react native 错误处理

react-native错误处理--

1. No bundle URL present
   Make sure you’re running a packager server or have included a .jsbundle file
   （1）ping localhost 如果ping失败
   a.改变host地址
   怎么改？ 安装 SwitchHosts，改变localHost地址
   （2）ifconfig查看电脑的ip，替换 localhost
   NSURL * url = [[RCTBundleURLProvider sharedSettings] jsBundleURLForBundleRoot:@"index" fallbackResource:nil];

NSURL * url = [NSURL URLWithString:@"http://localhost:8081/index.bundle?platform=ios&dev=true&minify=false&modulesOnly=false&runModule=true&app=org.reactjs.native.example.wwwReactNative"];

如果不行，重装cococapod（参考重装cococapod那篇文章）
删掉node_modules文件夹,重新下载 npm i
重新进入ios 文件夹，pod install ，然后返回上一个文件夹 yarn ios

2. Could not connect to development server
   https://blog.csdn.net/baidu_38027860/article/details/93878708
   执行 sudo lsof -i:8081
   ping localhost

3. GemNotFoundException
   can't find gem cocoapods (>= 0.a) with executable pod (Gem::GemNotFoundException)
   why 执行何命令导致：pod install
   solution 解决方案：
   先卸载再安装

gem install cocoapods
详细过程记录（参考重装cococapod文章）

更新/安装 gem
gem update --system

4.listen EADDRINUSE: address already in use :::8081
(1) 查找占用8081端口的pid

sudo lsof -i:8081

得到下面

COMMAND  PID      USER   FD   TYPE            DEVICE SIZE/OFF NODE NAME
node    2800 langapple   25u  IPv6 0xaa0dbc35b2da53d      0t0  TCP *:sunproxyadmin (LISTEN)

(2)kill 掉 2800

sudo kill 2800

(3)检查是否杀死

sudo lsof -i:8081

5. webview
   (1)报错：react-native-webview could not be found within the project or in these directories: node_modules
   把react-native-webview加载进来

yarn add react-native-webview

(2) 报错：requireNativeComponent: "RNCWebView" was not found in the UIManager
a.将RNCWebView 加载到ios pod中

pod install

b.删掉app
c.重启app

yarn ios