protected ActivityType getReference() {
        return activityRef.get();
    }
Standard handler implementation which uses a weak reference to its activity. This avoids that activities stay in
memory due to references from the handler to the activity (see Android Lint warning "HandlerLeak")
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Create static private subclasses of this handler class in your activity.
main/src/main/java/cgeo/geocaching/ui/WeakReferenceHandler.java