ReSwiftUndo 0.1.3-alpha.1

ReSwiftUndo 0.1.3-alpha.1

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测试已测试✓
语言语言 SwiftSwift
许可证 MIT
发布最后发布2017 年 4 月
SwiftSwift 版本3.0
SPM支持 SPM✗

由 Guillermo Peralta Scura 维护。

ReSwiftUndo 0.1.3-alpha.1

  • 作者：
  • Guillermo Peralta Scura

Swift 实现的 redux-undo，适用于与 ReSwift 一起使用

进行中

使用方法

假设您的应用状态如下所示

struct State: StateType, Equatable {
    var counter: Int = 0

    static func ==(lhr: State, rhr: State) -> Bool {
        return lhr.counter == rhr.counter
    }
}

注意：确保您的状态符合 Equatable 协议非常重要。

您的 reducer 看起来像这样

func reducer(action: Action, state: State?) -> State {
    var state = state ?? initialState()
    switch action {
    case _ as Increase:
        state.counter = state.counter + 1
    case _ as Decrease:
        state.counter = state.counter - 1
    default:
        break
    }
    return state
}

struct AppReducer: Reducer {
  func handleAction(action: Action, state: State?) -> State {
        return reducer(action, state)
    }
}

使用 ReSwiftUndo，您可以触发动作，让您回到先前的状态以及最近的状态。

包裹您的状态为 undoable 让状态看起来像这样

public struct UndoableState<T>: StateType {
    public var past: [T]
    public var present: T
    public var future: [T]
}

现在您可以通过下面的方式获取当前状态： state.present

struct AppReducer: Reducer {
    func handleAction(action: Action, state: UndoableState<State>?) -> UndoableState<State> {
        return undoable(reducer: reducer)(action, state)
    }
}

var store = Store<UndoableState<State>>(reducer: AppReducer(), state: nil)

现在您可以触发 撤销 和 重做 动作，并执行类似以下操作：

print(store.state.present.counter) // 0
store.dispatch(Increase())
print(store.state.present.counter) // 1
print(store.state.past[0].counter) // 0
store.dispatch(Undo())
print(store.state.present.counter) // 0
print(store.state.future[0].counter) // 1
store.dispatch(Redo())
print(store.state.present.counter) // 1

安装