如何通过单击灰色部分来关闭菜单栏？

Question

这是我当前关于如何显示视图控制器然后将其分成页面一半的代码。单击灰色部分时，我试图关闭视图控制器。我不知道是否可能。现在，我用手势关闭了视图控制器。但是我必须触摸白色部分。我确定有些用户会遇到麻烦。

这是我的代码：

import UIKit

class slide: NSObject,UIViewControllerAnimatedTransitioning{

var ispresenting = false
let dimmingview = UIView()



func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
    return 0.3
}


func animateTransition(using transitionContext: UIViewControllerContextTransitioning) {
    guard let toviewcontroller = transitionContext.viewController(forKey: .to),
        let fromViewcontroller = transitionContext.viewController(forKey: .from) else { return }

     let containerview = transitionContext.containerView

    let finalWidth = toviewcontroller.view.bounds.width * 0.8
    let finalHeight = toviewcontroller.view.bounds.height


    //dims menu background
if ispresenting {
    //add dimining view
    dimmingview.backgroundColor = .black
    dimmingview.alpha = 0.0
    containerview.addSubview(dimmingview)
    dimmingview.frame = containerview.bounds
    //add menu view controller to container
    containerview.addSubview(toviewcontroller.view)

    //init frame of the screen
    toviewcontroller.view.frame = CGRect(x: -finalWidth, y: 0, width: finalWidth, height: finalHeight)
}
    //animate onto screen
    let transform = {
        self.dimmingview.alpha = 0.7
        toviewcontroller.view.transform = CGAffineTransform(translationX: finalWidth, y: 0)
    }

    let identity = {
        self.dimmingview.alpha = 0.0
       fromViewcontroller.view.transform = .identity
    }

    // Animation of the transition
    let duration = transitionDuration(using: transitionContext)
    let isCancelled = transitionContext.transitionWasCancelled
    UIView.animate(withDuration: duration, animations: {
       self.ispresenting ? transform() : identity()
    }) { (_) in
        transitionContext.completeTransition(!isCancelled)
    }
}


}