@Nullable
  @Override
  protected JComponent createCenterPanel() {
    JPanel mainPanel = new JPanel(new BorderLayout());

    JBSplitter splitPane = new JBSplitter(0.3f);
    splitPane.setSplitterProportionKey(getSplitterProportionKey());

    splitPane.setFirstComponent(createMasterView());
    splitPane.setSecondComponent(createDetailView());

    mainPanel.add(splitPane, BorderLayout.CENTER);

    return mainPanel;
  }
  @Override
  protected JComponent createCenterPanel() {
    final int selectionMode =
        myAllowMultipleSelections
            ? ListSelectionModel.MULTIPLE_INTERVAL_SELECTION
            : ListSelectionModel.SINGLE_SELECTION;
    myList.setSelectionMode(selectionMode);
    if (myUseIdeaEditor) {
      EditorColorsScheme scheme = EditorColorsManager.getInstance().getGlobalScheme();
      myList.setFont(scheme.getFont(EditorFontType.PLAIN));
      Color fg =
          ObjectUtils.chooseNotNull(scheme.getDefaultForeground(), UIUtil.getListForeground());
      Color bg =
          ObjectUtils.chooseNotNull(scheme.getDefaultBackground(), UIUtil.getListBackground());
      myList.setForeground(fg);
      myList.setBackground(bg);
    }

    new DoubleClickListener() {
      @Override
      protected boolean onDoubleClick(MouseEvent e) {
        close(OK_EXIT_CODE);
        return true;
      }
    }.installOn(myList);

    myList.setCellRenderer(new MyListCellRenderer());
    myList.addKeyListener(
        new KeyAdapter() {
          @Override
          public void keyPressed(KeyEvent e) {
            if (e.getKeyCode() == KeyEvent.VK_DELETE) {
              int newSelectionIndex = -1;
              for (Object o : myList.getSelectedValues()) {
                int i = ((Item) o).index;
                removeContentAt(myAllContents.get(i));
                if (newSelectionIndex < 0) {
                  newSelectionIndex = i;
                }
              }

              rebuildListContent();
              if (myAllContents.isEmpty()) {
                close(CANCEL_EXIT_CODE);
                return;
              }
              newSelectionIndex = Math.min(newSelectionIndex, myAllContents.size() - 1);
              myList.setSelectedIndex(newSelectionIndex);
            } else if (e.getKeyCode() == KeyEvent.VK_ENTER) {
              doOKAction();
            } else {
              final char aChar = e.getKeyChar();
              if (aChar >= '0' && aChar <= '9') {
                int idx = aChar == '0' ? 9 : aChar - '1';
                if (idx < myAllContents.size()) {
                  myList.setSelectedIndex(idx);
                  e.consume();
                  doOKAction();
                }
              }
            }
          }
        });

    mySplitter.setFirstComponent(
        ListWithFilter.wrap(
            myList,
            ScrollPaneFactory.createScrollPane(myList),
            new Function<Object, String>() {
              @Override
              public String fun(Object o) {
                return ((Item) o).longText;
              }
            }));
    mySplitter.setSecondComponent(new JPanel());
    rebuildListContent();

    ScrollingUtil.installActions(myList);
    ScrollingUtil.ensureSelectionExists(myList);
    updateViewerForSelection();
    myList.addListSelectionListener(
        new ListSelectionListener() {
          @Override
          public void valueChanged(ListSelectionEvent e) {
            myUpdateAlarm.cancelAllRequests();
            myUpdateAlarm.addRequest(
                new Runnable() {
                  @Override
                  public void run() {
                    updateViewerForSelection();
                  }
                },
                100);
          }
        });

    mySplitter.setPreferredSize(JBUI.size(500, 500));

    SplitterProportionsData d = new SplitterProportionsDataImpl();
    d.externalizeToDimensionService(getClass().getName());
    d.restoreSplitterProportions(mySplitter);

    return mySplitter;
  }
  protected void reInitWholePanelIfNeeded() {
    if (!myToReInitWholePanel) return;

    myWholePanel =
        new JPanel(new BorderLayout()) {
          public void addNotify() {
            super.addNotify();
            MasterDetailsComponent.this.addNotify();

            TreeModel m = myTree.getModel();
            if (m instanceof DefaultTreeModel) {
              DefaultTreeModel model = (DefaultTreeModel) m;
              for (int eachRow = 0; eachRow < myTree.getRowCount(); eachRow++) {
                TreePath eachPath = myTree.getPathForRow(eachRow);
                Object component = eachPath.getLastPathComponent();
                if (component instanceof TreeNode) {
                  model.nodeChanged((TreeNode) component);
                }
              }
            }
          }
        };
    mySplitter.setHonorComponentsMinimumSize(true);
    myWholePanel.add(mySplitter, BorderLayout.CENTER);

    JPanel left =
        new JPanel(new BorderLayout()) {
          public Dimension getMinimumSize() {
            final Dimension original = super.getMinimumSize();
            return new Dimension(Math.max(original.width, 100), original.height);
          }
        };

    if (isNewProjectSettings()) {
      ToolbarDecorator decorator = ToolbarDecorator.createDecorator(myTree);
      DefaultActionGroup group = createToolbarActionGroup();
      if (group != null) {
        decorator.setActionGroup(group);
      }
      // left.add(myNorthPanel, BorderLayout.NORTH);
      myMaster =
          decorator.setAsUsualTopToolbar().setPanelBorder(JBUI.Borders.empty()).createPanel();
      myNorthPanel.setVisible(false);
    } else {
      left.add(myNorthPanel, BorderLayout.NORTH);
      myMaster = ScrollPaneFactory.createScrollPane(myTree);
    }
    left.add(myMaster, BorderLayout.CENTER);
    mySplitter.setFirstComponent(left);

    final JPanel right = new JPanel(new BorderLayout());
    right.add(myDetails.getComponent(), BorderLayout.CENTER);
    if (!isNewProjectSettings()) {
      myWholePanel.setBorder(BorderFactory.createEmptyBorder(10, 10, 10, 10));
    }

    mySplitter.setSecondComponent(right);

    GuiUtils.replaceJSplitPaneWithIDEASplitter(myWholePanel);

    myToReInitWholePanel = false;
  }