渲染
父beforeCreate->父created->父beforeMount->子beforeCreate->子created->子beforeMount->子mounted->父mounted
从外到内,在从内到外
子组件更新
父beforeUpdate->子beforeUpdate->子updated->父updated
父组件更新
父beforeUpdate->父updated
父组件卸载
父beforeDestory->子beforeDestory->子destoryed->父destoryed