handleClearSelection method Null safety
- ClearSelectionEvent event
 
protected">@protected
    Removes the selection of all selectables this delegate manages.
Implementation
@protected
SelectionResult handleClearSelection(ClearSelectionEvent event) {
  for (final Selectable selectable in selectables) {
    dispatchSelectionEventToChild(selectable, event);
  }
  currentSelectionEndIndex = -1;
  currentSelectionStartIndex = -1;
  return SelectionResult.none;
}