equalSubItems method
Implementation
bool equalSubItems(HasDatabaseSubItems<T>? item) {
if (item == null) return false;
if (subItems.length != item.subItems.length) return false;
for (var i = 0; i < subItems.length; i++) {
if (!subItems[i].equals(item.subItems[i])) return false;
}
return true;
}