final Category[] categories = ContactDatabase.get().queryCategories();
List<String> categoryNames = new ArrayList<String>();
for (Category category : categories) {
categoryNames.add(category.getDisplayName());
}
SelectionCell categoryCell = new SelectionCell(categoryNames);
Column<ContactInfo, String> categoryColumn = new Column<ContactInfo, String>(categoryCell) {
@Override
public String getValue(ContactInfo object) {
return object.getCategory().getDisplayName();
}