子视图控制器上的PanGestureRecognizer

Question

我在子视图控制器的容器视图上设置了PanGestureRecognizer。这本质上是一个抽屉视图，所以我希望子视图控制器处理任何滚动，除了子视图控制器的表视图滚动到顶部并且用户平移时。在这种情况下，我希望容器视图手势识别器接管，以便可以将子视图控制器作为一个整体动画下来。我有一个手势识别器的代表，如果代替子视图控制器和容器视图，它只是一个表格视图，我添加了平移手势识别器。现在的方式是，委托在应该的时候返回true，但是handlePan方法没有被调用？任何想法，将不胜感激。谢谢！

所有下面的代码都在父UIViewController中，它有一个容器视图，我正在应用手势识别器。一切都正确显示，只是没有调用手势识别器方法，但委托是。

func setUpItemDetailsController() {
        guard let itemDetailsController = itemDetailsController else { return }
        add(itemDetailsController)
        itemDetailsContainerView.addSubview(itemDetailsController.view)

        let panGestureRecognizer = UIPanGestureRecognizer(target: self, action: #selector(handlePan))
        panGestureRecognizer.delegate = self
        itemDetailsContainerView.addGestureRecognizer(panGestureRecognizer)
    }

@objc func handlePan(_ sender: UIPanGestureRecognizer) {
     ...
}

extension MoverScanAndDiscoverResultController: UIGestureRecognizerDelegate {
    func gestureRecognizerShouldBegin(_ gestureRecognizer: UIGestureRecognizer) -> Bool {
        guard let panGestureRecognizer = gestureRecognizer as? UIPanGestureRecognizer else { return true }

        let translation = panGestureRecognizer.translation(in: view).y
        let topLimit = view.bounds.height - self.statusAndNavBarCombinedHeight

        print(itemDetailsTableView.contentOffset.y)

        // Allows for normal UITableView scrolling
        if translation < 0
            && resultCardViewBottomConstraint.constant == topLimit
            || itemDetailsController?.tableView.contentOffset.y ?? 0 > 0 {
            return false
        }

        return true
    }
}

Answer 1

您是否尝试过使用UIGestureRecognizerDelegate函数同时识别其他手势识别器？

class MyViewController: UIViewController {

    override func viewDidLoad() {
        super.viewDidLoad()

        // etc...

        let panGestureRecognizer = UIPanGestureRecognizer(target: self, action: #selector(panned(_:)))
        panGestureRecognizer.delegate = self
        self.tableView.addGestureRecognizer(panGestureRecognizer)
    }

    @objc
    func panned(_ sender: UIPanGestureRecognizer) {
        print("Panning")
    }
}

extension MyViewController: UIGestureRecognizerDelegate {
    func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldRecognizeSimultaneouslyWith otherGestureRecognizer: UIGestureRecognizer) -> Bool {
        return true // obviously this could be more refined if you have other gesture recognizers
    }
}

我没有尝试将手势识别器添加到容器视图中，但是将其直接添加到tableView对我来说很好。