npm install 

建議：慢的時候用下面的

npm install -g --registry=https://registry.npm.taobao.org

3.更新

react-native upgrade (然後要替換的時候輸入y，不需要替換的則輸入n)

React-native start 

npm test 

如果安裝過程發現有不對勁的地方，建議步驟：

假如npm最高是5.0版本，react-native最高是0.44版本

1、npm -v和 react-native -v 檢視版本，如果不出現版本，就說明相應的npm和react-native沒有安裝好.

2、安裝比最高版本低一個大版本最好，因為最新的版本可能各種問題,react-native目前還沒有出大版本，所以不穩定因素太多,如下：

npm uninstall  [email protected]      npm uninstall [email protected] 解除安裝高版本

npm install [email protected]

如果react-native upgrade不能跑起來，就使用npm install -g react-native-cli

出現的問題：

npm uninstall --save node-uuid
npm install --save uuid

2、[email protected] requires a peer of [email protected]~15.3.1 but none was installed.

npm install --save 
 
[email protected]~15.3.1

3、npmWARNdeprecated [email protected]: Please update to minimatch 3.0.2 or higher to avoid a RegExp DoS issue

npm install --save minimatch@3.0.2

4、Undefined symbols for architecture x86_64:

  "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::__init(char const*, unsigned long)", referenced from:

      _main in main.o

  "std::__1::basic_string<char, std::__1::char_traits<char>, std::__1::allocator<char> >::~basic_string()", referenced from:

      _main in main.o

  "std::terminate()", referenced from:

      ___clang_call_terminate in main.o

  "___cxa_begin_catch", referenced from:

      ___clang_call_terminate in main.o

  "___gxx_personality_v0", referenced from:

      _main in main.o

      Dwarf Exception Unwind Info (__eh_frame) in main.o

ld: symbol(s) not found for architecture x86_64

clang: error: linker command failed with exit code 1 (use -v to see invocation)

make: *** [main] Error 1

想了很多辦法，終於看到有人提示：編譯選項新增-lstdc++，即使用標準C++庫，問題解決！

5、

 解決辦法：找到相應的App.js只能對外匯出一個元件,也就是App.js 中元件export了兩次

             

watchman watch-del-all
rm -rf ./node_modules
npm cache clean
yarn cache clean
rm -rf $TMPDIR/react-*
yarn install
npm cache clean
yarn cache clean
yarn add uuid

沒有yarn：

watchman watch-del-all
rm -rf ./node_modules
npm cache clean
rm -rf $TMPDIR/react-*
npm install
npm cache clean
npm install uuid