React Native Duplicate resources

Question

After upgrading to React Native 0.57 i am facing an issue when genrating APK in react-native-router-flux.when executing the .\gradlew assembleRelease i get below error :-

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:mergeReleaseResources'.
> [drawable-mdpi-v4/node_modules_reactnativerouterflux_images_back_chevron] 
R:\Workings\lisecapps\androidrepo\test-react- 
native\venutest\android\app\src\main\res\drawable- 
mdpi\node_modules_reactnativerouterflux_images_back_chevron.png      
[drawable-mdpi-v4/node_modules_reactnativerouterflux_images_back_chevron] 
R:\Workings\lisecapps\androidrepo\test-react- 
emirnative\venutest\android\app\build\generated\res\react\release\drawable- 
mdpi-v4\node_modules_reactnativerouterflux_images_back_chevron.png: Error: 
Duplicate resources
[drawable-mdpi-v4/node_modules_reactnativerouterflux_images_menu_burger] 
R:\Workings\lisecapps\androidrepo\test-react-nat 
ive\venutest\android\app\src\main\res\drawable- 
mdpi\node_modules_reactnativerouterflux_images_menu_burger.png        
[drawable-mdpi-v4/node_modules_reactnativerouterflux_images_menu_burger] 
R:\Workings\lisecapps\androidrepo\test-react- 
native\venutest\android\app\build\generated\res\react\release\drawable-mdpi- 
v4\node_modules_reactnativerouterflux_images_menu_burger.png: Error: 
Duplicate resources

I tried the following to resolve but still same error :-

• Tried to create script as said in the first answer here to avoid duplicate copying of asset images.
• Deleted the whole app/build folder

Answer 1

You need remove generated resources/drawable and generate again.

rm -rf android/app/src/main/res/drawable-*
react-native bundle --platform android --dev false --entry-file index.js --bundle-output android/app/src/main/assets/index.android.bundle --assets-dest android/app/src/main/res/

And compile android again react-native run-android

Answer 2

react.gradle automatically build your javascript and copy any resources imported inside your javascript to the build folder so make sure to NOT call react-native bundle manually and delete any files or folder as src/main/res/drawable-* and src/main/assets/*.bundle and have the following changes into your app/bundle.gradle

project.ext.react = [
  entryFile      : "index.js", // or index.android.js
  bundleInRelease: true,
  bundleInDebug: true
]

apply from: "../../node_modules/react-native/react.gradle"

Note: please notice that some react-native versions have a problem with the local cli.js please make sure to upgrade to a newer version or try adding the following config

 project.ext.react = [
    // ...
    cliPath: "node_modules/react-native/local-cli/cli.js"
 ]