private boolean containsStoredCaches(final Collection<Geocache> caches) {
        for (final Geocache cache : caches) {
            if (cache.isOffline()) {
                return true;
            }
        }
        return false;
    }
Menu items which are not at all usable with the current list type should be hidden.
Menu items which are usable with the current list type but not in the current situation should be disabled.
main/src/main/java/cgeo/geocaching/CacheListActivity.java