setActiveChildIndex method
Implementation
void setActiveChildIndex(int idx) {
if (children != null) {
_activeChildIndex = min(children!.length, max(0, idx));
for (int i = 0; i < children!.length; i++) {
var child = children![i];
bool cv = i != (_activeChildIndex - 1);
if (child is ActorNode) {
child.collapsedVisibility = cv; // Setter
}
}
}
}