ios - 创建不占用全屏的 UIViewController 时，如何通过点击外部来关闭它？

Question

我正在关注this tutorial在 iOS 8 中使用 frameOfPresentedViewInContainerView 制作一个覆盖 View Controller ，但我很好奇，如何根据点击可见区域之外来关闭此 View Controller ？

Answer 1

There is one popular solution where you add a UITapGestureRecognizer to the window and then perform a hit test to check if the tap was outside the modal view frame.

但是，由于您使用的是 UIPresentationController，我建议您采用更通用的解决方案:

在您的 UIPresentationController 子类中覆盖 presentationTransitionWillBegin:

override func presentationTransitionWillBegin() {
    var dimView = UIView() // Use your specific subclass here
    dimView.backgroundColor = UIColor.blackColor().colorWithAlphaComponent(0.5) // No need for this if you have your subclass defined in IB

    self.containerView?.addSubview(dimView)
    dimView.snp_makeConstraints { (make) -> Void in // I use SnapKit to avoid the NSLayoutConstraint nonsense
        make.edges.equalTo(self.containerView!)
    }
    dimView.addSubview(self.presentedViewController.view)

    let transitionCoordinator = self.presentedViewController.transitionCoordinator()

    dimView.alpha = 0
    transitionCoordinator?.animateAlongsideTransition({ (context) -> Void in
        dimView.alpha = 1
    }, completion: { (context) -> Void in

        })
    }

这将为您提供一个适当的调光 View ，该 View 将放置在您呈现的 View Controller 后面。现在完全取决于你如何处理那个变暗的 View ，你可以设置它的样式或在那里放置按钮:

我建议在界面构建器中定义这个 View ，这样会容易很多，示例可能如下所示:

class MyDimView: UIView {
    var onPrevAction: (() -> ())?
    var onNextAction: (() -> ())?
    var onTapAction: (() -> ())?

    @IBOutlet private var prevButton: UIButton!
    @IBOutlet private var nextButton: UIButton!
    @IBOutlet private var button: UIButton!

    @IBAction private func onPrevButtonTouched() {
        if let prevAction = self.onPrevAction {
            prevAction()
        }
    }

    @IBAction private func onNextButtonTouched() {
        if let nextAction = self.onNextAction {
            nextAction()
        }
    }

    @IBAction private func onViewTouched() {
        if let tapAction = self.onTapAction {
            tapAction()
        }
    }
}

这样您就可以完全控制外部发生的事情或您呈现的 View Controller 。