Bug 316195 Improve "Show view" dialog
bundles/org.eclipse.e4.ui.workbench.swt/src/org/eclipse/e4/ui/internal/workbench/swt/handlers/ShowViewHandler.java
public static final String VIEWS_SHOW_VIEW_PARM_ID = "org.eclipse.ui.views.showView.viewId"; 
	@Execute
	public void execute(@Named(IServiceConstants.ACTIVE_SHELL) Shell shell,
			MApplication application, EPartService partService,
			@Optional @Named(VIEWS_SHOW_VIEW_PARM_ID) String viewId) {
		if (viewId != null) {
			partService.showPart(viewId, PartState.ACTIVATE);
			return;
		}
		final ShowViewDialog dialog = new ShowViewDialog(shell, application);
		dialog.open();
		if (dialog.getReturnCode() != Window.OK)
			return;
		for (MPartDescriptor descriptor : dialog.getSelection()) {
			partService.showPart(descriptor.getElementId(), PartState.ACTIVATE);
		}
	}
}