private void initUI() {
    myComponent = new JPanel(new BorderLayout());
    JBSplitter splitter = new JBSplitter("AssociationsEditor.dividerProportion", 0.3f);
    myComponent.add(splitter, BorderLayout.CENTER);

    JPanel leftPanel = new JPanel(new BorderLayout());
    leftPanel.setBorder(IdeBorderFactory.createTitledBorder(XPathBundle.message("border.title.project.xslt.files"), false,
                                                            JBInsets.emptyInsets()).setShowLine(false));
    myTree = new Tree();
    myTree.setRootVisible(false);
    myTree.setShowsRootHandles(false);
    leftPanel.add(new JBScrollPane(myTree), BorderLayout.CENTER);
    splitter.setFirstComponent(leftPanel);

    myList = new JBList<>();
    myList.setCellRenderer(new MyCellRenderer());
    myList.setMinimumSize(new Dimension(120, 200));
    myList.getEmptyText().setText(XPathBundle.message("status.text.no.associated.files"));
    JPanel rightPanel = ToolbarDecorator.createDecorator(myList)
      .addExtraAction(new AddAssociationActionWrapper())
      .addExtraAction(new RemoveAssociationAction())
      .disableUpDownActions().disableAddAction().disableRemoveAction().createPanel();
    final IdeaTitledBorder border =
      IdeBorderFactory.createTitledBorder(XPathBundle.message("border.title.associated.files"), false, JBInsets.emptyInsets());
    UIUtil.addBorder(rightPanel, border.setShowLine(false));
    splitter.setSecondComponent(rightPanel);
  }
private void initUI()