当我通常通过终端从 Android 虚拟设备（模拟器）中的可视代码运行我的 react-native 时npx react-native run android，突然我遇到了这个错误
1. info Running jetifier to migrate libraries to AndroidX. You can
disable it using "--no-jetifier" flag. Jetifier found 954 file(s) to
forward-jetify. Using 8 workers... info Starting JS server... info
Launching emulator... error Failed to launch emulator. Reason: Could
not start emulator within 30 seconds.. warn Please launch an
emulator manually or connect a device. Otherwise app may fail to
launch. info Installing the app...
> Configure project :react-native-firebase_app :react-native-firebase_app package.json found at
C:\Users\admin\Desktop\TheOriginalsAgency\Stage-pre-emcauche\MilinusApp\node_modules\@react-native-firebase\app\package.json
:react-native-firebase_app:firebase.bom using default value: 28.1.0
:react-native-firebase_app:play.play-services-auth using default
value: 19.0.0 :react-native-firebase_app package.json found at
C:\Users\admin\Desktop\TheOriginalsAgency\Stage-pre-emcauche\MilinusApp\node_modules\@react-native-firebase\app\package.json
:react-native-firebase_app:version set from package.json: 12.1.0
(12,1,0 - 12001000) :react-native-firebase_app:android.compileSdk
using custom value: 29 :react-native-firebase_app:android.targetSdk
using custom value: 29 :react-native-firebase_app:android.minSdk
using custom value: 21
:react-native-firebase_app:reactNativeAndroidDir
C:\Users\admin\Desktop\TheOriginalsAgency\Stage-pre-emcauche\MilinusApp\node_modules\react-native\android
> Task :app:installDebug FAILED Skipping device 'emulator-5554' (emulator-5554): Device is OFFLINE. 64 actionable tasks: 2 executed,
62 up-to-date
FAILURE: Build failed with an exception.
* What went wrong: Execution failed for task ':app:installDebug'.
> com.android.builder.testing.api.DeviceException: No online devices found.
* 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 16s
error Failed to install the app. Make sure you have the Android
development environment set up:
https://reactnative.dev/docs/environment-setup. Error: Command
failed: gradlew.bat app:installDebug -PreactNativeDevServerPort=8081
FAILURE: Build failed with an exception.
* What went wrong: Execution failed for task ':app:installDebug'.
> com.android.builder.testing.api.DeviceException: No online devices found.
* 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 16s
at makeError (C:\Users\admin\Desktop\TheOriginalsAgency\Stage-pre-emcauche\MilinusApp\node_modules\execa\index.js:174:9)
at C:\Users\admin\Desktop\TheOriginalsAgency\Stage-pre-emcauche\MilinusApp\node_modules\execa\index.js:278:16
at processTicksAndRejections (internal/process/task_queues.js:94:5)
at async runOnAllDevices (C:\Users\admin\Desktop\TheOriginalsAgency\Stage-pre-emcauche\MilinusApp\node_modules\@react-native-community\cli-platform-android\build\commands\runAndroid\runOnAllDevices.js:94:5)
at async Command.handleAction (C:\Users\admin\Desktop\TheOriginalsAgency\Stage-pre-emcauche\MilinusApp\node_modules\react-native\node_modules\@react-native-community\cli\build\index.js:186:9)
info Run CLI with --verbose flag for more details.