addNode method
Adds a node to the explicit membership.
Only valid for GroupBehavior.explicit and GroupBehavior.parent. For GroupBehavior.bounds, use spatial containment instead.
Implementation
void addNode(String nodeId) {
assert(
behavior != GroupBehavior.bounds,
'Cannot add nodes to bounds behavior - use spatial containment',
);
runInAction(() => _nodeIds.add(nodeId));
}