如何在GWT中取消选择项目？

Question

我目前正在开发一个GWT应用程序，我遇到一个问题。当我在某个选项卡上选择一个项目，然后我转到其他选项卡，当我返回时，仍然选择了所选项目。但是当我回到该选项卡上时，我不希望选择项目。以下是我的一些标签中的一段代码：

 protected void onRender(Element parent, int index) {
        super.onRender(parent, index);

        setWidth("100%");

        BorderLayoutData messageLayout = new BorderLayoutData(LayoutRegion.NORTH, 0.06f);
        messageLayout.setMargins(new Margins(5));
        Text welcomeMessage = new Text();
        welcomeMessage.setText(MSGS.topicTabItemMessage());
        add(welcomeMessage, messageLayout);

        LayoutContainer tables = new LayoutContainer(new BorderLayout());
        BorderLayoutData tablesLayout = new BorderLayoutData(LayoutRegion.CENTER);
        tablesLayout.setMargins(new Margins(0, 5, 0, 5));
        tablesLayout.setMinSize(250);
        add(tables, tablesLayout);

        BorderLayoutData topicLayout = new BorderLayoutData(LayoutRegion.WEST, 0.5f);
        topicTable = new TopicsTable(currentSession);
        topicTable.setBorders(false);
        topicLayout.setMargins(new Margins(0, 5, 0, 0));
        topicLayout.setSplit(true);
        topicTable.addSelectionChangedListener(new SelectionChangedListener<GwtTopic>() {

            @Override
            public void selectionChanged(SelectionChangedEvent<GwtTopic> selectedTopic) {
                refreshButton.enable();
                metricsTable.refresh(selectedTopic.getSelectedItem());
            }
        });
        tables.add(topicTable, topicLayout);

        BorderLayoutData metricLayout = new BorderLayoutData(LayoutRegion.CENTER);
        metricLayout.setMargins(new Margins(0, 0, 0, 5));
        metricsTable = new MetricsTable(currentSession, MetricsTable.Type.TOPIC);
        metricsTable.addSelectionListener(new SelectionChangedListener<GwtHeader>() {

            @Override
            public void selectionChanged(SelectionChangedEvent<GwtHeader> se) {
                if (!se.getSelection().isEmpty()) {
                    queryButton.enable();                
                } else {
                    queryButton.disable();
                }
            }
        });
        tables.add(metricsTable, metricLayout);

        BorderLayoutData queryButtonLayout = new BorderLayoutData(LayoutRegion.SOUTH, 0.1f);
        queryButtonLayout.setMargins(new Margins(5));
        queryButton = new Button(MSGS.topicTabItemQueryButtonText(), new KapuaIcon(IconSet.SEARCH), new SelectionListener<ButtonEvent>() {

            @Override
            public void componentSelected(ButtonEvent ce) {
                GwtTopic topic = topicTable.getSelectedTopic();
                List<GwtHeader> metrics = metricsTable.getSelectedMetrics();
                resultsTable.refresh(topic, metrics);
            }
        });
        queryButton.disable();
        TableLayout queryButtonTL = new TableLayout();
        queryButtonTL.setCellPadding(0);
        LayoutContainer queryButtonContainer = new LayoutContainer(queryButtonTL);

        refreshButton = new Button(MSGS.refresh(), new KapuaIcon(IconSet.REFRESH), new SelectionListener<ButtonEvent>() {

            @Override
            public void componentSelected(ButtonEvent ce) {

                GwtTopic topic = topicTable.getSelectedTopic();
                List<GwtHeader> metrics = metricsTable.getSelectedMetrics();
                resultsTable.refresh(topic, metrics);
                metricsTable.refresh();
            }
        });
        refreshButton.disable();
        toolbar = new ToolBar();
        toolbar.add(queryButton);
        toolbar.add(new SeparatorToolItem());
        toolbar.add(refreshButton);

        queryButtonContainer.add(toolbar);
        tables.add(queryButtonContainer, queryButtonLayout);

        BorderLayoutData resultsLayout = new BorderLayoutData(LayoutRegion.SOUTH, 0.5f);
        resultsLayout.setSplit(true);

        TabPanel resultsTabPanel = new TabPanel();
        resultsTabPanel.setPlain(true);
        resultsTabPanel.setBorders(false);
        resultsTabPanel.setBodyBorder(false);

        resultsTable = new ResultsTable(currentSession);
        TabItem resultsTableTabItem = new TabItem(MSGS.resultsTableTabItemTitle(), new KapuaIcon(IconSet.TABLE));
        resultsTableTabItem.setLayout(new FitLayout());
        resultsTableTabItem.add(resultsTable);
        resultsTabPanel.add(resultsTableTabItem);

        add(resultsTabPanel, resultsLayout);
    }

如何解决这个问题？提前谢谢。