上下文：
在我的主ViewController中，我有一个scrollView，里面有一些对象（它们是UIViews）。当点击/选择其中一个UIView时，我会在UIView中对UITextView进行动画处理，以与所选对象一起使用。 （一次只能显示一个UIView）
出现在对象选择上的UIView被分离为名为AdjunctiveTextView的单独类。
问题/目标：
（下面提供的示例代码将清楚地说明这一点，我也评论了代码中的问题所在）
当一个对象被点击并且有一个带有文本的相邻UIView时，我想让那个相邻的UIView跟在scrollView之后。
问题：
为什么UIPanGestureRecognizer无法正常工作？要正确翻译backView需要什么？
我的尝试：（如下所示）
我的尝试只是通过panGesture使backView本身“可拖动”。当我滚动scrollView时，什么也没发生。
（我只包含了代码的相关部分）
class ViewController: UIViewController {
let adjunctiveTextView = AdjunctiveTextView()
// this is a delegate method which gets called when an object is tapped in the scrollView
func scrollViewObjectIsTapped(_ objectScrollView: ObjectScrollView, object: AvailableObject) {
** adjunctiveTextView.scrollView = scrollView // **Edited! (scrollView is the name of the scrollView in this class too)
adjunctiveTextView.showView(passInObject: AvailableObject)
}
}
class AdjunctiveTextView: NSObject {
lazy var backView: UIView = {
//backView setup
}
lazy var textView: UITextView = {
//textView setup
}
//additional init and setup
** weak var scrollView : UIScrollView! // **Edited!
func showView(passInObject: AvailableObject) {
if let window = UIApplication.shared.keyWindow {
// the issue must either be here in the PanGesture setup
let panG = UIPanGestureRecognizer(target: self, action: #selector(translateView(sender:)))
panG.cancelsTouchesInView = false
// window.addGestureRecognizer(panG)
** scrollView.addGestureRecognizer(panG) // **Edited!
window.addSubview(backView)
textView.text = passInObject.information
backView.frame = CGRect(x: passInObject.frame.minX, y: passInObject.minY, width: window.frame.width - passInObject.maxX - 6, height: textView.bounds.height + 5)
backView.alpha = 0
//it animates a change of the backViews x position and alpha.
UIView.animate(withDuration: 0.42, delay: 0, options: .curveEaseInOut, animations: {
self.backView.alpha = 1
self.backView.frame = CGRect(x: passInObject.frame.minX + passInObject.frame.width, y: passInObject.minY, width: window.frame.width - passInObject.maxX - 6, height: textView.bounds.height + 5)
}, completion: nil)
}
}
// or the issue is here in the handle function for the PanGesture.
@objc private func translateView(sender: UIPanGestureRecognizer) {
if let window = UIApplication.shared.keyWindow {
let translation = sender.translation(in: window) //Have tried setting this to scrollView also
switch sender.state {
case .began, .changed:
backView.center = CGPoint(x: backView.center.x, y: backView.center.y + translation.y)
sender.setTranslation(CGPoint.zero, in: window) //Have tried setting this to sccrollView also
break
case .ended:
break
default:
break
}
}
}
}
感谢您阅读我的问题。
答案 0 :(得分：0)
我只是向您的scrollView添加一个弱引用，然后将平移手势添加到scrollView。它可以根据需要工作。如果您想恢复原来的行为，可以考虑向后视图添加另一个平移手势。
class AdjunctiveTextView: NSObject {
lazy var backView: UIView = {
//backView setup
return UIView.init()
}()
lazy var textView: UITextView = {
//textView setup
return UITextView.init(frame: CGRect.init(x: 0, y: 0, width: 300, height: 100))
}()
weak var scrollView: UIScrollView!
//additional init and setup
func showView(passInObject: AvailableObject) {
if let window = UIApplication.shared.keyWindow {
// the issue must either be here in the PanGesture setup
let panG = UIPanGestureRecognizer(target: self, action: #selector(translateView(sender:)))
panG.cancelsTouchesInView = false
// passInObject.addGestureRecognizer(panG)
scrollView.addGestureRecognizer(panG)
window.addSubview(backView)
textView.text = passInObject.information
textView.backgroundColor = UIColor.blue
backView.addSubview(textView)
backView.frame = CGRect(x: passInObject.frame.minX, y: passInObject.frame.minY, width: window.frame.width - passInObject.frame.maxX - 6, height: textView.bounds.height + 5)
backView.alpha = 0
//it animates a change of the backViews x position and alpha.
UIView.animate(withDuration: 0.42, delay: 0, options: .curveEaseInOut, animations: {
self.backView.alpha = 1
self.backView.frame = CGRect(x: passInObject.frame.minX + passInObject.frame.width , y: passInObject.frame.minY , width: window.frame.width - passInObject.frame.maxX - 6, height: self.textView.bounds.height + 5)
self.backView.backgroundColor = UIColor.red
}, completion: nil)
}
}
// or the issue is here in the handle function for the PanGesture.
@objc private func translateView(sender: UIPanGestureRecognizer) {
if let window = UIApplication.shared.keyWindow {
let translation = sender.translation(in: window)
switch sender.state {
case .began, .changed:
backView.center = CGPoint(x: backView.center.x, y: backView.center.y + translation.y)
sender.setTranslation(CGPoint.zero, in: window)
break
case .ended:
break
default:
break
}
}
}
}
class ObjectScrollView: UIScrollView{
}
class AvailableObject: UIView{
var information: String!
}
class MySCNViewController: UIViewController {
@IBOutlet weak var oScrollView: ObjectScrollView!
// this is a delegate method which gets called when an object is tapped in the scrollView
func scrollViewObjectIsTapped(_ objectScrollView: ObjectScrollView, object: AvailableObject) {
adjunctiveTextView.showView(passInObject: object)
}
let adjunctiveTextView = AdjunctiveTextView()
let ao = AvailableObject.init(frame: CGRect.init(x: 0, y: 0, width: 200, height: 200))
override func viewDidLoad() {
super.viewDidLoad()
ao.information = "test"
adjunctiveTextView.scrollView = oScrollView
ao.backgroundColor = UIColor.yellow
}
@IBAction func tap(_ sender: Any?){
scrollViewObjectIsTapped(oScrollView, object: ao)}
}