#UIKit #UIControl #gesture

ClosureSelector.swift

class ClosureSleeve {
    let closure: () -> ()
    
    init(attachTo: AnyObject, closure: @escaping () -> ()) {
        self.closure = closure
        objc_setAssociatedObject(attachTo, "[\(arc4random())]", self, .OBJC_ASSOCIATION_RETAIN)
    }
    
    @objc func invoke() {
        closure()
    }
}

enum GestureRecognizer {
    case pan, tap, pinch, swipe, longPress, screenEdge
}

extension UIView {
    
    @discardableResult
    func actionBlock(of type: GestureRecognizer, action: @escaping () -> ()) -> UIGestureRecognizer {
        let sleeve = ClosureSleeve(attachTo: self, closure: action)
        
        let gesture: UIGestureRecognizer
        
        switch type {
        case .pan:
            gesture = UIPanGestureRecognizer(target: sleeve, action: #selector(ClosureSleeve.invoke))
            
        case .tap:
            gesture = UITapGestureRecognizer(target: sleeve, action: #selector(ClosureSleeve.invoke))
            
        case .pinch:
            gesture = UIPinchGestureRecognizer(target: sleeve, action: #selector(ClosureSleeve.invoke))
            
        case .swipe:
            gesture = UISwipeGestureRecognizer(target: sleeve, action: #selector(ClosureSleeve.invoke))
            
        case .longPress:
            gesture = UILongPressGestureRecognizer(target: sleeve, action: #selector(ClosureSleeve.invoke))
            
        case .screenEdge:
            gesture = UIScreenEdgePanGestureRecognizer(target: sleeve, action: #selector(ClosureSleeve.invoke))
        }
        
        addGestureRecognizer(gesture)
        
        return gesture
    }
}

extension UIControl {
    
    func actionBlock(event: UIControlEvents, action: @escaping () -> ()) {
        let sleeve = ClosureSleeve(attachTo: self, closure: action)
        
        self.addTarget(sleeve, action: #selector(ClosureSleeve.invoke), for: event)
    }
}