@gregheo So You Want To Be A Reactive Programming Beginner? 

@gregheo Data flows Propagation of change 

@gregheo 

@gregheo Slider 1 Slider 2 action method action method Text label Triangle 

@gregheo Subscription Observable Slider 1 Text label 60° Subscription Draw triangle 58° 59° 62° 68° … 

@gregheo Create Combine Listen Streams } 

@gregheo Observable Slider 1 Observable Slider 2 Observable merge() 

@gregheo Observable map bind map bind subscribe 

@gregheo let angleSliderObservable = angleSlider.rx.value .map({ (angle: Float) in return RightTriangle(angle: Int(angle)) }) let oppositeAngleSliderObservable = oppositeAngleSlider.rx.value .map({ (angle: Float) in return RightTriangle(oppositeAngle: Int(angle)) }) let combinedObservable = Observable.of(angleSliderObservable, oppositeAngleSliderObservable).merge() 

@gregheo let angleSliderObservable = angleSlider.rx.value .map({ (angle: Float) in return RightTriangle(angle: Int(angle)) }) let oppositeAngleSliderObservable = oppositeAngleSlider.rx.value .map({ (angle: Float) in return RightTriangle(oppositeAngle: Int(angle)) }) let combinedObservable = Observable.of(angleSliderObservable, oppositeAngleSliderObservable).merge() combinedObservable .subscribe(onNext: { (triangle: RightTriangle) in self.angleSlider.value = Float(triangle.angle) self.triangleView.triangle = triangle }) .addDisposableTo(disposeBag) combinedObservable .map({ "Angle: \($0.angle)°\nOpposite angle: \($0.oppositeAngle)°" }) .bindTo(label.rx.text) .addDisposableTo(disposeBag) 

@gregheo let angleSliderObservable = angleSlider.rx.value .map({ (angle: Float) in return RightTriangle(angle: Int(angle)) }) let oppositeAngleSliderObservable = oppositeAngleSlider.rx.value .map({ (angle: Float) in return RightTriangle(oppositeAngle: Int(angle)) }) let combinedObservable = Observable.of(angleSliderObservable, oppositeAngleSliderObservable).merge() combinedObservable .subscribe(onNext: { (triangle: RightTriangle) in self.angleSlider.value = Float(triangle.angle) self.triangleView.triangle = triangle }) .addDisposableTo(disposeBag) combinedObservable .map({ "Angle: \($0.angle)°\nOpposite angle: \($0.oppositeAngle)°" }) .bindTo(label.rx.text) .addDisposableTo(disposeBag) Reactive Extensions input output 

@gregheo Separation of Concerns 

@gregheo Declarative 

@gregheo Small Pieces of Logic 

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