// Load all countries
List<Feature> countries = GeoJSONReader.loadData(this, "data/countries.geo.json");
List<Marker> countryMarkers = MapUtils.createSimpleMarkers(countries);
// But only combine Germany, France, and Ireland
MultiMarker multiMarker = new MultiMarker();
for (Marker marker : countryMarkers) {
if (specialIDs.contains(marker.getId())) {
multiMarker.addMarkers(marker);
}
}
map.addMarkers(multiMarker);
// Zoom in, and center around MultiMarker
map.zoomToLevel(4);
map.panTo(multiMarker.getLocation());
}