Swift 进击：target/action模式完美转闭包blo

Swift :

@objc public extension UIGestureRecognizer{
    private struct AssociateKeys {
        static var funcName   = "UIGestureRecognizer" + "funcName"
        static var closure    = "UIGestureRecognizer" + "closure"
    }
    
    /// 闭包回调
    func addAction(_ closure: @escaping (UIGestureRecognizer) -> Void) {
        objc_setAssociatedObject(self, &AssociateKeys.closure, closure, .OBJC_ASSOCIATION_COPY_NONATOMIC);
        addTarget(self, action: #selector(p_invoke))
    }
    
    private func p_invoke() {
        if let closure = objc_getAssociatedObject(self, &AssociateKeys.closure) as? ((UIGestureRecognizer) -> Void) {
            closure(self);
        }
    }
    
}

OC :

#import "UIGestureRecognizer+Helper.h"

- (void)addActionBlock:(void(^)(UIGestureRecognizer *reco))block {
    if (!block) {
        return;
    }

    objc_setAssociatedObject(self, _cmd, block, OBJC_ASSOCIATION_COPY_NONATOMIC);
    [self addTarget:self action:@selector(p_invoke:)];
}

- (void)p_invoke:(UIGestureRecognizer *)sender {
    void(^block)(UIGestureRecognizer *reco) = objc_getAssociatedObject(self, @selector(addActionBlock:));
    if (block) {
        block(sender);
    }
}

#import "UIBarButtonItem+Helper.h"

- (void)addActionBlock:(void (^)(UIBarButtonItem *item))block{
    if (block) {
        objc_setAssociatedObject(self, @selector(actionBlock), block, OBJC_ASSOCIATION_COPY);
        // Sets up the action.
        self.target = self;
        self.action = @selector(p_invoke);
    }
}

- (void)p_invoke {
    void(^block)(UIBarButtonItem *item) = objc_getAssociatedObject(self, @selector(addActionBlock:));
    if (block) {
        block(self);
    }
}