ios - 点击 super View 中嵌入的自定义 UIView 中未收到的手势识别器

Question

我正在尝试创建一个名为 MyScrollView 的自定义 UIView/Scrollview，其中包含一些标签 (UILabel)，并且这些标签接收点击手势/事件以响应用户的选择 .

为了使点击事件在 UILabel 上起作用，我确保它们都具有 userIteractionEnabled = true 并且我创建了一个委托(delegate)，如下所示:

protocol MyScrollViewDelegate {
    func labelClicked(recognizer: UITapGestureRecognizer)
}

我创建的 ScrollViewController 中使用了自定义 UIView，这个 ScrollViewController 也实现了委托(delegate)方法:

import UIKit
import Neon
class ScrollViewController: UIViewController, MyScrollViewDelegate {

var curQuestion: IPQuestion?
var type: QuestionViewType?
var lastClickedLabelTag: Int = 0 //

init(type: QuestionViewType, question: IPQuestion) {
    super.init(nibName: nil, bundle: nil)
    self.curQuestion = question
    self.type = type
}

required init?(coder aDecoder: NSCoder) {
    fatalError("init(coder:) has not been implemented")
}

override func viewDidLoad() {
    super.viewDidLoad()
    self.automaticallyAdjustsScrollViewInsets = false
}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
}

override func loadView() {
    view = MyScrollView(delegate: self, q: curQuestion!)
    view.userInteractionEnabled = true
}
}

// implementations for MyScrollViewDelegate
extension ScrollViewController {

func labelTitleArray() -> [String]? {
    print("labelTitleArray called in implemented delegate")

    return ["Comments", "Answers"]
}

func labelClicked(recognizer: UITapGestureRecognizer) {
    print("labelClicked called in implemented delegate")
    let controller = parentViewController as? ParentViewController
    controller?.labelClicked(recognizer)
    lastClickedLabelTag = recognizer.view!.tag
    }
}

// MARK: - handle parent's ViewController event
extension QuestionDetailViewController {
    func updateActiveLabelsColor(index: Int) {
        print("updating active labels color: \(index)")
        if let view = view as? MyScrollView {
            for label in (view.titleScroll.subviews[0].subviews as? [UILabel])! {
                if label.tag == index {
                    label.transform = CGAffineTransformMakeScale(1.1,1.1)
                    label.textColor = UIColor.purpleColor()
                }
                else {
                    label.transform = CGAffineTransformMakeScale(1,1)
                    label.textColor = UIColor.blackColor()
                }
            }
        }
    }
}

上面的 ScrollViewController 作为 subview Controller 添加到父 View Controller ，并定位到父 View 的顶部:

override func viewDidLoad() {
        super.viewDidLoad()
        self.automaticallyAdjustsScrollViewInsets = false
        self.view.backgroundColor = UIColor.whiteColor()
        addChildViewController(scrollViewController) // added as a child view controller here
        view.addSubview(scrollViewController.view) // here .view is MyScrollView
        scrollViewController.view.userInteractionEnabled = true
        scrollViewController.view.anchorToEdge(.Top, padding: 0, width: view.frame.size.width, height: 100)
    }

应用程序可以在 View 中加载所有内容，但点击手势/事件不会传递到自定义 MyScrollView 中的标签。为此，我做了一些谷歌搜索并阅读了 Event Delivery: Responder Chain在 Apple Developer 网站上也进行了 HitTest 。下面的hitTest函数可以在MyScrollView中触发:

override func hitTest(point: CGPoint, withEvent event: UIEvent?) -> UIView? {
        print("hit test started, point: \(point), event: \(event)")
        return self
    }

我对 hitTest 的观察是 touchesBegan() 和 touchesEnded() 方法仅在 View 中触发 当 hitTest 函数存在时。没有 hitTest，这两个函数都不会被点击调用。

但没有运气让 UILabel 响应点击手势。所以我在这里联系 SO 专家。感谢您的帮助!

Answer 1

我想我找到了 UILabel 的原因经过一番挣扎后没有回应:.addGestureRecognizer()标签的方法在 init() 中运行我的习惯方法UIView组件，这是错误的，因为 View /标签 可能尚未呈现。相反，我将该代码移至生命周期方法 layoutSubviews() , 一切开始运行良好:

var lastLabel: UILabel? = nil

        for i in 0..<scrollTitleArr.count {
            let label = UILabel()
            label.text = scrollTitleArr[i] ?? "nothing"
            print("label: \(label.text)")
            label.font = UIFont(name: "System", size: 15)
            label.textColor = (i == 0) ? MaterialColor.grey.lighten2 : MaterialColor.grey.darken2
            label.transform = (i == 0) ? CGAffineTransformMakeScale(1.1, 1.1) : CGAffineTransformMakeScale(0.9, 0.9)
            label.sizeToFit()
            label.tag = i // for tracking the label by tag number
            label.userInteractionEnabled = true
            label.addGestureRecognizer(UITapGestureRecognizer(target: self, action: #selector(self.labelClicked(_:))))

            titleContainer.addSubview(label)

            if lastLabel == nil {
                label.anchorInCorner(.TopLeft, xPad: 0, yPad: 0, width: 85, height: 40)
      //         label.anchorToEdge(.Left, padding: 2, width: 85, height: 40)
            } else {
                label.align(.ToTheRightMatchingTop, relativeTo: lastLabel!, padding: labelHorizontalGap, width: 85, height: 40)
            }

            lastLabel = label

        }

此外，我不需要实现任何 UIGestureRecognizer 委托(delegate)方法，也不需要创建容器 View 或 ScrollView userInteractionEnabled .更重要的是，当将自定义 UIView 嵌入到 super View 时，我配置了它的大小并设置了 clipsToBounds = true .

我想我应该阅读更多 UIView Apple Developer 网站上的文档。希望这会在将来帮助像我这样的人!感谢大家!