ios - Gif用作分页加载器时，有时不显示在 ImageView 中

Question

我正在使用带有分页的 Collection View 来显示更多数据。在 Collection View 结束时，我显示带有 gif 文件的 ImageView ，直到数据加载，然后隐藏 ImageView 。但有时 gif 无法在 ImageView 中加载。

请帮忙并提前致谢!!

我尝试过更改库 - Kingfisher、SDWebImage、ImageIO、UIImage+Gif 等，但没有帮助。还尝试在主线程上运行。

class HorizontalScrollDealCollectionView: UICollectionView {

    private var indicator:UIImageView!
    private var offset:CGFloat = 0
    private let loaderGif  =  UIImage.gif(name: "831")

    override func awakeFromNib() {
        super.awakeFromNib()

        let frame = CGRect(x: 20, y: self.frame.height/2-15, width: 30, height: 30)
        indicator = UIImageView(frame: frame)
        indicator.image = loaderGif
        indicator.backgroundColor = .blue
        self.addSubview(indicator)
        indicator.isHidden = true
    }

    override func layoutSubviews() {
        super.layoutSubviews()
        self.adjustIndicator()
    }

    func loadGifAnimatedIndicator() {
        indicator.isHidden = true
        indicator.image = loaderGif
    }

    private func adjustIndicator() {
        indicator.frame.origin.x = self.contentSize.width + (offset/2)
        let view = self.visibleCells.first
        if let scrollViewAdjuster = view as? InfiniteScrollOffsetAdjuster {
            indicator.frame.origin.y = scrollViewAdjuster.refralFrameForProgressView.height / 2 - 15
        }
        else {
            indicator.frame.origin.y = self.contentSize.height / 2 - 15;
        }
    }

    func showIndicator() {
        if indicator.isHidden == false { return }
        indicator.isHidden = false
        indicator.image = loaderGif
        indicator.startAnimating()
        UIView.animate(withDuration: 0.2) {
            self.contentInset.right = self.offset + 40
        }
    }

    func hideIndicator() {
        if indicator.isHidden { return }
        self.indicator.isHidden = true
    }

    func resetContentInset(animate:Bool = true) {
        UIView.setAnimationsEnabled(animate)
        UIView.animate(withDuration: 0.1, animations: {
            self.contentInset.right = 0
        }) { (success) in
            if !animate {
                UIView.setAnimationsEnabled(true)
            }
        }
    }
}

在 ViewController 中

//Table View Delegate
  func tableView(_ tableView: UITableView, willDisplay cell: UITableViewCell, forRowAt indexPath: IndexPath) {
        guard let homeTableViewCell = cell as? HorizontalScrollHomeTableViewCell else {
            return
        }
        homeTableViewCell.collectionView.loadGifAnimatedIndicator()
        homeTableViewCell.collectionView.reloadData()
    }

//Collection View Delegate
    func collectionView(_ collectionView: UICollectionView, willDisplay cell: UICollectionViewCell, forItemAt indexPath: IndexPath) {
        let horizontalCollView = collectionView as! HorizontalScrollDealCollectionView
        let dataIndex = horizontalCollView.tableViewCellIndex!
        let data = items[dataIndex.row]
        if (indexPath.item == data.products.count - 1) && data.moreAvailable {
            horizontalCollView.showIndicator()
            data.loadMore(completion: {
                (success) in
                horizontalCollView.hideIndicator()
                if success {horizontalCollView.reloadData()}
            })
        }
    }

屏幕截图 1

****截图2**

Answer 1

改变

private let loaderGif = UIImage.gif(name: "831")

到

private var loaderGif: UIImage { 
   return UIImage.gif(name: "831")
}

解决了问题，但表格 View 滚动变得迟缓/抖动。

还使用 DispatchQueue 异步执行此操作，但没有帮助。仍然滚动挂起。

func loadGifAnimatedIndicator() {
  indicator.isHidden = true
  DispatchQueue.main.async {
    self.indicator.image = self.loaderGif
  }
}