网上有很多关于这个错误的帖子。我的情况是我有时可以建立连接,但大多数时候都失败了。这是失败时的错误:
PS C:\d\code\js\chatapp> react-native run-android
JS server already running.
Building and installing the app on the device (cd android && gradlew.bat installDebug)...
Starting a Gradle Daemon, 1 incompatible Daemon could not be reused, use --status for details
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:installDebug'.
> com.android.builder.testing.api.DeviceException: No connected devices!
* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.
* Get more help at https://help.gradle.org
BUILD FAILED in 15s
27 actionable tasks: 1 executed, 26 up-to-date
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
这是成功时的消息:
PS C:\d\code\js\chatapp> react-native run-android
JS server already running.
Building and installing the app on the device (cd android && gradlew.bat installDebug)...
> Task :app:installDebug
Installing APK 'app-debug.apk' on 'MHA-L29 - 8.0.0' for app:debug
Installed on 1 device.
BUILD SUCCESSFUL in 6s
27 actionable tasks: 1 executed, 26 up-to-date
'adb' is not recognized as an internal or external command,
operable program or batch file.
Starting the app (c:\AppData\Local\Android\Sdk/platform-tools/adb shell am start -n com.chatapp/com.chatapp.MainActivity...
Starting: Intent { cmp=com.chatapp/.MainActivity }
我没有很好的解释为什么有时它确实有效而其他时候却没有。在每个react-native run andrioid,USB Debugging在 Mate 9 上启用。