iOS指定需要的控件上才显示自定义UIMenuItem

#pragma mark - 防止textView也显示自定义的item

- (BOOL)canPerformAction:(SEL)action withSender:(id)sender

{

    if (self.addTextTf.isFirstResponder) {

        //屏蔽自定义的菜单

        if (action == @selector(copyClick:) || action == @selector(deleteClick:) || action == @selector(bigClick:))

        {

            return NO;

        }

    }

    return [super canPerformAction:action withSender:sender];

}