AVPlayerStatusChangeHandler.swift

// Using https://gist.github.com/swillits/93206997e7d1bff4d08e24e23173820e


extension AVPlayer {
    private struct AssociatedKeys {
        static var statusChangeHandler = "ag_statusChangeHandler"
        static var statusReceptionist = "ag_statusReceptionist"
    }
    
    var statusChangeHandler: ((AVPlayerStatus) -> ())? {
        get {
            return objc_getAssociatedObject(self, &AssociatedKeys.statusChangeHandler) as? ((AVPlayerStatus) -> ())  
        }
        set {
            if let closure: Any = newValue {
                objc_setAssociatedObject(self, &AssociatedKeys.statusChangeHandler, closure, .OBJC_ASSOCIATION_COPY)
                
                statusReceptionist = Receptionist(forKeyPath: "status", of: self, handler: { [weak self] info in
                    if let player = self {
                        player.statusChangeHandler?(player.status)
                    }
                })
                
            } else {
                objc_setAssociatedObject(self, &AssociatedKeys.statusChangeHandler, nil, .OBJC_ASSOCIATION_COPY)
                statusReceptionist = nil
            }
        }
    }
    
    
    private var statusReceptionist: Receptionist? {
        get {
            return objc_getAssociatedObject(self, &AssociatedKeys.statusReceptionist) as? Receptionist
        }
        set {
            objc_setAssociatedObject(self, &AssociatedKeys.statusReceptionist, newValue, .OBJC_ASSOCIATION_RETAIN)
        }
    }
}