我正在以模糊背景效果模式呈现视图控制器. iOS 10 / XCode 8引入了我的动画问题.这是演示代码：
let modalVC = ModalViewController(nibName: "ModalViewController",bundle: nil) modalVC.modalTransitionStyle = .CrossDissolve modalVC.modalPresentationStyle = .OverFullScreen presentViewController(modalVC,animated: true,completion: nil)
在ModalViewController中的viewDidLoad()函数中添加模糊：
let blurEffect = UIBlurEffect(style: .Light) let blurEffectView = UIVisualEffectView(effect: blurEffect) blurEffectView.frame = view.bounds blurEffectView.autoresizingMask = [.FlexibleWidth,.FlexibleHeight] view.addSubview(blurEffectView) view.sendSubviewToBack(blurEffectView)
ModalViewController有一个清晰的背景,我添加了一个带有暗模糊效果的BlurEffectView.以编程方式使用上一个代码段和Interface Builder进行尝试.
在iOS 8& 9 .CrossDissolve过渡处理“淡入淡出”,但在iOS 10(设备和模拟器)上测试后,视图显示为深色半透明背景颜色而不是模糊.
.CrossDissolve动画完成后,背景颜色将更改为实际的模糊效果背景.任何想法为什么会这样？
还试图在viewDidLoad()的开头和结尾为模态视图控制器添加layoutIfNeeded(),没有任何运气.我正在使用swift 2.3
解决方法
嗨,
您需要创建一个新的UIViewControllerAnimatedTransitioning.
然后在animateTransition中(使用transitionContext：UIViewControllerContextTransitioning),您需要编写动画代码.
现在在iOS 10中,您可以使用UIViewPropertyAnimator为UIVisualBlurEffect的BlurRadius设置动画.
这里有一个用法示例：https://github.com/PierrePerrin/PPBlurModalPresentation
第一
您需要创建模糊转换
class BlurModalPresentation: NSObject,UIViewControllerAnimatedTransitioning {
func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval{
return 0.5
}
//This is the blur view used for transition
var blurView = UIVisualEffectView(effect: UIBlurEffect(style: UIBlurEffectStyle.light))
var destinationView : UIView!
var animator: UIViewPropertyAnimator?
// This method can only be a nop if the transition is interactive and not a percentDriven interactive transition.
func animateTransition(using transitionContext: UIViewControllerContextTransitioning){
let containerView = transitionContext.containerView
_ = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.from)
let toVc = transitionContext.viewController(forKey: UITransitionContextViewControllerKey.to)
destinationView = toVc!.view
destinationView.alpha = 0.0
//Here we add the blur view and set it effect to nil
blurView.effect = nil
blurView.frame = containerView.bounds
self.blurTransition(transitionContext) {
self.unBlur(transitionContext,completion: {
self.blurView.removeFromSuperview()
transitionContext.completeTransition(true)
})
}
containerView.addSubview(toVc!.view)
containerView.addSubview(blurView)
}
//This methods add the blur to our view and our destinationView
func blurTransition(_ context : UIViewControllerContextTransitioning,completion: @escaping () -> Void){
UIViewPropertyAnimator.runningPropertyAnimator(withDuration: self.transitionDuration(using: context)/2,delay: 0,options: UIViewAnimationOptions.curveLinear,animations: {
self.destinationView.alpha = 0.5
self.blurView.effect = UIBlurEffect(style: UIBlurEffectStyle.light)
},completion: { (position) in
completion()
})
}
//This Method remove the blur view with an animation
func unBlur(_ context : UIViewControllerContextTransitioning,completion: @escaping () -> Void){
UIViewPropertyAnimator.runningPropertyAnimator(withDuration: self.transitionDuration(using: context) / 2,delay:0,animations: {
self.destinationView.alpha = 1.0
self.blurView.effect = nil
},completion: { (position) in
completion()
})
}
}
然后
您需要在ViewController中设置转换委派：
import UIKit
class ViewController: UIViewController,UIViewControllerTransitioningDelegate {
let blurModalPresentation = BlurModalPresentation()
override func viewDidLoad() {
super.viewDidLoad()
}
func showVC(){
let str = self.storyboard!
let vc = str.instantiateViewController(withIdentifier: "YourViewControllerIdentifier")
vc.transitioningDelegate = self
self.present(vc,completion: nil)
}
override func viewDidAppear(_ animated: Bool) {
super.viewDidAppear(animated)
}
func animationController(forPresented presented: UIViewController,presenting: UIViewController,source: UIViewController) -> UIViewControllerAnimatedTransitioning?{
return blurModalPresentation
}
func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning?{
return blurModalPresentation
}
}