Unable to execute dex: Multiple dex files define

Question

Whats worng ?why i have this problems?

Unable to execute dex: Multiple dex files define Lcom/nineoldandroids/animation/Animator$AnimatorListener;

and

Unable to execute dex: Multiple dex files define Lcom/nineoldandroids/animation/Animator$AnimatorListener;

Answer 1

Are you using android library (another library project) that has the a .jar library named the same as another .jar in your project but with different sha1 (or different sizes) ?

if so try to use only 1 of the duplicated library and then clean and rebuild.

also check this question it may be helpful Unable to execute dex: Multiple dex files define Lcom/myapp/R$array;