private LayoutContainer createContentContainer() {
    LayoutContainer contentContainer = new LayoutContainer();
    contentContainer.setBorders(false);
    contentContainer.setSize(340, 170);
    HBoxLayout tabbarContainerLayout = new HBoxLayout();
    tabbarContainerLayout.setHBoxLayoutAlign(HBoxLayoutAlign.TOP);
    contentContainer.setLayout(tabbarContainerLayout);

    LayoutContainer contentItemsContainer = new LayoutContainer();
    contentItemsContainer.setBorders(true);
    contentItemsContainer.setWidth(230);
    contentItemsContainer.setHeight(160);
    contentItemsContainer.setLayout(new FitLayout());
    contentItemsContainer.setStyleAttribute("backgroundColor", "white");
    // overflow-auto style is for IE hack.
    contentItemsContainer.addStyleName("overflow-auto");

    TreeStore<BeanModel> deviceContentTreeStore = new TreeStore<BeanModel>();
    deviceContentTree = TreePanelBuilder.buildDeviceContentTree(deviceContentTreeStore);
    contentItemsContainer.add(deviceContentTree);

    LayoutContainer buttonsContainer = new LayoutContainer();
    buttonsContainer.setSize(110, 160);
    buttonsContainer.setBorders(false);
    buttonsContainer.setLayout(new RowLayout(Orientation.VERTICAL));

    Button addCommandBtn = new Button("Add command");
    addCommandBtn.addSelectionListener(new AddCommandListener());

    Button addSensorBtn = new Button("Add sensor");
    addSensorBtn.addSelectionListener(new AddSensorListener());

    Button addSwitchBtn = new Button("Add switch");
    addSwitchBtn.addSelectionListener(new AddSwitchListener());

    Button addSliderBtn = new Button("Add slider");
    addSliderBtn.addSelectionListener(new AddSliderListener());

    Button deleteBtn = new Button("Delete");
    deleteBtn.addSelectionListener(new DeleteContentListener());

    buttonsContainer.add(addCommandBtn, new RowData(110, -1, new Margins(5)));
    buttonsContainer.add(addSensorBtn, new RowData(110, -1, new Margins(5)));
    buttonsContainer.add(addSwitchBtn, new RowData(110, -1, new Margins(5)));
    buttonsContainer.add(addSliderBtn, new RowData(110, -1, new Margins(5)));
    buttonsContainer.add(deleteBtn, new RowData(110, -1, new Margins(5)));

    contentContainer.add(contentItemsContainer);
    contentContainer.add(buttonsContainer);
    return contentContainer;
  }