New project > Task :app:compileDebugJavaWithJavac FAILED

[kot7kz]

Hey guys, im new to react native and i'm trying to make an app that is connected to phone via bluetooth so i tried using the react-native-ble-plx.

I created a new project so i could try to run the demo, followed all the tutorials of "react-native getting started", and even the installation guide of ble-plx with all the jetifier commands.

In the end i can't get past this error:

Task :app:compileDebugJavaWithJavac 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/5.4.1/userguide/command_line_interface.html#sec:command_line_warnings
23 actionable tasks: 2 executed, 21 up-to-date
C:\Users\stron\Documents\HexoBlue\android\app\src\main\java\com\hexoblue\MainApplication.java:19: error: cannot find symbol
return BuildConfig.DEBUG;
^
symbol: variable BuildConfig
C:\Users\stron\Documents\HexoBlue\android\app\src\main\java\com\hexoblue\MainApplication.java:55: error: cannot find symbol
if (BuildConfig.DEBUG) {
^
symbol: variable BuildConfig
location: class MainApplication
C:\Users\stron\Documents\HexoBlue\android\app\src\main\java\com\hexoblue\MainApplication.java:55: error: illegal start of type
if (BuildConfig.DEBUG) {
^
3 errors

FAILURE: Build failed with an exception.

• What went wrong:
  Execution failed for task ':app:compileDebugJavaWithJavac'.

Compilation failed; see the compiler error output for details.

• 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
C:\Users\stron\Documents\HexoBlue\android\app\src\main\java\com\hexoblue\MainApplication.java:19: error: cannot find symbol
return BuildConfig.DEBUG;
^
symbol: variable BuildConfig
C:\Users\stron\Documents\HexoBlue\android\app\src\main\java\com\hexoblue\MainApplication.java:55: error: cannot find symbol
if (BuildConfig.DEBUG) {
^
symbol: variable BuildConfig
location: class MainApplication
C:\Users\stron\Documents\HexoBlue\android\app\src\main\java\com\hexoblue\MainApplication.java:55: error: illegal start of type
if (BuildConfig.DEBUG) {
^
3 errors

FAILURE: Build failed with an exception.

• What went wrong:
  Execution failed for task ':app:compileDebugJavaWithJavac'.

Compilation failed; see the compiler error output for details.

• 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:603:11)
at execFileSync (child_process.js:621:15)
at runOnAllDevices (C:\Users\stron\Documents\HexoBlue\node_modules\@react-native-community\cli-platform-android\build\commands\runAndroid\runOnAllDevices.js:74:39)
at buildAndRun (C:\Users\stron\Documents\HexoBlue\node_modules\@react-native-community\cli-platform-android\build\commands\runAndroid\index.js:158:41)
at C:\Users\stron\Documents\HexoBlue\node_modules\@react-native-community\cli-platform-android\build\commands\runAndroid\index.js:125:12
at processTicksAndRejections (internal/process/task_queues.js:93:5)
at async Command.handleAction (C:\Users\stron\Documents\HexoBlue\node_modules\react-native\node_modules\@react-native-community\cli\build\cliEntry.js:160:7)

please help