//
// CustomFocusButton.swift
//
import UIKit
class CustomFocusButton: UIButton {
let focusedScaleFactor : CGFloat = 1.2
let focusedShadowRadius : CGFloat = 10
let focusedShadowOpacity : Float = 0.25
let shadowColor = UIColor.blackColor().CGColor
let shadowOffSetFocused = CGSizeMake(0, 27)
let animationDuration = 0.2
override func didUpdateFocusInContext(context: UIFocusUpdateContext, withAnimationCoordinator coordinator: UIFocusAnimationCoordinator)
{
coordinator.addCoordinatedAnimations({
if self.focused{
UIView.animateWithDuration(self.animationDuration, animations:{ [weak self]() -> Void in
guard let weakSelf = self else {return}
weakSelf.transform = CGAffineTransformMakeScale(weakSelf.focusedScaleFactor, weakSelf.focusedScaleFactor)
weakSelf.clipsToBounds = false
weakSelf.layer.shadowOpacity = weakSelf.focusedShadowOpacity
weakSelf.layer.shadowRadius = weakSelf.focusedShadowRadius
weakSelf.layer.shadowColor = weakSelf.shadowColor
weakSelf.layer.shadowOffset = weakSelf.shadowOffSetFocused
},completion:{ [weak self] finished in
guard let weakSelf = self else {return}
if !finished{
weakSelf.transform = CGAffineTransformMakeScale(weakSelf.focusedScaleFactor, weakSelf.focusedScaleFactor)
weakSelf.clipsToBounds = false
weakSelf.layer.shadowOpacity = weakSelf.focusedShadowOpacity
weakSelf.layer.shadowRadius = weakSelf.focusedShadowRadius
weakSelf.layer.shadowColor = weakSelf.shadowColor
weakSelf.layer.shadowOffset = weakSelf.shadowOffSetFocused
}
})
} else {
UIView.animateWithDuration(self.animationDuration, animations:{ [weak self]() -> Void in
guard let weakSelf = self else {return}
weakSelf.clipsToBounds = true
weakSelf.transform = CGAffineTransformIdentity
}, completion: {[weak self] finished in
guard let weakSelf = self else {return}
if !finished{
weakSelf.clipsToBounds = true
weakSelf.transform = CGAffineTransformIdentity
}
})
}
}, completion: nil)
}
override func pressesBegan(presses: Set<UIPress>, withEvent event: UIPressesEvent?) {
UIView.animateWithDuration(animationDuration, animations: { [weak self]() -> Void in
guard let weakSelf = self else {return}
weakSelf.transform = CGAffineTransformIdentity
weakSelf.layer.shadowOffset = CGSizeMake(0, 10);
})
}
override func pressesCancelled(presses: Set<UIPress>, withEvent event: UIPressesEvent?) {
if focused{
UIView.animateWithDuration(animationDuration, animations: { [weak self]() -> Void in
guard let weakSelf = self else {return}
weakSelf.transform = CGAffineTransformMakeScale(weakSelf.focusedScaleFactor, weakSelf.focusedScaleFactor)
weakSelf.layer.shadowOffset = weakSelf.shadowOffSetFocused
})
}
}
override func pressesEnded(presses: Set<UIPress>, withEvent event: UIPressesEvent?) {
if focused{
UIView.animateWithDuration(animationDuration, animations: {[weak self]() -> Void in
guard let weakSelf = self else {return}
weakSelf.transform = CGAffineTransformMakeScale(weakSelf.focusedScaleFactor, weakSelf.focusedScaleFactor)
weakSelf.layer.shadowOffset = weakSelf.shadowOffSetFocused
})
}
}
}
La ragione per questo è particolarmente frustrante è che se si aggiunge l'ombra di programmazione, si perde tutta la mezza fresco movimento rimbalzante. – livingtech
Un ingegnere Apple (nei forum dev) ha affermato che è possibile riprodurre il movimento utilizzando la nuova API 'UIMotionEffect': https://developer.apple.com/library/prerelease/tvos/documentation/UIKit/Reference/UIMotionEffect_class/index. html Non so come, ma potrei giocarci. – livingtech