onHold(event) {
    const pointer = this.getPointer(event.center);
    const multiselect = this.selectionHandler.options.multiselect;

    this.checkSelectionChanges(pointer, multiselect);

    this.selectionHandler.commitAndEmit(pointer, event);
    this.selectionHandler.generateClickEvent("click", event, pointer);
    this.selectionHandler.generateClickEvent("hold", event, pointer);
  }
handle long tap event: multi select nodes
@param {Event} event
@private