如何在swift4中为图库从底部到顶部设置动画

Question

我第一次尝试做动画。在这里，我的任务是图像的集合应该从底部动画。我想跟随这个link。在这个例子中，哇图像是从下到上的动画，这就是我想要的。我曾尝试过，下面给出了。我得到的错误就像

不能在没有参数的情况下调用'visibleCells'

如果有人帮我做这件事，那就太好了。先感谢您

import UIKit

class GalleryViewController: UIViewController {

    @IBOutlet weak var collectionview_gallery: UICollectionView!
    var imgarr = [UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png"),UIImage(named: "1.png"),UIImage(named: "11.png"),UIImage(named: "111.png"),UIImage(named: "1111.png")]
    override func viewDidLoad() {
        super.viewDidLoad()
        collectionview_gallery.delegate = self
        collectionview_gallery.dataSource = self
        collectionview_gallery.register(UINib(nibName: "GalleryCollectionViewCell", bundle: nil), forCellWithReuseIdentifier: "GalleryCollectionViewCell")
    }
    override func viewWillAppear(_ animated: Bool) {
        animateTable()
    }

    func animateTable() {
        collectionview_gallery.reloadData()

        let cells = collectionview_gallery.visibleCells()
        let tableHeight: CGFloat = collectionview_gallery.bounds.size.height

        for i in cells {
            let cell: UICollectionViewCell = i as UICollectionViewCell
            cell.transform = CGAffineTransformMakeTranslation(0, tableHeight)
        }

        var index = 0

        for a in cells {
            let cell: UICollectionViewCell = a as UICollectionViewCell
            UIView.animateWithDuration(1.5, delay: 0.05 * Double(index), usingSpringWithDamping: 0.8, initialSpringVelocity: 0, options: nil, animations: {
                cell.transform = CGAffineTransformMakeTranslation(0, 0);
            }, completion: nil)

            index += 1
        }
    }


}
extension GalleryViewController: UICollectionViewDelegate,UICollectionViewDataSource{
    func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
        return 50

    }

    func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
        let cell = collectionview_gallery.dequeueReusableCell(withReuseIdentifier: "GalleryCollectionViewCell", for: indexPath) as! GalleryCollectionViewCell
        cell.image_gallery.image = imgarr[indexPath.row]
        return cell
    }


}

Answer 1

这里简单的过程如何将动画从底部到顶部。在这里，gif图像动画自下而上。你会按照这个过程。

@IBOutlet weak var eblLogo: UIImageView!
@IBOutlet var nrbcGif: UIImageView?

var heightScrren : CGFloat = 0.0

override func viewDidLoad() {
    super.viewDidLoad()

    let logoHeight = eblLogo.frame.origin.y + eblLogo.frame.height + 10
    heightScrren = logoHeight
    nrbcGif?.loadGif(name: "spin")

}

override func viewDidAppear(_ animated: Bool) {
    UIView.animate(withDuration: 2, delay: 1, options: [.curveEaseOut],
                   animations: {

                    self.nrbcGif?.center.y -= self.view.bounds.height - 500
                    self.view.layoutIfNeeded()

    }, completion: nil)
}

}