react-native 搭建环境遇到的问题

Question

D:\reactnative\MyProject>react-native run-android
Scanning folders for symlinks in D:\reactnative\MyProject\node_modules (44ms)
JS server already running.
Building and installing the app on the device (cd android && gradlew.bat install
Debug)...
Starting a Gradle Daemon, 1 incompatible and 1 stopped Daemons could not be reus
ed, use --status for details
NDK is missing a "platforms" directory.
If you are using NDK, verify the ndk.dir is set to a valid NDK directory.  It is
 currently set to D:\安卓\bin\ndk-bundle.
If you are not using NDK, unset the NDK variable from ANDROID_NDK_HOME or local.
properties to remove this warning.

java.net.UnknownHostException: dl.google.com
Failed to connect to host: https://dl.google.com/android/repository/addons_list-
3.xml
Failed to connect to host: https://dl.google.com/android/repository/addons_list-
2.xml
Failed to connect to host: https://dl.google.com/android/repository/addons_list-
1.xml
Failed to download any source lists!
File C:\Users\Administrator\.android\repositories.cfg could not be loaded.

FAILURE: Build failed with an exception.

* What went wrong:
A problem occurred configuring project ':app'.
> Failed to find Build Tools revision 26.0.3

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug
option to get more log output.

BUILD FAILED

Total time: 35.036 secs
Could not install the app on the device, read the error above for details.
Make sure you have an Android emulator running or a device connected and have
set up your Android development environment:
https://facebook.github.io/react-native/docs/getting-started.html

D:\reactnative\MyProject>npm run android
npm ERR! missing script: android

npm ERR! A complete log of this run can be found in:
npm ERR!     C:\Users\Administrator\AppData\Roaming\npm-cache\_logs\2018-08-22T0
2_59_02_079Z-debug.log

D:\reactnative\MyProject>

==折腾我一天了 百度怎么弄也不对 请问哪里出错了

Answer 1

D:\reactnative\MyProject>npm run android
npm ERR! missing script: android

看这段提示，很明显是你执行的 npm scripts 不对。 npm run xxx 执行的 scripts 是在 package.json 文件中定义的 scripts 命令。很明显，你的项目的 package.json 里没有这个 android 这个命令。

仔细检查下 package.json 下吧。

---

还有， 你在下载 android 的一些资源时，也失败了。

java.net.UnknownHostException: dl.google.com
Failed to connect to host: https://dl.google.com/android/repository/addons_list-
3.xml
Failed to connect to host: https://dl.google.com/android/repository/addons_list-
2.xml
Failed to connect to host: https://dl.google.com/android/repository/addons_list-
1.xml
Failed to download any source lists!
File C:\Users\Administrator\.android\repositories.cfg could not be loaded.

FAILURE: Build failed with an exception.

这些资源，有的是需要翻墙的，或者是设置一些代理。请自行查找吧。