That message is telling you that the MapInputActivty class is abstract, and instantiation will fail should the system try to launch it. The base classes for your app's components don't need to appear in the manifest. Only the concrete subclasses are necessary, so that the system has the appropriate information on the components' capabilities and functionalities. For example, though all of your Activities must be descendents of the Activity class, you wouldn't list the Activity class in the manifest.
Asked in February 2016Viewed 3,598 timesVoted 6Answered 1 times