Develop Reference

Error connecting to emulator in react-native project

info JS server already running.
/bin/sh: 1: adb: not found
info Launching emulator...
error Failed to launch emulator. Reason: The emulator (Pixel_4_XL) quit before it finished opening. You can try starting the emulator manually from the terminal with: emulator #Pixel_4_XL.
warn Please launch an emulator manually or connect a device. Otherwise app may fail to launch.
info Installing the app...
5 actionable tasks: 5 up-to-date
FAILURE: Build failed with an exception.
What went wrong:
Could not determine the dependencies of task ':app:compileDebugJavaWithJavac'.
SDK location not found. Define a valid SDK location with an ANDROID_HOME environment variable or by setting the sdk.dir path in your project's local properties file at '/home/oem/AwesomeProject/android/local.properties'.
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
BUİLD FAILED in 7s
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 app:installDebug -PreactNativeDevServerPort=8081
FAILURE: Build failed with an exception.
What went wrong:
Could not determine the dependencies of task ':app:compileDebugJavaWithJavac'.
SDK location not found. Define a valid SDK location with an ANDROID_HOME environment variable or by setting the sdk.dir path in your project's local properties file at '/home/oem/AwesomeProject/android/local.properties'.
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
BUİLD FAILED in 7s
at makeError (/home/oem/AwesomeProject/node_modules/execa/index.js:174:9)
at /home/oem/AwesomeProject/node_modules/execa/index.js:278:16
at processTicksAndRejections (internal/process/task_queues.js:95:5)
at async runOnAllDevices (/home/oem/AwesomeProject/node_modules/#react-native-community/cli-platform-android/build/commands/runAndroid/runOnAllDevices.js:85:5)
at async Command.handleAction (/home/oem/AwesomeProject/node_modules/react-native/node_modules/#react-native-community/cli/build/index.js:108:9)
info Run CLI with --verbose flag for more details.
I'm using linuxmint. npx can't connect to emulator in react-native run-android code, what's the problem?

React Native Issue while setting up new Project macOs

$ react-native run-android
info Running jetifier to migrate libraries to AndroidX. You can disable it using "--no-jetifier" flag.
Jetifier found 967 file(s) to forward-jetify. Using 4 workers...
info JS server already running.
info Installing the app...
FAILURE: Build failed with an exception.
What went wrong:
Could not initialize class org.codehaus.groovy.runtime.InvokerHelper
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 669ms
error Failed to install the app. Make sure you have the Android development environment set up: https://reactnative.dev/docs/environment-setup. Run CLI with --verbose flag for more details.
Error: Command failed: ./gradlew app:installDebug -PreactNativeDevServerPort=8081
But it was running perfectly on ios simulator only problem while running or android emulator

In gradle-wrapper.properties
distributionUrl=https://services.gradle.org/distributions/gradle-6.3-all.zip

Failed to install the app in react-native

Android
My application was running perfectly before and after some changes in some js files this error appeared
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:installDebug'.
> com.android.builder.testing.api.DeviceException: com.android.ddmlib.InstallException: INSTALL_FAILED_INSUFFICIENT_STORAGE
* 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 1m 0s
error Failed to install the app. Make sure you have the Android development environment set up: https://reactnative.dev/docs/environment-setup. Run CLI with --verbose flag for more details.
Error: Command failed: gradlew.bat app:installDebug -PreactNativeDevServerPort=8081
Unable to install C:\projects\Maheema\android\app\build\outputs\apk\debug\app-debug.apk

Try
Gradlew clean
In android directory of your project
And then run on device again
.

React Native project can't be open with android emulator

I'm a newbie to react native. I started a new project and followed all the steps. I had Android Studio before and I started the emulator with it. After running npx react-native run-android command I get this error.
**FAILURE: Build failed with an exception.
* What went wrong:
Task 'installDebug' not found in project ':app'.
* Try:
Run gradlew tasks to get a list of available tasks. 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 34s
error Failed to install the app. Make sure you have the Android development environment set up: https://reactnative.dev/docs/environment-setup. Run CLI with --verbose flag for more details.
Error: Command failed: gradlew.bat app:installDebug -PreactNativeDevServerPort=8081
FAILURE: Build failed with an exception.
* What went wrong:
Task 'installDebug' not found in project ':app'.
* Try:
Run gradlew tasks to get a list of available tasks. 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 34s**
Then I ran abd -d command and I get this.
Android Debug Bridge version 1.0.41
Version 29.0.6-6198805
Installed as C:\Users\User\AppData\Local\Android\Sdk\platform-tools\adb.exe
Can you please help me with this?

As said here, you can try running the following command on the root folder of your project:
cd android && ./gradlew installDevDebug && cd .. && react-native run-android --variant=DevDebug
After this your project should run on your Android sucessfully.
If not, open your project with android studio one time, and then recompile with react-native run-android
If even after this all your project doesnt work, make sure you already have the ANDROID_HOME variable on your PATH variables

Command failed: ./gradlew app:installDebug -PreactNativeDevServerPort=8081

MacBook-Air mlaapp % npx react-native run-android
warn The following packages use deprecated "rnpm" config that will stop working from next release:
- react-native-video: https://github.com/react-native-community/react-native-video#readme
Please notify their maintainers about it. You can find more details at https://github.com/react-native-community/cli/blob/master/docs/configuration.md#migration-guide.
info Running jetifier to migrate libraries to AndroidX. You can disable it using "--no-jetifier" flag.
Jetifier found 1232 file(s) to forward-jetify. Using 4 workers...
info Starting JS server...
info Installing the app...
FAILURE: Build failed with an exception.
What went wrong:
Could not initialize class org.codehaus.groovy.runtime.InvokerHelper
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 1s
error Failed to install the app. Make sure you have the Android development environment set up: https://facebook.github.io/react-native/docs/getting-started.html#android-development-environment. Run CLI with --verbose flag for more details.
Error: Command failed: ./gradlew app:installDebug -PreactNativeDevServerPort=8081
FAILURE: Build failed with an exception.
What went wrong:
Could not initialize class org.codehaus.groovy.runtime.InvokerHelper
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 1s
at checkExecSyncError (child_process.js:631:11)
at execFileSync (child_process.js:649:15)
at runOnAllDevices (/Users/varmabiraju/projects/Joshi/MyProjects/mlaapp/node_modules/#react-native-community/cli-platform-android/build/commands/runAndroid/runOnAllDevices.js:94:39)
at buildAndRun (/Users/varmabiraju/projects/Joshi/MyProjects/mlaapp/node_modules/#react-native-community/cli-platform-android/build/commands/runAndroid/index.js:179:41)
at /Users/varmabiraju/projects/Joshi/MyProjects/mlaapp/node_modules/#react-native-community/cli-platform-android/build/commands/runAndroid/index.js:133:12
at processTicksAndRejections (internal/process/task_queues.js:88:5)
at async Command.handleAction (/Users/varmabraju/projects/Joshi/MyProjects/mlaapp/node_modules/react-native/node_modules/#react-native-community/cli/build/index.js:182:9)

Try changing sdk versions in /android/build.gradle
compileSdkVersion = 30
targetSdkVersion = 30

from the comments, it seems that you are not using the gradle version 6.3. can you update your android build to use gradle 6.3 and see if the issue still persists?
another user faced a similar issue and reported this on github. you may want to take a closer look at it here.

This worked for me: Open task manager (of your OS) and kill adb.exe process. Now start adb again, now adb should start normally.

If this is your error
error for nativeDevServerPort
error Failed to install the app. Make sure you have the Android development environment set up: https://reactnative.dev/docs/environment-setup. Run CLI with --verbose flag for more details.
Error: Command failed: gradlew.bat app:installDebug -PreactNativeDevServerPort=8081
gradle 6.2 all zip causing this error for run-android please change or upgrade the distributionUrl version of gradle in
gradle-wrapper.properties to
distributionUrl=https://services.gradle.org/distributions/gradle-6.3-all.zip
Hope this could help you in installing your react-native application in android