tryChildAtLevel method
similar to getChildAtLevel except will return null if no descendant exists at searchLevel
Implementation
DeepNavigationNode<T>? tryChildAtLevel(int searchLevel) {
if (searchLevel < level) {
throw ArgumentError(
'Cannot get a child of a level higher than my level (Child Level: $searchLevel My Level: $level)!');
}
if (searchLevel == level) {
return this;
}
if (child == null) {
return null;
}
return child!.tryChildAtLevel(searchLevel);
}