sendBackward method
void
sendBackward()
Implementation
void sendBackward() {
final selection = _selected.toList();
if (selection.length == 1) {
final key = selection.first;
final index = nodes.indexWhere((e) => e.key == key);
if (index == -1) return;
if (index == 0) return;
final current = nodes[index];
nodes.removeAt(index);
nodes.insert(index - 1, current);
notifyListeners();
}
}