RxSwift笔记七其他操作符

简介

    git地址: https://github.com/ReactiveX/RxSwift参考资料:http://t.swift.gg/d/2-rxswiftReactiveX是通过可观察的流实现异步编程的一种API，它结合了观察者模式、迭代器模式和函数式编程的精华，RxSwift 是 ReactiveX 编程思想的一种实现。
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订阅,是连接观察者和被观察者的操作符.

public func subscribe(on: (event: RxSwift.Event<Self.E>) -> Void) -> Disposable 就是说我们接收到的是事件，在这里一般通过 switch case 获取对应结果。

let sequenceOfInts = PublishSubject<Int>()_ = sequenceOfInts.subscribe {print($0)
}sequenceOfInts.on(.Next(1))
sequenceOfInts.on(.Completed)
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subscribeNext

指订阅next事件.

public func subscribeNext(onNext: (Self.E) -> Void) -> Disposable 因为只有一种事件，这里的 API 传入的就是事件中包含的具体的值了。

let sequenceOfInts = PublishSubject<Int>()_ = sequenceOfInts.subscribeNext {print($0)
}sequenceOfInts.on(.Next(1))
sequenceOfInts.on(.Completed)
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subscribeCompleted / subscribeError

只订阅完成/错误事件.

subscribeOnnextOnErrorOnCompleted

public func subscribe(onNext onNext: (Self.E -> Void)? = default, onError: (ErrorType -> Void)? = default, onCompleted: (() -> Void)? = default, onDisposed: (() -> Void)? = default) -> Disposable

takeUntil

当另一个序列开始发射值时，忽略原序列发射的值。

let originalSequence = PublishSubject<Int>()
let whenThisSendsNextWorldStops = PublishSubject<Int>()_ = originalSequence.takeUntil(whenThisSendsNextWorldStops).subscribe {print($0)
}originalSequence.on(.Next(1))
originalSequence.on(.Next(2))
originalSequence.on(.Next(3))whenThisSendsNextWorldStops.on(.Next(1))originalSequence.on(.Next(4))
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takeWhile

跟filter类似,filter 和 takeWhile 什么时候更能清晰表达你的意思，就用哪个。

let sequence = PublishSubject<Int>()_ = sequence.takeWhile { $0 < 4 }.subscribe {print($0)
}sequence.on(.Next(1))
sequence.on(.Next(2))
sequence.on(.Next(3))
sequence.on(.Next(4))
sequence.on(.Next(5))
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amb

处理多个序列,只会关心多个序列中最先发送数据的序列,其他序列会被忽略.

let intSequence1 = PublishSubject<Int>()
let intSequence2 = PublishSubject<Int>()
let intSequence3 = PublishSubject<Int>()let _ = [intSequence1, intSequence2, intSequence3].amb().subscribe {print($0)
}intSequence2.onNext(10) // intSequence2 最先发射
intSequence1.onNext(1)
intSequence3.onNext(100)
intSequence1.onNext(2)
intSequence3.onNext(200)
intSequence2.onNext(20)let intSequence1 = PublishSubject<Int>()
let intSequence2 = PublishSubject<Int>()let _ = intSequence1.amb(intSequence2).subscribe { // 只用于比较两个序列print($0)
}intSequence2.onNext(10) // intSequence2 最先发射
intSequence1.onNext(1)
intSequence1.onNext(2)
intSequence2.onNext(20)复制代码