swift - 循环添加到 ContainerViews

Question

我想使用容器 View 来包含一个 Collection View 的三个实例。

我的网点是:

@IBOutlet weak var topContainer: UIView!
@IBOutlet weak var middleContainer: UIView!
@IBOutlet weak var bottomContainer: UIView!

我能做到:使用在 viewdidload 中重复代码的恶心解决方案:

    topContainer.translatesAutoresizingMaskIntoConstraints = false
    middleContainer.translatesAutoresizingMaskIntoConstraints = false
    bottomContainer.translatesAutoresizingMaskIntoConstraints = false
    // add child view controller view to container
    if let controller = storyboard!.instantiateViewController(withIdentifier: "collectionscroll") as? CollectionScrollViewController {
        addChild(controller)
        controller.view.translatesAutoresizingMaskIntoConstraints = false
        topContainer.addSubview(controller.view)

        NSLayoutConstraint.activate([
            controller.view.leadingAnchor.constraint(equalTo: topContainer.leadingAnchor),
            controller.view.trailingAnchor.constraint(equalTo: topContainer.trailingAnchor),
            controller.view.topAnchor.constraint(equalTo: topContainer.topAnchor),
            controller.view.bottomAnchor.constraint(equalTo: topContainer.bottomAnchor)
            ])
        controller.didMove(toParent: self)
    }

    if let controller = storyboard!.instantiateViewController(withIdentifier: "collectionscroll") as? CollectionScrollViewController {
        addChild(controller)
        controller.view.translatesAutoresizingMaskIntoConstraints = false
        middleContainer.addSubview(controller.view)


        NSLayoutConstraint.activate([
            controller.view.leadingAnchor.constraint(equalTo: middleContainer.leadingAnchor),
            controller.view.trailingAnchor.constraint(equalTo: middleContainer.trailingAnchor),
            controller.view.topAnchor.constraint(equalTo: middleContainer.topAnchor),
            controller.view.bottomAnchor.constraint(equalTo: middleContainer.bottomAnchor)
            ])
        controller.didMove(toParent: self)

    }


    if let controller = storyboard!.instantiateViewController(withIdentifier: "collectionscroll") as? CollectionScrollViewController {
        addChild(controller)
        controller.view.translatesAutoresizingMaskIntoConstraints = false
        bottomContainer.addSubview(controller.view)


        NSLayoutConstraint.activate([
            controller.view.leadingAnchor.constraint(equalTo: bottomContainer.leadingAnchor),
            controller.view.trailingAnchor.constraint(equalTo: bottomContainer.trailingAnchor),
            controller.view.topAnchor.constraint(equalTo: bottomContainer.topAnchor),
            controller.view.bottomAnchor.constraint(equalTo: bottomContainer.bottomAnchor)
            ])
        controller.didMove(toParent: self)

    }

所以为了减少重复代码，我想到了使用循环:

lazy var containers : [UIView] = [topContainer, middleContainer, bottomContainer]

    for container in containers {
        container.translatesAutoresizingMaskIntoConstraints = false
        if let controller = storyboard!.instantiateViewController(withIdentifier: "collectionscroll") as? CollectionScrollViewController {
            addChild(controller)
            controller.view.translatesAutoresizingMaskIntoConstraints = false
            topContainer.addSubview(controller.view)

            NSLayoutConstraint.activate([
                controller.view.leadingAnchor.constraint(equalTo: container.leadingAnchor),
                controller.view.trailingAnchor.constraint(equalTo: container.trailingAnchor),
                controller.view.topAnchor.constraint(equalTo: container.topAnchor),
                controller.view.bottomAnchor.constraint(equalTo: container.bottomAnchor)
                ])
            controller.didMove(toParent: self)
        }
    }

但它不起作用 - 中间 View 不填充，最后一个不滚动。

如何在不复制 pasta codez 的情况下填充我的容器？

Answer 1

我看到一个错误。当您通过添加循环来转换代码时，您忘记了将其中一个 topContainer 更改为 container。

改变:

topContainer.addSubview(controller.view)

到:

container.addSubview(controller.view)