【Android】解決 Unable to execute dex: Multiple dex files define

[方法一] I had the same problem, quite weird because it was happening only when using Eclipse (but it was OK with Ant). This is how I fixed it: Right click on the Project Name Select Build Path -> Configure Build Path In Java Build Path, go to the tab Order and Export Uncheck your .jar library Only sometimes: In Order and Export tab I did not have any jar library there, so I have unchecked Android Private Libraries item. Now my project is running. [方法二] NON OF THE ABOVE METHODE WORKED FOR ME BUT MINE IS WORKED LIKE A CHARM! The problem happens when user builds the dependent library with eclipse. So to get the solution Step 1: Delete the library (like support library project v4 or v13) from Eclipse with delete workspace source permanantly Step 2: Re import the library and include it to your project Step 3: Clean and Rebuild DONE!   ref: http://stackoverflow.com/questions/7870265/unable-to-execute-dex-multiple-dex-files-define-lcom-myapp-rarray?page=1&tab=votes#tab-top