deleteSelected method
Deletes the selected object.
Implementation
bool deleteSelected() {
if (_selectedObjectIds.isEmpty) return false;
_remember();
final ids = Set<String>.from(_selectedObjectIds);
final before = _objects.length;
_objects.removeWhere(
(object) =>
object.id != null && ids.contains(object.id) && !object.locked,
);
final removed = before != _objects.length;
if (!removed) {
_undoStack.removeLast();
return false;
}
_selectedObjectIds.removeWhere((id) => objectById(id) == null);
render();
_emitSelect();
_emitChange();
return true;
}