updateFlatNodes method

void updateFlatNodes()

Rebuilds the flatNodes list by traversing the tree starting from the root.

Implementation

void updateFlatNodes() {
  flatNodes = [];
  _flatten(widget.root, 0, [], true, flatNodes);
  if (flatNodes.isNotEmpty) {
    selectedIndex = selectedIndex.clamp(0, flatNodes.length - 1);
  } else {
    selectedIndex = 0;
  }
}