How to triger animation when ar marker tracking is lost?

Hi to everone,
i am new to the unity3d.but i am developing AR marker using unity3d in android.can anyone please tell how to trigger animation in unity3d when we lost ar marker?
please help me

Same issue like this Qualcomm-Unity ?

yaa robhuhn.i am able to the ar marker in unity3d.also doing arugmented reality.But i want solution for the above question?plz help me

If you follow the link Robhuhn supplied all the way it would take you to the Qualcomm forums where there are code examples on how to pull this off. Read through those posts, and if you have a specific question on one of those code examples I’ll be happy to help.

thankx robhuhn,Joshua_Falner.I find some solution.thank u very much