public final EventHandler<? super MouseEvent> getOnClick() {
    return onClick.get();
  }
Creates a new {@link ToolbarItem} which appears like a {@link MenuButton},
using the given {@code text} and {@code graphic} as button menu button content
and the {@code items} as its {@link MenuItem}s.

@param text  the text to be displayed on the {@link ToolbarItem}
@param graphic the graphic to be displayed on the {@link ToolbarItem}
@param items   the items to be displayed in the context-menu of the {@link ToolbarItem}
workbenchfx-core/src/main/java/com/dlsc/workbenchfx/view/controls/ToolbarItem.java