// Add expand/collapse action to the toolbar.
final ToolBarManager toolBarManager = new ToolBarManager(SWT.FLAT);
final ToolBar toolbar = toolBarManager.createControl(sec);
toolBarManager.add(new ActionDelegateProxy(
new ClusterTreeExpanderAction(
ClusterTreeExpanderAction.CollapseAction.EXPAND,
clustersTree, this.getSearchResult()),
IAction.AS_PUSH_BUTTON));
toolBarManager.add(new ActionDelegateProxy(
new ClusterTreeExpanderAction(
ClusterTreeExpanderAction.CollapseAction.COLLAPSE,
clustersTree, this.getSearchResult()),
IAction.AS_PUSH_BUTTON));