public int compare(GroupDelta object1, GroupDelta object2) {
final Long id1 = object1.getId();
final Long id2 = object2.getId();
if (id1 == null && id2 == null) {
return 0;
} else if (id1 == null) {
return -1;
} else if (id2 == null) {
return 1;
} else if (id1 < id2) {
return -1;
} else if (id1 > id2) {
return 1;
} else {
return 0;
}
}
@Override
public long getChildId(int groupPosition, int childPosition) {
final GroupDelta child = (GroupDelta) getChild(groupPosition, childPosition);
if (child != null) {
final Long childId = child.getId();
return childId != null ? childId : Long.MIN_VALUE;
} else {
return Long.MIN_VALUE;
}
}