Swift 3：在 CollectionView 中选择时放大图像

Question

美好的一天，我只在 Objective-C 或 Swift 2 中看到过这样的示例，但在运行 Xcode 8 的 Swift 3 中还没有看到。我的情况是我有一个包含一组图像的集合视图，我希望它们是当用户点击它们时放大。这是我的代码：

@IBOutlet weak var collectionView: UICollectionView!


var images = ["catPic1.jpg", "catPic2.jpg", "catPic3.jpg"]

override func viewDidLoad() {
        super.viewDidLoad()

        // Do any additional setup after loading the view.

        collectionView.delegate = self

        collectionView.dataSource = self

    } // end of view did load

 public func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int
    {
        return images.count
    }

    public func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell
    {
        let cell = collectionView.dequeueReusableCell(withReuseIdentifier: "CustomCell" , for: indexPath) as! CustomCell

        cell.myImage.image = UIImage(named: images[indexPath.row])


        return cell

    }

顺便说一句，我在另一个 swift 类中有集合视图单元格代码。代码如下：

class CustomCell: UICollectionViewCell {

    @IBOutlet weak var myImage: UIImageView!
}

所有图像都正确显示，我只需要在用户选择它们时以某种方式放大它们。谢谢。

Answer 1

您可以使用另一个UIImageView 全屏查看您的图片

func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {

    let imageView = UIImageView(image: UIImage(named: images[indexPath.row]))
    imageView.frame = self.view.frame
    imageView.backgroundColor = .black
    imageView.contentMode = .top
    imageView.isUserInteractionEnabled = true

    let tap = UITapGestureRecognizer(target: self, action: #selector(dismissFullscreenImage))
    imageView.addGestureRecognizer(tap)

    self.view.addSubview(imageView)
}

// Use to back from full mode
func dismissFullscreenImage(_ sender: UITapGestureRecognizer) {
    sender.view?.removeFromSuperview()
}