滚动视图下的iOS swift 4 imageview：双击可缩小

我已经应用了“图像视图”按收缩进行放大/缩小。这很容易。在图像视图上应用双击时，无法检测选择方法

我使用Xcode 9和swift 4。请告诉我scrollview是否应该应用双击手势

 var previewImage : UIImage? = nil


    override func viewDidLoad() {
        super.viewDidLoad()

        scrollView.minimumZoomScale = 1.0
        scrollView.maximumZoomScale = 6.0
        imageView.image = previewImage

        let doubleTap =  UITapGestureRecognizer.init(target: self, action: #selector(self.sampleTapGestureTapped(recognizer:)))
        doubleTap.numberOfTapsRequired = 2
        imageView.addGestureRecognizer(doubleTap)
        // Do any additional setu p after loading the view.
    } 

    @objc func sampleTapGestureTapped(recognizer: UITapGestureRecognizer) {
        print("Tapping working")
    }


}

extension PhotoReviewController: UIScrollViewDelegate {

    func viewForZooming(in scrollView: UIScrollView) -> UIView? {

        return imageView
    }
}

从

UIImageView

的属性

isUserInteractionEnabled

的

此类将此属性的默认值更改为false

因此，如果您只启用用户交互，您的问题应该得到解决

imageView.isUserInteractionEnabled = true

如果它仍然不起作用。检查是否有其他视图阻止此视图的触摸