Question

在回答this之后，我设法将ViewControllerB的半峰形式添加到ViewControllerA中。但是，在示例中，ViewControllerA只是一个红色视图。我想将其连接到IB以便对其进行自定义。我尝试在类ViewControllerB的IB中创建一个视图控制器，并将其视图之一连接到@IBOutlet var menuView: UIView!，而不是通过编程方式创建menuView（如示例中所示）。但是，将nil作为子视图添加到视图时发现menuView。任何帮助都会很棒。谢谢！

Answer 1

一些观察结果：

在该示例中，有一行显示：
```
let vc = ViewControllerB()
```
您可以在NIB中定义该视图控制器的视图，这样可以很好地工作。但是，如果您使用情节提要，请将其替换为...
```
let vc = storyboard!.instantiateViewController(withIdentifier: “identifier")
```
...其中identifier是您在IB的“身份检查器”中为该场景提供的一些字符串，作为“故事板ID”。

如果这是由按钮或类似的东西触发的，则您也可以在该示例中删除此gotoVCB，然后像往常一样在IB中进行模态表示（例如 control -从按钮拖动到下一个场景），然后选择“模态呈现”。但是您必须确保配置了所有init方法，例如：

class ViewControllerB: UIViewController {

    // used if you use NIBs or just call `init()`

    override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
        super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
        configure()
    }

    // used if you use storyboards

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        configure()
    }

    private func configure() {
        modalPresentationStyle = .custom
        transitioningDelegate = self
    }

    ...
}

与紧迫的问题无关，我建议将that answer’s代码拆分为单独的对象，以防止视图控制器“膨胀”，并更好地将过渡的委托对象，动画控制器等之间的职责分开

例如，也许：

class ViewControllerB: UIViewController {

    let customTransitioningDelegate = PopUpMenuTransitioningDelegate()

    override init(nibName nibNameOrNil: String?, bundle nibBundleOrNil: Bundle?) {
        super.init(nibName: nibNameOrNil, bundle: nibBundleOrNil)
        configure()
    }

    required init?(coder aDecoder: NSCoder) {
        super.init(coder: aDecoder)
        configure()
    }

    func configure() {
        modalPresentationStyle = .custom
        transitioningDelegate = customTransitioningDelegate
    }

}

和

class PopUpMenuTransitioningDelegate: NSObject, UIViewControllerTransitioningDelegate {
    func animationController(forPresented presented: UIViewController, presenting: UIViewController, source: UIViewController) -> UIViewControllerAnimatedTransitioning? {
        return PopUpMenuAnimationController(transitionType: .presenting)
    }

    func animationController(forDismissed dismissed: UIViewController) -> UIViewControllerAnimatedTransitioning? {
        return PopUpMenuAnimationController(transitionType: .dismissing)
    }
}

和

class PopUpMenuAnimationController: NSObject, UIViewControllerAnimatedTransitioning {
    enum TransitionType {
        case presenting
        case dismissing
    }

    let transitionType: TransitionType

    init(transitionType: TransitionType) {
        self.transitionType = transitionType
        super.init()
    }

    func transitionDuration(using transitionContext: UIViewControllerContextTransitioning?) -> TimeInterval {
        return 1
    }

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

        switch transitionType {
        case .presenting:
            containerView.addSubview(toVC.view)

            var rect = fromVC.view.bounds
            let menuHeight = fromVC.view.bounds.height / 2
            rect.origin.y += fromVC.view.bounds.height
            rect.size.height = menuHeight
            toVC.view.frame = rect
            toVC.view.alpha = 0

            UIView.animate(withDuration: 0.4, delay: 0, options: [.curveEaseOut], animations: {
                rect.origin.y = menuHeight
                toVC.view.frame = rect
                toVC.view.alpha = 1
            }, completion: { _ in
                transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
            })

        case .dismissing:
            UIView.animate(withDuration: 0.4, delay: 0, options: [.curveEaseOut], animations: {
                var rect = fromVC.view.frame
                rect.origin.y = toVC.view.bounds.height
                fromVC.view.frame = rect
                fromVC.view.alpha = 0
            }, completion: { _ in
                transitionContext.completeTransition(!transitionContext.transitionWasCancelled)
            })
        }
    }
}

这将过渡的委托和动画控制器与视图控制器分离，并允许您在需要时将其与其他视图控制器一起使用。

注意，我对completeTransition的参数也要多加注意。一旦开始使用交互式过渡，您可能会支持可取消的过渡。

将以编程方式创建的视图连接到IB

1 个答案: