Unable to execute dex: Multiple dex files define L

Question

Since updating to ADT 14 I can no longer build my project. It was building fine prior to updating.

The error:

[2011-10-23 16:23:29 - Dex Loader] Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;
[2011-10-23 16:23:29 - myProj] Conversion to Dalvik format failed: Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;

Similar issues have been reported and I have tried the suggestions there including

• Restarting Eclipse.
• Cleaning the project and rebuild - Disable "Project->Build Automatically" option, then "Clean" and "Build" project, then try to run. reset "Build Automatically" option to On
• Re-installing the Android Developer Tools
• Re-installing Eclipse (updated to the latest version 3.7.1)
• Created a new project importing from the file system
• Created a new project from subversion.

Answer 1

You have probably installed r14, this error may have been caused due to the platform tools update, you have to re-install your sdk

Answer 2

Go to Project/properties and Java Build Path and unchecked the Android Private Libraries.

Done

Answer 3

I have several library projects with the same package name specified in the AndroidManifest (so no duplicate field names are generated by R.java). I had to remove any permissions and activities from the AndroidManifest.xml for all library projects to remove the error so Manifest.java wasn't created multiple times. Hopefully this can help someone.

Answer 4

Modify your eclipse.ini file and set the maximum memory parameter to

-Xmx1024m

Then restart your computer.

It worked for me.

Answer 5

I converted a non-library project to a library project, but it had a previously built jar file in the libs folder. Removing this jar file caused this error to go away.

Answer 6

As others have mentioned, this occurs when you have multiple copies of the same class in your build path - including bin/ in your classpath is one way to guarantee this problem.

For me, this occurred when I had added android-support-v4.jar to my libs/ folder, and somehow eclipse added a second copy to bin/classes/android-support-v4.jar.

Deleting the extra copy in bin/classes solved the problem - unsure why Eclipse made a copy there.

You can test for this with

grep -r YourOffendingClassName YourApp | grep jar