ios - 扩展图像上的捏合手势识别器

Question

我已将点击手势识别器操作添加到我的 ImageView 中。点击图像后，它会扩展到全屏，然后再次点击时会关闭全屏。在图像已经展开后，如何添加捏合来缩放图像。这是我使图像全屏显示的代码。

//expand image


let newImageView: UIImageView!

@IBAction func imageTapped(_ sender: UITapGestureRecognizer)




{
    let imageView = sender.view as! UIImageView

    let scrollView = UIScrollView(frame: self.view.frame)


    let newImageView = UIImageView(image: imageView.image)
    newImageView.frame = self.view.frame
    newImageView.backgroundColor = .black
    newImageView.contentMode = .scaleAspectFit
    newImageView.isUserInteractionEnabled = true


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


    scrollView.delegate = self
    scrollView.minimumZoomScale = 1.0
    scrollView.maximumZoomScale = 5.0

    scrollView.addSubview(newImageView)

    self.view.addSubview(scrollView)
}

func viewForZooming(in scrollView: UIScrollView) -> UIView?
{
    return newImageView;
}

func dismissFullscreenImage(_ sender: UITapGestureRecognizer) {
    sender.view?.removeFromSuperview()
}

Answer 1

当您想显示完整图像时，请使用 scrollview 代替 imageView

let newImageView: UIImageView!

@IBAction func imageTapped(_ sender: UITapGestureRecognizer)
{
    let imageView = sender.view as! UIImageView

    let scrollView = UIScrollView(frame: self.view.frame);

    newImageView = UIImageView(image: imageView.image)
    newImageView.frame = self.view.frame
    newImageView.backgroundColor = .black
    newImageView.contentMode = .scaleAspectFit
    newImageView.isUserInteractionEnabled = true


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

    scrollView.delegate = self
    scrollView.minimumZoomScale = 1.0
    scrollView.maximumZoomScale = 5.0

    scrollView.addSubview(newImageView)
    self.view.addSubview(scrollView)
}

并记住viewForZooming委托(delegate)函数

 func viewForZooming(in scrollView: UIScrollView) -> UIView?
 {
     return newImageView;
 }