IWorkbenchPage activePage = PlatformUI.getWorkbench().getActiveWorkbenchWindow().getActivePage();IViewReference viewReference = activePage.findViewReference(ContentTreeViewer.ID);if (viewReference == null) {try {activePage.showView(ContentTreeViewer.ID);} catch (PartInitException e) {LOGGER.error("OpenSlipView Error : " , e);}} else {activePage.hideView(viewReference);}