在滚动视图中拖动 uiview

Posted 2023-03-14

【中文标题】在滚动视图中拖动 uiview

【英文标题】：Dragging a uiview in a scrollview

【发布时间】：2019-04-15 08:24:44

【问题描述】：

我有一个包含图像视图的滚动视图。我向该图像添加了一些 UIview，我想将它们拖放到图像区域中。

我已经在使用 UIPanGestureRecognizer (Draggable UIView Swift 3) 但它不起作用。

@IBOutlet weak var mapImage: UIImageView!
@IBOutlet weak var scrollView: UIScrollView!
 override func viewDidLoad() 
        let viewDemo = UIView()
        scrollView.minimumZoomScale = 1.0
        scrollView.maximumZoomScale = 6.0
        let panGesture = UIPanGestureRecognizer(target: self, action: 
        #selector(moveObject(_:)))
        viewDemo.frame = CGRect(x: 50, y: 50, width: 40, height: 40)
        viewDemo.backgroundColor = .red
        viewDemo.layer.cornerRadius = 20
        viewDemo.isUserInteractionEnabled = true
        viewDemo.addGestureRecognizer(panGesture)
        mapImage.addSubview(viewDemo)


   @objc func moveObject(_ gesture: UIPanGestureRecognizer)

        //1. Check That We Have A Valid Draggable View
        guard let draggedObject = gesture.view else  return 

        if gesture.state == .began || gesture.state == .changed 

            //2. Set The Translation & Move The View
            let translation = gesture.translation(in: self.view)
            draggedObject.center = CGPoint(x: draggedObject.center.x + translation.x, y: draggedObject.center.y + translation.y)
            gesture.setTranslation(CGPoint.zero, in: self.view)


        else if gesture.state == .ended 

        
    

当我拖放 UIview 时，moveObject 没有执行。 我已经尝试使用 scrollView?.isScrollEnabled = false 禁用滚动滚动视图

【参考方案1】：

您必须启用UIImageView 的用户交互。

mapImage.isUserInteractionEnabled = true