可从多个 BehaviorRelay RxSwift 观察到

Observable from more than one BehaviorRelay RxSwift

我正在尝试使用 RxSwift 实现对 3 个不同 BehaviorRelay 的订阅。思路如下:

let disposeBag = DisposeBag()

class ClassA{

    var br1 = BehaviorRelay(value: "BR1_1")
    var br2 = BehaviorRelay(value: "BR2_1")
    var br3 = BehaviorRelay(value: "BR3_1")

    /* Some other variables */

}
let classA = ClassA()


class ClassB:CustomStringConvertible{
    let classA:ClassA

    var description: String{
        return "\(br1.value), \(br2.value), \(br3.value)"
    }

    var br1:BehaviorRelay<String>{
        return classA.br1
    }
    var br2:BehaviorRelay<String>{
        return classA.br2
    }
    var br3:BehaviorRelay<String>{
        return classA.br3
    }

    init(classA:ClassA) {
        self.classA = classA
    }

}
let classB = ClassB(classA: classA)

classB.br1.asObservable().subscribe { (value) in
    print(value)
}

classA.br1.accept("BR1_2")

它打印:

next(BR1_1)
next(BR1_2)

通过这样做,我是 "populating" 我的 ClassB 和来自 ClassA 的对象,通过设置对 ClassB 中对象的订阅,我可以对下一个事件做出反应。

但是,我想创建一个函数,例如:

func reactingFunction(br1:BehaviorRelay<String>, br2:BehaviorRelay<String>, br3:BehaviorRelay<String>){
    /**/
}

每次任何 br 产生 onNext 事件时调用。我可以为所有这些创建混合订阅吗?

谢谢

我通过实施 CombineLast 找到了解决方案:

Observable.combineLatest(classB.br1, classB.br2, classB.br3).subscribe(onNext: { (br1, br2, br3) in
    reactingFunction(br1: br1, br2: br2, br3: br3)
}).disposed(by: disposeBag)

然后我将 reactingFunction 更改为仅接受值:

func reactingFunction(br1:String, br2:String, br3:String){
    print("Reacting Function -> \(br1) & \(br2) \(br3)")
}

来自示例:

classA.br1.accept("BR1_2")
classA.br1.accept("BR1_3")
classA.br1.accept("BR1_4")
classA.br1.accept("BR1_5")
classA.br2.accept("BR2_2")
classA.br3.accept("BR3_2")
classA.br2.accept("BR2_3")

它打印:

Reacting Function -> BR1_1 & BR2_1 BR3_1
Reacting Function -> BR1_2 & BR2_1 BR3_1
Reacting Function -> BR1_3 & BR2_1 BR3_1
Reacting Function -> BR1_4 & BR2_1 BR3_1
Reacting Function -> BR1_5 & BR2_1 BR3_1
Reacting Function -> BR1_5 & BR2_2 BR3_1
Reacting Function -> BR1_5 & BR2_2 BR3_2
Reacting Function -> BR1_5 & BR2_3 BR3_2