vue中prop父子嵌套多层传值报错解决

使用prop嵌套多层传值时报错

[Vue warn]: Avoid mutating a prop directly since the value will be overwritten whenever the parent component re-renders. Instead, use a data or computed property based on the prop's value.

解决办法：使用中间变量myshow，在watch中间监听变化通知爷爷组件