Develop Reference

app:compileDebugJavaWithJavac'. > Could not find tools.jar Failed to launch emulator. Reason: No emulators found as an output of `emulator -list-avds`

when I use this command in the terminal:
PS C:\web dev\practice-projects\react-native\myproject> react-native run-android --no-jetifier
I get this whole error:
info JS server already running.
'adb' is not recognized as an internal or external command,
operable program or batch file.
info Launching emulator...
error
Failed to launch emulator. Reason: No emulators found as an output of `emulator -list-avds`.
warn Please launch an emulator manually or connect a device. Otherwise app may fail to launch.
info Installing the app...
Starting a Gradle Daemon, 1 stopped Daemon could not be reused, use --status for details
> Task :app:compileDebugJavaWithJavac FAILED
Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.2/userguide/command_line_interface.html#sec:command_line_warning
14 actionable tasks: 2 executed, 12 up-to-date
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:compileDebugJavaWithJavac'.
> Could not find tools.jar. Please check that C:\Program Files\Java\jre1.8.0_271 contains a valid JDK installation.
* 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 39s
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
My emulator isn't being launched and I have tried multiple fixes. I am getting started in react-native and don't understand the warnings or answers on similar questions. Please help.

There are few ways you can run your app,
Always works - Open the app from android studio. Select Open existing project and select android folder in your app to open the project and run from there after indexing is done.
Not sure would work and not recommended (might need release build) but you can drag your apk file that is auto generated to your simulator to install.
Add this line to gradle.properties file i.e. android/gradle.properties.
org.gradle.java.home=/Library/Java/JavaVirtualMachines/jdk1.8.0_271.jdk/Contents/Home. replace the jdk version name or directory if required.
Note for mac - this is not library folder within your user directory so search them in your main drive location - should be something like machintosh hd
For windows - just replace the path after org.gradle.java.home=. Should be something like C:\\Program Files\\Java\\jdk1.8.0_144

In my case it was because the JAVA_HOME path could not find it.
Close all terminals and open a new one
Find a directory like this on your Mac:
/Library/Java/JavaVirtualMachines/jdk1.8.0_91.jdk/Contents/Home
What may change is the version, but once you have it, it runs in that
path:
export JAVA_HOME = / Library / Java / JavaVirtualMachines /
jdk1.8.0_91.jdk / Contents / Home
IN MY CASE I RUN THIS COMMAND AT THE ROOT OF THE REACT NATIVE PROJECT:
export JAVA_HOME=/Library/Java/JavaVirtualMachines/adoptopenjdk-8.jdk/Contents/Home
AND IT WORKED.

React Native: fail while installing the "app". Error at executing gradlew.bat

​Well, I am trying to install all components to run React Native apps on my computer, but I have been working on this for four days and I always got the same error message:
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
​I reinstalled the components three times, but only some things changed, like the time that jumped from 30 minutes to 3 hours, and the quantity of text that shows on my screen.
​I tried a lot of solutions I found on the internet, like uninstall the global react-native-cli and use .\gradlew clean however it did not work because I got a message saying that "." is not recognized like a command. I really do not know how to correct it...
Bellow, my computer configurations:
System: Windows 7 professional SP1
Processor: Intel Atom CPU D525 #1.80Ghz 1.79GHz
RAM memory: 2,00GB
Type of system: 32-bit operating system
The React Native component versions I installed:
Chocolatey: v0.10.15
Node.js: v12.13.0
Npm: 6.12.0
Yarn: 1.22.5
Python: 2.7.18
JDK 8: 1.8.0_271
Android Studio: 3.6.3
Observations:
I also have Python 3.8 installed
I also tried the command line tools only before the Android Studio IDE
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: Unknown failure: Exception occurred while executing:
android.os.ParcelableException: java.io.IOException: Requested internal only, but not enough space
at android.util.ExceptionUtils.wrap(ExceptionUtils.java:34)
at com.android.server.pm.PackageInstallerService.createSession(PackageInstallerService.java:413)
at com.android.server.pm.PackageManagerShellCommand.doCreateSession(PackageManagerShellCommand.java:2418)
at com.android.server.pm.PackageManagerShellCommand.runInstall(PackageManagerShellCommand.java:907)
at com.android.server.pm.PackageManagerShellCommand.onCommand(PackageManagerShellCommand.java:158)
at android.os.ShellCommand.exec(ShellCommand.java:103)
at com.android.server.pm.PackageManagerService.onShellCommand(PackageManagerService.java:22015)
at android.os.Binder.shellCommand(Binder.java:634)
at android.os.Binder.onTransact(Binder.java:532)
at android.content.pm.IPackageManager$Stub.onTransact(IPackageManager.java:2809)
at com.android.server.pm.PackageManagerService.onTransact(PackageManagerService.java:4070)
at android.os.Binder.execTransact(Binder.java:731)
Caused by: java.io.IOException: Requested internal only, but not enough space
at com.android.internal.content.PackageHelper.resolveInstallVolume(PackageHelper.java:232)
at com.android.internal.content.PackageHelper.resolveInstallVolume(PackageHelper.java:148)
at com.android.internal.content.PackageHelper.resolveInstallVolume(PackageHelper.java:163)
at com.android.server.pm.PackageInstallerService.createSessionInternal(PackageInstallerService.java:510)
at com.android.server.pm.PackageInstallerService.createSession(PackageInstallerService.java:411)
... 10 more
* 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 1h 47m 4s
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
Note: C:\Users\myusername\Desktop\appproject1\android\app\src\debug\java\com\appproject1\ReactNativeFlipper.java uses or overrides a deprecated API.
C:\Users\myusername\Desktop\appproject1>
​ I apologize for not being able to give you more information. I ask you to help me, please.
Edit:
I would like to give some tips about problems I got when trying to use react-native:
Low space on the smartphone. Please try to install something in the store, if you cannot do it, you need to free some space.
Some problems could be solved only by trying to run the project by Android Studio, please try it too.
Cache may be your problem. Try it inside the project folder:
cd android
gradlew clean
after it, run the project again returning to the project folder using cd ..:
cd ..
react-native run-android

Issue:
> Caused by: java.io.IOException: Requested internal only, but not enough space
solution -1-
replace
android:installLocation="internalOnly"
with
android:installLocation="preferExternal"
solution -2-
make some space on the device / emulator

React Native run-android Only works on the first build

The first time I run my react-native app the emulator works (using Android Studio Galaxy Nexus). However, when I close the emulator and try again I get the errors below:
PS C:\Users\4chea\pexhouseV2> react-native run-android
info Running jetifier to migrate libraries to AndroidX. You can disable it using "--no-jetifier" flag.
Jetifier found 1197 file(s) to forward-jetify. Using 8 workers...
info Starting JS server...
info Launching emulator...
error Failed to launch emulator. Reason: Emulator exited before boot..
warn Please launch an emulator manually or connect a device. Otherwise app may fail to launch.
info Installing the app...
> Task :app:stripDebugDebugSymbols UP-TO-DATE
Compatible side by side NDK version was not found.
> Task :app:installDebug FAILED
Skipping device 'emulator-5554' (emulator-5554): Device is OFFLINE.
Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.2/userguide/command_line_interface.html#sec:command_line_warnings
160 actionable tasks: 2 executed, 158 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 24s
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
My emulator is open while this happens and says "failed to connect to metro server"

This here tells you the problem.
info Launching emulator...
error Failed to launch emulator. Reason: Emulator exited before boot..
warn Please launch an emulator manually or connect a device. Otherwise app may fail to launch.
Something is wrong with your emulator. Try rebooting your system. If that doesn't work, try making a new emulator and see if that one works better. Also, I would turn off the Quickstart feature on your emulator - it may ask you as you shut it down if you want to save its memory state for faster boot times. I've had issues with that in the past similar to this.
Let me know if that changes anything. Good luck.

Failed to launch emulator. Reason: Emulator exited before boot en React Native when react-native run-android

I am installing React Native according to this website https://medium.com/#leonardobrunolima/react-native-tips-setting-up-your-development-environment-for-windows-d326635604ea, it's very useful until I run the command react-native run-android, this is the error I receive:
info Running jetifier to migrate libraries to AndroidX. You can disable it using "--no-jetifier" flag.
Jetifier found 864 file(s) to forward-jetify. Using 8 workers...
info Starting JS server...
info Launching emulator...
error Failed to launch emulator. Reason: Emulator exited before boot..
> Task :app:transformNativeLibsWithMergeJniLibsForDebug FAILED
Deprecated Gradle features were used in this build, making it incompatible with Gradle 6.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/5.5/userguide/command_line_interface.html#sec:command_line_warnings
24 actionable tasks: 4 executed, 20 up-to-date
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:transformNativeLibsWithMergeJniLibsForDebug'.
> Could not read path 'C:\JesusApp\android\app\build\intermediates\transforms\mergeJniLibs\debug\0\lib\x86_64'.
* 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 7s
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.bat app:installDebug -PreactNativeDevServerPort=8081
FAILURE: Build failed with an exception.
* What went wrong:
Execution failed for task ':app:transformNativeLibsWithMergeJniLibsForDebug'.
> Could not read path 'C:\JesusApp\android\app\build\intermediates\transforms\mergeJniLibs\debug\0\lib\x86_64'.
* 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 7s
at checkExecSyncError (child_process.js:629:11)
at execFileSync (child_process.js:647:13)
at runOnAllDevices (C:\JesusApp\node_modules\#react-native-community\cli-platform-android\build\commands\runAndroid\runOnAllDevices.js:94:39)
at process._tickCallback (internal/process/next_tick.js:68:7)
My node version is 10, and I am working on Windows, please help, thank you.

I succeeded by doing the following steps:
Open android studio > AVD Manager > Actions (click the bottom icon) > Select Cool Boot Now.

Check your config and environment setup with instructions here, be very careful with pathes set up. Check the $PATH from your IDE's terminal.
check in the AVD that a particular Android OS is selected and installed for a virtual device you use (in my case it was not, I had yellow warning exclaim sign in an "Actions" column in an AVD's devices list).
Have your Gradle updated to at least 6.6 in the
android/gradle/wrapper/gradle-wrapper.properties
On Ubuntu after run I had to "push" switch-on button on the virtual device.
Finally, I got it up and running both on Windows 10 and Ubuntu 20.04 LTS with Android 30.

This might be the insufficient space in your machine or AVD or the mismatch in the configurations.
So, do the following steps to resolve this issue.
Verify that the environment variables are set for SDK path and adb.
Clean the project by Build -> Clean Project
Clean AVD by Open android studio > AVD Manager > Actions (click the bottom icon) > Select Cool Boot Now.

First start the android emulator on Android Studio, then execute the react-native run-android. If it doesn´t work go to android studio and do "Build -> Clean Project"

For me running
adb kill-server
and
adb start-server
worked
I also runned killall 9 node before that but it was not enough. MacOS asks for saving last state before restart also Android emulator asks before quiting it. Maybe the problem happens because saving a bad state and trying to start from that bad state. Not sure but I suspect one of these.

In my case, I've to wipe data on the virtual device.
Android Studio -> AVD -> Actions (↓) -> Wipe Data

I faced similar problem when executing my react-native code on Android Physical device. I am not sure if my solution will help.
We all know that ADB requires authorization from an Android device in order to communicate with it. It’s only by allowing the USB debugging and validating the computer’s RSA key fingerprint that we let the ADB daemon connect to our phone and control it. This is a security feature.
My phone was connected with USB and on changing USB Configuration on device, my phone gave me another prompt "Allow USB debugging?" Image available for reference. I got solution on reallow USB debugging

I had the same problem, only check the developer options and enable the debug by usb, on the device

For me, the problem ended up being quite simple. Working in react-native, I was running the following command from the terminal 'npx react-native run-android' in VS CODE. Though the emulator would run fine when started from Android Studios, I received the above error when running from the terminal in VS Code.
Solution: Run VS Code as Administrator. (or your terminal in general)

worked for me - there is not enough space on disk, Check that there is enough space on disk(where is the emulator was installed).

In my case, cool boot and wipe data didn't work. I just uninstall the virtual device and reinstall it and then it works for me.

Worked for me - reload system or clean system/android cache ./android/avd

Deleting the file app\build\intermediates\signing_config\debug\out\signing-config.json worked for me.

Could not create service of type ScriptPluginFactory using BuildScopeServices.createScriptPluginFactory() react-native. How to fix?

I have the template code for my "Helloworld" app written in javascript and react-native on Windows. I connected my android emulator and wanted to launch the app on it. The following happens when I run "react-native run-android" command. Node.js opens as a separate window and it's written "Loading dependency graph, done". However, in the terminal window, there is following error message:
>User helloworld $ react-native run-android
Starting JS server...
Building and installing the app on the device (cd android && gradlew.bat installDebug)...
FAILURE: Build failed with an exception.
>*What went wrong:
Could not create service of type ScriptPluginFactory using
BuildScopeServices.createScriptPluginFactory().
>Could not create service of type PluginResolutionStrategyInternal using BuildScopeServices.createPluginResolutionStrategy().
>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
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
Command failed: gradlew.bat installDebug
Error: Command failed: gradlew.bat installDebug
at checkExecSyncError (child_process.js:616:11)
at Object.execFileSync (child_process.js:634:13)
at runOnAllDevices (C:\Users\User\helloworld\node_modules\react-native\local-cli\runAndroid\runAndroid.js:299:19)
at buildAndRun (C:\Users\User\helloworld\node_modules\react-native\local-cli\runAndroid\runAndroid.js:135:12)
at isPackagerRunning.then.result (C:\Users\User\helloworld\node_modules\react-native\local-cli\runAndroid\runAndroid.js:65:12)
at process._tickCallback (internal/process/next_tick.js:68:7)
-Concerning whether emulator is connected:
$ adb devices
List of devices attached
emulator-5554 device
(Works similarly for my Android smartphone). USB debugging is enabled.
-Concerning what I have tried to solve the problem:
My user is set as administrator.
I had JDK11.0.1 version. I installed JDK1.8.0_201 and it is now set as my java version.
User helloworld $ java -version
java version "1.8.0_201"
I created ".gradle" folder in my project's directory in case there are problems with accessing/creating this kind of folder.
-I specified the path for sdk.dir in local.properties file
-My OS is Windows 8.1. Gradle's version is 4.7.
-I have installed Android Studio, JDK8 and 11.
-I am using GitBash for the terminal purposes.
-I have the following system's environment variables:
ANDROID_HOME = c:\Users\User\AppData\Local\Android\Sdk
GRADLE_HOME = C:\Users\User.gradle\wrapper\dists\gradle-4.7-all\4cret0dgl5o3b21weaoncl7ys\gradle-4.7
JAVA_HOME = C:\Program Files\Java\jdk1.8.0_201
Path = C:\Program Files (x86)\Common Files\Oracle\Java\javapath;C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files\Git\cmd;.\Plugins;C:\Users\User\AppData\Local\Programs\Python\Python37-32;C:\Program Files\nodejs\;c:\Users\User\AppData\Local\Android\Sdk\platform-tools;C:\Users\User\AppData\Local\Android\Sdk\platform-tools;%GRADLE_HOME%\bin;%JAVA_HOME%\bin
In case you are interested what was in the question before:
My initial problem was that there just was not any error shown, but still nothing was launched on the emulator. I went around that by putting my project's "android" folder into Android Studio and it launched the app on my smartphone. However, when I introduced small changes to App.js, the project could not be updated due to some unknown error, and I couldn't reopen it as a new project. So I had to solve this problem by trying to run the app by using "react-native run-android" through terminal, and now I'm at this state of the problem.

Mmmm... when you run react-native run-android on the console, 1 it should check if you have the android sdk's, second it should compile some things, and third, it should start metro bundler in ANOTHER console . The "Loading dependency graph, done" should appear on that OTHER console, while the main console is gonna still compile for about a minute or even more... then it's gonna launch the intent and open the app. Sometimes it just displays a blank screen after the first load, so you should exit the app and delete it from recents, and reopen the app
Post screenshots, it seems like you only see that secondary console while the main console is not displaying (?)

Do you want to run a react-native or purely java application for which you must have used Android studio?
If for the studio app: you must enable the developer's options from your phone for enabling that check this:
https://www.samsung.com/uk/support/mobile-devices/how-do-i-turn-on-the-developer-options-menu-on-my-samsung-galaxy-device/