如何在swift4中为画廊从下到上设置动画

Question

我第一次尝试做动画。在这里，我的任务是收集应该从底部开始动画的图像。我正在尝试关注这个link。在这个例子中，哇，图像是从下到上动画的，这就是我想要的。我试过什么，它在下面给出。我得到一个像

这样的错误

不能在没有参数的情况下调用“visibleCells”

如果有人帮助我这样做，那就太好了。提前谢谢你

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图像动画自下而上。在这里，从下到上的 gif 图像动画。你会遵循这个过程。

@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)
}

}