Warning: Encountered two children with the same key
Warning: Encountered two children with the same key, `.$/base`. Keys should be unique so that components maintain their identity across updates. Non-unique keys may cause children to be duplicated and/or omitted — the behavior is unsupported and could change in a future version.
children with the same key,
.$/base有兩個組件的key重複了
組件的key應該唯一的,方便組件在更新的時候找到對應的組件.
解決方案：
在當前頁面查找key 保證key的唯一性 Can’t call setState (or forceUpdate) on an unmounted component
Warning: Can't call setState (or forceUpdate) on an unmounted component. This is a no-op, but it indicates a memory leak in your application. To fix, cancel all subscriptions and asynchronous tasks in the componentWillUnmount method.
不能在已經被銷燬的組件中調用setState()方案
出現場景：跳轉路由 當前組件被銷燬 組件內部還存在異步操作對state的狀態信息 比如http請求,定時器setTimeOut更新state
思路就是在組件卸載之前 控制異步不進行setState
解決方案一：組件被銷燬之前重寫setState方法 不對狀態做任何改變
componentWillUnmount(){
this.setState = (state,callback)=>{
return;
};
}
解決方案二：組件被銷燬之前 可以setState 銷燬之後就不能setState
componentWillMount() {
this._isMounted = true
fetch('網絡請求').then (status, response)=>{
if (this._isMounted) {
this.setState({
activityTipsImg: response.data.tips_url,
activityTipsContent: response.data.tips_content
})
}
});
}
componentWillUnmount() {
this._isMounted = false
}