swift 自定义的的一个转场动画

先上一个效果图：

2017-03-20 20_10_49.gif

新建一个动画的类 实现UIViewControllerAnimatedTransitioning,CAAnimationDelegate

class WHLAnimatedTransition: NSObject {
    weak var transitionContext : UIViewControllerContextTransitioning!
   override init() {
        super.init()
    }
}
extension WHLAnimatedTransition : UIViewControllerAnimatedTransitioning,CAAnimationDelegate{
    
    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 0.5
    }
    func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
        self.transitionContext = transitionContext
            //获得即将消失的view
            let fromView = transitionContext.view(forKey: UITransitionContextViewKey.from)
            let toView = transitionContext.view(forKey:UITransitionContextViewKey.to)
            let containerView = transitionContext.containerView
            containerView.addSubview(fromView!)
            containerView.addSubview(toView!)
            toView?.frame = CGRect(x:0,y:64,width:containerView.frame.width,height:containerView.frame.height)
            transitionContext.completeTransition(true)
    }
    func animationDidStop(_ anim: CAAnimation, finished flag: Bool) {
        //动画完成
        self.transitionContext.completeTransition(true)
    }
}

在控制器中实现UINavigationControllerDelegate的协议

var selectImageView : UIImageView!
override func viewDidLoad() {
        super.viewDidLoad()
        self.navigationController?.delegate = self
        createCollectionView()
        selectImageView = UIImageView()
        self.view.addSubview(selectImageView)
    }
extension WHLClassifyViewController : UINavigationControllerDelegate{
    func navigationController(_ navigationController: UINavigationController, didShow viewController: UIViewController, animated: Bool) {
        if viewController != self {
            self.selectImageView.frame = CGRect.null
        }
    }
    func navigationController(_ navigationController: UINavigationController, animationControllerFor operation: UINavigationControllerOperation, from fromVC: UIViewController, to toVC: UIViewController) -> UIViewControllerAnimatedTransitioning? {
        if operation == UINavigationControllerOperation.push {
            toVC.edgesForExtendedLayout = UIRectEdge.bottom
            let animatedTransition = WHLAnimatedTransition.init()
            return animatedTransition
        }
        return nil
    }
}

实现collectionView点击的代理方法时

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {
        let cell = collectionView.cellForItem(at: indexPath)as! WHLClassifyCollectionViewCell
        let rect = cell.frame
        let cellRect = collectionView.convert(rect, to: collectionView.superview)
        self.selectImageView.frame = CGRect(x:(cell.frame.origin.x),y:cellRect.origin.y,width:(cell.frame.width),height:(cell.frame.height))
        self.selectImageView.image = cell.goodsImg.image
        let detailVC = DetailViewController()
        detailVC.goodsModel = [self.classifyModel[indexPath.item]]
        UIView.animate(withDuration: 0.6, animations: {
              self.selectImageView.frame = CGRect(x:0,y:64,width:SCREEN_WIDTH,height:300)
            
        }, completion: {(_)in
            self.navigationController?.pushViewController(detailVC, animated: true)
        })
    }

这样就欧啦！