RN中常见警告和问题的解决方法(持续更新中..)

1.在使用FlatList的时候 missing keys for items

警告:
VirtualizedList: missing keys for items, make sure to specify a key property on each item or provide a custom keyExtractor.
方法:
_extraUniqueKey =(item ,index) => { return "index"+index+item; }
<FlatList keyExtractor = {this._extraUniqueKey}/>

2.npm start 启动服务的时候,遇到 This is probably not a problem with npm. There is likely additional logging output above

解决方法:
更新npm: 
执行:  npm update  再执行: yarn 

3.Error:Metro Bundler can't listen on port 8081

解决办法：kill 占用8081端口的其他应用
1.找到占用端口的应用
$ sudo lsof -i :8081
2.kill （40247 是应用的 PID）
kill -9 40247
3.重新启动8081即可