常规委托和ProxyDelegate RxSwift

Question

我是RxSwift的新手，并试图在我的项目中实现此框架https://github.com/rubygarage/collection-view-layouts。

到目前为止，我已经知道了：

extension BaseLayout: HasDelegate {
    public typealias Delegate = LayoutDelegate
}

class RxLayoutDelegateDelegateProxy: DelegateProxy<BaseLayout, LayoutDelegate>, DelegateProxyType, LayoutDelegate {
    public weak private(set) var baseLayout: BaseLayout?

    public init(baseLayout: ParentObject) {
        self.baseLayout = baseLayout
        super.init(parentObject: baseLayout,
                   delegateProxy: RxLayoutDelegateDelegateProxy.self)
    }

    static func registerKnownImplementations() {
        self.register { RxLayoutDelegateDelegateProxy(baseLayout: $0) }
    }
}

extension Reactive where Base: BaseLayout {

    public var delegate: DelegateProxy<BaseLayout, LayoutDelegate> {
        return RxLayoutDelegateDelegateProxy.proxy(for: base)
    }

    var cellSize: ControlEvent<CGSize> {

    }
}

但是仍然无法弄清楚一旦获得照片后如何传递图像尺寸。有人可以帮忙吗？谢谢！

Answer 1

你很近。因为委托方法返回一个值，所以您必须像UITableView反应式扩展中的items函数那样实现它。像这样的东西：

extension BaseLayout: HasDelegate {
    public typealias Delegate = LayoutDelegate
}

class LayoutDelegateProxy
    : DelegateProxy<BaseLayout, LayoutDelegate>
    , DelegateProxyType
    , LayoutDelegate {

    init(parentObject: BaseLayout) {
        super.init(parentObject: parentObject, delegateProxy: LayoutDelegateProxy.self)
    }

    deinit {
        _cellSize.onCompleted()
    }

    public static func registerKnownImplementations() {
        self.register { LayoutDelegateProxy(parentObject: $0) }
    }

    func cellSize(indexPath: IndexPath) -> CGSize {
        return (try? _cellSize.value())?[indexPath] ?? CGSize.zero
    }

    fileprivate let _cellSize = BehaviorSubject<[IndexPath: CGSize]>(value: [:])
}

extension Reactive where Base: BaseLayout {
    var delegate: LayoutDelegateProxy {
        return LayoutDelegateProxy.proxy(for: base)
    }

    func items<Source: ObservableType>(_ source: Source) -> Disposable where Source.Element == [IndexPath: CGSize] {
        return source
            .bind(to: delegate._cellSize)
    }
}

使用示例：

let sizes = Observable<[IndexPath: CGSize]>.just([
    IndexPath(item: 0, section: 0): CGSize(width:  50, height:  50),
    IndexPath(item: 1, section: 0): CGSize(width: 100, height:  50),
    IndexPath(item: 2, section: 0): CGSize(width:  50, height: 100)
])

sizes
    .bind(to: baseLayout.rx.items)
    .disposed(by: disposeBag)