/**
   * Adds a component to the middle layer of the desktop--that is, the layer for session node
   * editors. Note: The comp is a SessionEditor
   */
  public void addSessionEditor(SessionEditorIndirectRef editorRef) {
    SessionEditor editor = (SessionEditor) editorRef;

    JInternalFrame frame = new TetradInternalFrame(null);

    frame.getContentPane().add(editor);
    framesMap.put(editor, frame);
    editor.addPropertyChangeListener(this);

    // Set the "small" size of the frame so that it has sensible
    // bounds when the users unmazimizes it.
    Dimension fullSize = desktopPane.getSize();
    int smallSize = Math.min(fullSize.width - MARGIN, fullSize.height - MARGIN);
    Dimension size = new Dimension(smallSize, smallSize);
    setGoodBounds(frame, desktopPane, size);
    desktopPane.add(frame);

    // Set the frame to be maximized. This step must come after the frame
    // is added to the desktop. -Raul. 6/21/01
    try {
      frame.setMaximum(true);
    } catch (Exception e) {
      throw new RuntimeException("Problem setting frame to max: " + frame);
    }

    desktopPane.setLayer(frame, 0);
    frame.moveToFront();
    frame.setTitle(editor.getName());
    frame.setVisible(true);

    setMainTitle(editor.getName());
  }