今天講GitHub - RxSwiftCommunity/RxGesture，RxGesture是封裝UIGestureRecognizer的方法，幫助我們在任何view上面進行各種手勢的偵測。

Before & After

在遇到RxGesture之前，我是這樣寫

let myView: UIView = UIView()

let tapGesture = UITapGestureRecognizer()
myView.addGestureRecognizer(tapGesture)

tapGesture.rx.event
    .debug("Tap")
    .subscribe()
    .disposed(by: disposeBag)

建立一個UITapGestureRecognizer()，給myView加入手勢的識別，在用Rx的方式監聽手勢的事件。

當我遇到RxGesture之後，我變成這樣寫

let myView: UIView = UIView()

myView.rx.tapGesture()
    .when(.recognized)
    .debug("Tap")
    .subscribe()
    .disposed(by: disposeBag)

myView擴充了tap手勢的事件，when可以幫助我們過濾UIGestureRecognizerState，使用時監聽即可。

常用的手勢

以下就記錄一下常用的手勢，假設我有一個UIView叫做myView

let myView = UIView(frame: .zero)
 
self.view.addSubview(myView)

myView.snp.makeConstraints { make in
    make.width.height.equalTo(200)
    make.center.equalToSuperview()
}

Tap 點一下

myView.rx.tapGesture()
    .when(.recognized)
    .subscribe(onNext: { _ in
        print("Tap")
    })
    .disposed(by: disposeBag)

Double Click 點兩下

myView.rx.tapGesture() { gesture, _ in
        gesture.numberOfTapsRequired = 2
    }
    .when(.recognized)
    .subscribe(onNext: { _ in
        print("Double Click")
    })
    .disposed(by: disposeBag)

Long Press 長按

myView.rx.longPressGesture()
    .when(.began)
    .subscribe(onNext: { _ in
        print("Long Press")
    })
    .disposed(by: disposeBag)

Pan 拖移

myView.rx.panGesture()
    .when(.began, .changed, .ended)
    .subscribe(onNext: {
        $0.view?.center = $0.location(in: self.view)
        print("panGesture: \($0.state)")
    })
    .disposed(by: disposeBag)

Swipe 滑動

myView.rx.swipeGesture(.up, .down)
    .when(.recognized)
    .subscribe(onNext: {
        print("Swipe \($0.direction.rawValue)")
    })
    .disposed(by: disposeBag)

Pinch 縮放

myView.rx.pinchGesture()
    .when(.began, .changed, .ended)
    .subscribe(onNext: {
        $0.view?.transform = CGAffineTransform(scaleX: $0.scale, y: $0.scale)

        print("Pinch \($0.scale)")
    })
    .disposed(by: disposeBag)

Rotation 旋轉

myView.rx.rotationGesture()
    .when(.began, .changed, .ended)
    .subscribe(onNext: {
        let angle = $0.rotation * (180 / CGFloat(Double.pi))
        $0.view?.transform = CGAffineTransform(rotationAngle: $0.rotation)

        print("Rotation: \($0.state), \(angle)")
    })
    .disposed(by: disposeBag)

以上，就是今天介紹RxGesture的內容，原本對手勢沒到很了解，工作上也不太接觸，反倒是趁這機會接觸了一下，滿有趣的

倒數兩天，相處時間不多了，明天見囉，大家掰掰