Multiple Dex Files Defined in Build Config

Have you ever encounter an error like this?

Error:Error converting bytecode to dex:
Cause: com.android.dex.DexException: Multiple dex files define Lnolambda.test/BuildConfig;

Seems like a multi dex issue right? But wait, this is a green field project. I haven't add any dependencies except for Android support library! But i have multiple module though, hmmm maybe it have something to do with it.

After some googling and and "SO searching" i finally stumbled upon this. It turns out the root cause is because i have the same package name in AndroidManifest.xml(s). The SO answer is not marked as answer but it definitely solve my problem.

So based on that and other searching too, this problem can be happen if:

1. Conflict in package naming in AndroidManifest.xml that resulted a conflicted BuildConfig.java
2. Include the same library twice in your classpath
3. And there also some issue regarding Google Play Service dependency too.

Hope this can help anyone with the same issue. That's all from me. Cao 👋