Swift项目中再给NSobject类extension中添加类属性作为闭包容器后,在外界创建给这个闭包容器赋值时,发生奔溃,异常内容如下: *** NSForwarding: warning: object 0x17027acc0 of class '_TtCE10MVVMExapleCSo8NSObject24XYPropertyBlockContainer' does not implement methodSignatureForSelector: -- trouble ahead Unreco...