【Swift】UIColorPickerViewControllerをRxSwiftに対応した

はじめに

1ヶ月前くらいからRxSwiftを学習し始めまして、最近はRxSwiftを使って個人開発をしています。
UIColorPickerViewControllerがRxSwiftに対応していなかったのでDelegateをRxSwiftで使えるようにしてみました。

何をするか

colorPickerViewControllerDidSelectColorとcolorPickerViewControllerDidFinishをRxSwiftで使えるようにする

extension ViewController: UIColorPickerViewControllerDelegate {
    func colorPickerViewControllerDidSelectColor(_ viewController: UIColorPickerViewController) {
    }

    func colorPickerViewController(_ viewController: UIColorPickerViewController, didSelect color: UIColor, continuously: Bool) {
    }
}

実装

import RxCocoa
import RxSwift
import UIKit

public extension Reactive where Base: UIColorPickerViewController {
    var didFinish: Observable<Void> {
        return RxUIColorPickerViewProxy.proxy(for: base)
            .didFinishSubject
            .asObservable()
    }

    var didSelectColor: Observable<(UIColor, Bool)> {
        return RxUIColorPickerViewProxy.proxy(for: base)
            .didSelectColorSubject
            .asObservable()
    }
}

public typealias UIColorPickerDelegate = UIColorPickerViewControllerDelegate

extension UIColorPickerViewController: HasDelegate {
    public typealias delegate = UIColorPickerDelegate
}

class RxUIColorPickerViewProxy: DelegateProxy<UIColorPickerViewController, UIColorPickerDelegate>, DelegateProxyType, UIColorPickerViewControllerDelegate {
    public init(colorPicker: UIColorPickerViewController) {
        super.init(parentObject: colorPicker, delegateProxy: RxUIColorPickerViewProxy.self)
    }

    // MARK: DelegateProxyType

    static func registerKnownImplementations() {
        register { RxUIColorPickerViewProxy(colorPicker: $0) }
    }

    static func currentDelegate(for object: UIColorPickerViewController) -> UIColorPickerViewControllerDelegate? {
        return object.delegate
    }

    static func setCurrentDelegate(_ delegate: UIColorPickerViewControllerDelegate?, to object: UIColorPickerViewController) {
        object.delegate = delegate
    }

    // MARK: Proxy Subject

    internal lazy var didFinishSubject = PublishSubject<Void>()
    internal lazy var didSelectColorSubject = PublishSubject<(UIColor, Bool)>()

    // MARK: UIColorPickerViewControllerDelegate

    func colorPickerViewControllerDidFinish(_: UIColorPickerViewController) {
        didFinishSubject.onNext(())
    }

    func colorPickerViewController(_: UIColorPickerViewController, didSelect color: UIColor, continuously: Bool) {
        didSelectColorSubject.onNext((color, continuously))
    }

    // MARK: Completed

    deinit {
        self.didFinishSubject.onCompleted()
        self.didSelectColorSubject.onCompleted()
    }
}

使い方

colorPicker.rx.didFinish
    .subscribe(onNext: { _ in
        print("終了しました")
    })
    .disposed(by: disposeBag)

colorPicker.rx.didSelectColor
    .subscribe(onNext: { [weak self] color, continuously in
        print("色を選択しました")
    })
    .disposed(by: disposeBag)

おわり

RxSwiftはめっちゃ便利！！
でも、これからはCombineかな？