ios - 如何在 swift4 中为画廊从下到上制作 View 动画

Question

我第一次尝试制作动画。这里我的任务是收集应该从底部开始动画的图像。我正在尝试遵循此link 。在这个例子中，哇，图像从下到上有动画，这就是我想要的。我尝试过什么，如下所示。我收到类似

的错误

Cannot invoke 'visibleCells' with no arguments

如果有人帮助我做到这一点，那就太好了。预先感谢您

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

这里是如何从下到上对动画进行成像的简单过程。在这里，gif 图像动画从下到上。您将遵循该流程。

@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)
}

}