@Nullable
  protected final JComponent createTitlePane() {
    final String description = myChooserDescriptor.getDescription();
    if (StringUtil.isEmptyOrSpaces(description)) return null;

    final JLabel label = new JLabel(description);
    label.setBorder(
        BorderFactory.createCompoundBorder(
            new SideBorder(UIUtil.getPanelBackground().darker(), SideBorder.BOTTOM),
            JBUI.Borders.empty(0, 5, 10, 5)));
    return label;
  }
  public ImplementationViewComponent(PsiElement[] elements, final int index) {
    super(new BorderLayout());

    final Project project = elements.length > 0 ? elements[0].getProject() : null;
    EditorFactory factory = EditorFactory.getInstance();
    Document doc = factory.createDocument("");
    doc.setReadOnly(true);
    myEditor = factory.createEditor(doc, project);
    ((EditorEx) myEditor).setBackgroundColor(EditorFragmentComponent.getBackgroundColor(myEditor));

    final EditorSettings settings = myEditor.getSettings();
    settings.setAdditionalLinesCount(1);
    settings.setAdditionalColumnsCount(1);
    settings.setLineMarkerAreaShown(false);
    settings.setIndentGuidesShown(false);
    settings.setLineNumbersShown(false);
    settings.setFoldingOutlineShown(false);

    myBinarySwitch = new CardLayout();
    myViewingPanel = new JPanel(myBinarySwitch);
    myEditor.setBorder(null);
    ((EditorEx) myEditor).getScrollPane().setViewportBorder(JBScrollPane.createIndentBorder());
    myViewingPanel.add(myEditor.getComponent(), TEXT_PAGE_KEY);

    myBinaryPanel = new JPanel(new BorderLayout());
    myViewingPanel.add(myBinaryPanel, BINARY_PAGE_KEY);

    add(myViewingPanel, BorderLayout.CENTER);

    myToolbar = createToolbar();
    myLocationLabel = new JLabel();
    myCountLabel = new JLabel();

    final JPanel header = new JPanel(new BorderLayout(2, 0));
    header.setBorder(
        BorderFactory.createCompoundBorder(
            IdeBorderFactory.createBorder(SideBorder.BOTTOM),
            IdeBorderFactory.createEmptyBorder(0, 0, 0, 5)));
    final JPanel toolbarPanel = new JPanel(new GridBagLayout());
    final GridBagConstraints gc =
        new GridBagConstraints(
            GridBagConstraints.RELATIVE,
            0,
            1,
            1,
            0,
            0,
            GridBagConstraints.WEST,
            GridBagConstraints.NONE,
            new Insets(0, 2, 0, 0),
            0,
            0);
    toolbarPanel.add(myToolbar.getComponent(), gc);

    setPreferredSize(new Dimension(600, 400));

    update(
        elements,
        new PairFunction<PsiElement[], List<FileDescriptor>, Boolean>() {
          @Override
          public Boolean fun(
              final PsiElement[] psiElements, final List<FileDescriptor> fileDescriptors) {
            if (psiElements.length == 0) return false;
            myElements = psiElements;

            myIndex = index < myElements.length ? index : 0;
            PsiFile psiFile = getContainingFile(myElements[myIndex]);

            VirtualFile virtualFile = psiFile.getVirtualFile();
            EditorHighlighter highlighter;
            if (virtualFile != null)
              highlighter = HighlighterFactory.createHighlighter(project, virtualFile);
            else {
              String fileName = psiFile.getName(); // some artificial psi file, lets do best we can
              highlighter = HighlighterFactory.createHighlighter(project, fileName);
            }

            ((EditorEx) myEditor).setHighlighter(highlighter);

            gc.fill = GridBagConstraints.HORIZONTAL;
            gc.weightx = 1;
            if (myElements.length > 1) {
              myFileChooser =
                  new ComboBox(
                      fileDescriptors.toArray(new FileDescriptor[fileDescriptors.size()]), 250);
              updateRenderer(project);

              myFileChooser.addActionListener(
                  new ActionListener() {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                      int index = myFileChooser.getSelectedIndex();
                      if (myIndex != index) {
                        myIndex = index;
                        updateControls();
                      }
                    }
                  });

              myLabel = new JLabel();
              myLabel.setVisible(false);
              toolbarPanel.add(myFileChooser, gc);
            } else {
              myFileChooser = new ComboBox();
              myFileChooser.setVisible(false);
              myCountLabel.setVisible(false);

              myLabel = new JLabel();
              VirtualFile file = psiFile.getVirtualFile();
              if (file != null) {
                myLabel.setIcon(getIconForFile(psiFile));
                myLabel.setForeground(
                    FileStatusManager.getInstance(project).getStatus(file).getColor());
                myLabel.setText(file.getPresentableName());
                myLabel.setBorder(
                    new CompoundBorder(
                        IdeBorderFactory.createRoundedBorder(),
                        IdeBorderFactory.createEmptyBorder(0, 0, 0, 5)));
              }
              toolbarPanel.add(myLabel, gc);
            }

            gc.fill = GridBagConstraints.NONE;
            gc.weightx = 0;
            toolbarPanel.add(myCountLabel, gc);

            header.add(toolbarPanel, BorderLayout.CENTER);
            header.add(myLocationLabel, BorderLayout.EAST);

            add(header, BorderLayout.NORTH);

            updateControls();
            return true;
          }
        });
  }