after a long search I couldn\'t find any appropriate solution. I have a Android-Library Project with nearly all code for the application. From the main activity in the libra
In your new project, you could use a different name, instead of AndroidActivity. If you don't want to do that, the second AndroidActivity's fully qualified name in the manifest file should solve your problem. You are perhaps messing up with packages a little bit, somewhere.
activity android:name="de.app.library.activities.AndroidActivity"
should be
activity android:name="de.app.free.activities.AndroidActivity"
I meant, the AndroidActivity. In some way, your are picking up the wrong activity class from the wrong package.