I have a .gif file inside the assets folder like this assets/Files/android.gif. when I try to open the file it throws an exception at the second line
AssetM
Mina, I had the same problem... I had images and an XML file within "assets" and I could read the XML file but not the images. After a couple of hours of frustration I finally found the solution !
I have posted the solution here: Null-pointer issue displaying an image from assets folder Android 2.2 SDK