ios - 使用工厂模式时如何将委托(delegate)设置为 View Controller ？

Question

我有一个 UIViewController，在 viewDidLoad 方法中我有一个返回 View 的工厂方法。

我试图将 UIViewController 设置为这些不同 View 的委托(delegate)。但是，每个 View 都有不同的委托(delegate)，当我实际调用工厂方法时，它只返回一个 UIView。 UIView 当然不知道委托(delegate)。

我不能很好地将 delegate = ViewController 放在 ViewFactory 本身中，因为这意味着它会知道我的 ViewController，这很糟糕。我的另一个想法是，我可以将所有 View 转换为它们实际的样子，以便他们了解委托(delegate)，但这让我复制了一堆代码，所以我想知道是否有人可以在这里指出我正确的方向？

View Controller

class ViewController: UIViewController {
override func viewDidLoad() {
    super.viewDidLoad()

    //This of course would have data to populate it, but I cannot show it here.
    let data = [ViewTemplate]()

    let someView = ViewFactory.getView((data?[currentCount - 1])!)

    //so here is where I thought I could add 
    //someView.delegate
    //but of course it is just a UIView that is returned so it 
    //doesn't know anything about a delegate

    someContainerView.addSubview(someView)
}
}

struct ViewFactory {
static func getView(_ template: ViewTemplate) -> UIView {
    switch template.viewType {
        case .One:
            let bundle = Bundle.main
            let containerView = bundle.loadNibNamed("OneView", owner: self, options: nil)?.first as! OneView
            containerView.label.text = template.text
            return containerView
        case .Two:
            let bundle = Bundle.main
            let containerView = bundle.loadNibNamed("TwoView", owner: self, options: nil)?.first as! TwoView
            containerView.label.text = template.text
            return containerView
        case .Three:
            let bundle = Bundle.main
            let containerView = bundle.loadNibNamed("ThreeView", owner: self, options: nil)?.first as! ThreeView
            containerView.label.text = template.text
            return containerView
        case .Four:
            let bundle = Bundle.main
            let containerView = bundle.loadNibNamed("FourView", owner: self, options: nil)?.first as! FourView
            containerView.label.text = template.text
            return containerView
        case .Five:
            let bundle = Bundle.main
            let containerView = bundle.loadNibNamed("FiveView", owner: self, options: nil)?.first as! FiveView
            containerView.label.text = template.text
            return containerView
        case .Six:
            let bundle = Bundle.main
            let containerView = bundle.loadNibNamed("SixView", owner: self, options: nil)?.first as! SixView
            containerView.label.text = template.text
            return containerView
    }
}
}

Answer 1

您有多种选择。这是您可以使用的一种方法:

您可以使 UIView 的所有不同自定义子类都源自具有委托(delegate)属性的共同祖先。 (我们称它为 CustomView 类。)然后您可以让您的 ViewFactory 返回该类型的对象。

这是自定义 View 的基类:

class CustomView: UIView {
  public weak var delegate: AnyObject?
  //Put any other shared properties/methods of all CustomView objects here
}

作为 CustomView 子类的 View 可能如下所示:

class OneView: CustomView {
  //Extra properties/methods for a OneView object
}

class TwoView: CustomView {
  //Extra properties/methods for a TwoView object
}

最后，重构您的 ViewFactory 以返回 CustomView 类型的 View ，而不是普通的 UIView:

struct ViewFactory {
static func getView(_ template: ViewTemplate) -> CustomView {
    switch template.viewType {
        case .One:
            let bundle = Bundle.main
            let containerView = bundle.loadNibNamed("OneView", owner: self, options: nil)?.first as! OneView
            containerView.label.text = template.text
            return containerView
        //Your other cases...
    }
}