JComboBox 下拉树问题

12年前
在JDK1.5下，点击下拉框可以正常的弹出树，但是当把JDK换成1.6的时候，就弹不出树形结构了
下面是我的源码：
public class MyComboBox extends JComboBox {
    private boolean _eventEnabled = true;
    private JPopupMenu _popup;
    private Component _popupComp;
    private Dimension _popupSize;
    private ComponentHandler _componentHandler;
    private MouseHandler _mouseHandler;
    private JList _popupList;
    private FocusHander _focusHandler;
    public MyComboBox() {
        setEditable(true);
        setAutoscrolls(true);
        Component re = getRenderer().getListCellRendererComponent(getPopupList(),
            null, -1, false, false);
        _componentHandler = new ComponentHandler();
        re.addComponentListener(_componentHandler);
        _mouseHandler = new MouseHandler();
        _focusHandler = new FocusHander();
         getEditor().getEditorComponent().addFocusListener(_focusHandler);
    }
    public void setPopupComponent(Component comp) {
        if (!comp.equals(_popupComp)) {
            if (_popupComp != null) {
                _popupComp.removeMouseListener(_mouseHandler);
            }
            _popupComp = comp;
            if (_popupComp != null) {
                _popupComp.addMouseListener(_mouseHandler);
            }
        }
        convertPopupDataToComboBox();
    }
    public void convertPopupDataToComboBox() {
        AbstractListModel amodel = (AbstractListModel) getModel();
        ListDataListener[] lListener = amodel.getListDataListeners();
        if (lListener != null) {
            for (int i = 0, length = lListener.length; i < length; i++) {
                amodel.removeListDataListener(lListener[i]);
            }
        }
        ActionListener[] aListener = getActionListeners();
        if (aListener != null) {
            for (int i = 0, length = aListener.length; i < length; i++) {
                removeActionListener(aListener[i]);
            }
        }
        ItemListener[] iListener = getItemListeners();
        if (iListener != null) {
            for (int i = 0, length = iListener.length; i < length; i++) {
                removeItemListener(iListener[i]);
            }
        }
        PopupMenuListener[] pListener = getPopupMenuListeners();
        if (pListener != null) {
            for (int i = 0, length = pListener.length; i < length; i++) {
                removePopupMenuListener(pListener[i]);
            }
        }
        removeAllItems();
        if (_popupComp instanceof JTree) {
            JTree tree = (JTree) _popupComp;
            //将树里面的数据添加到
            DefaultTreeModel model = (DefaultTreeModel) tree.getModel();
            DefaultMutableTreeNode node = (DefaultMutableTreeNode) model.getRoot();
            if (node != null) {
                addItem(node.getUserObject());
                while ((node = (DefaultMutableTreeNode) node.getNextNode()) != null) {
                    addItem(node.getUserObject());
                }
            }
        }
        setSelectedItem(null);
        if (lListener != null) {
            for (int i = lListener.length - 1; i >= 0; i--) {
                amodel.addListDataListener(lListener[i]);
            }
        }
        if (aListener != null) {
            for (int i = aListener.length - 1; i >= 0; i--) {
                addActionListener(aListener[i]);
            }
        }
        if (iListener != null) {
            for (int i = iListener.length - 1; i >= 0; i--) {
                addItemListener(iListener[i]);
            }
        }
        if (pListener != null) {
            for (int i = pListener.length - 1; i >= 0; i--) {
                addPopupMenuListener(pListener[i]);
            }
        }
    }
    public JList getPopupList() {
        if (_popupList == null) {
            Accessible a = getUI().getAccessibleChild(MyComboBox.this, 0);
            if (a instanceof javax.swing.plaf.basic.ComboPopup) {
                _popupList = ((javax.swing.plaf.basic.ComboPopup) a).getList();
            }
        }
        return _popupList;
    }
    private class ComponentHandler extends ComponentAdapter {
        public void componentMoved(ComponentEvent e) {
            initPopup(e);
        }
        public void componentResized(ComponentEvent e) {
            initPopup(e);
        }
        public void componentShown(ComponentEvent e) {
            initPopup(e);
        }
        private void initPopup(ComponentEvent e) {
            if (_popup != null && _popupComp != null
                && _popup.isAncestorOf(_popupComp)) {
                return;
            }
            Component comp = e.getComponent();
            while ((comp = comp.getParent()) != null) {
                if (comp instanceof JPopupMenu) {
                    break;
                }
            }
            if (!(comp instanceof JPopupMenu)) {
                return;
            }
            _popup = (JPopupMenu) comp;
            if (_popupComp != null) {
                _popup.removeAll();
                JScrollPane spn = new JScrollPane(_popupComp) {
                    public Insets getInsets() {
                        return new Insets(5, 5, 5, 5);
                    }
                };
                if (_popupSize != null) {
                    spn.setPreferredSize(_popupSize);
                }
                else {
                    Dimension size = _popupComp.getPreferredSize();
                    if (size.getHeight() < 180) {
                        Dimension screenSize = Toolkit.getDefaultToolkit().
                                               getScreenSize();
                        Point point = _popup.getLocationOnScreen();
                        if (point.y > screenSize.getHeight() / 2) {
                            spn.setPreferredSize(new Dimension(getWidth(),
                                screenSize.height - point.y - 50));
                        }
                        else {
                            spn.setPreferredSize(new Dimension(getWidth(),
                                screenSize.height / 2));
                        }
                    }
                    else {
                        spn.setPreferredSize(new Dimension(getWidth(),
                            size.height));
                    }
                }
                _popup.add(spn);
                _popup.revalidate();
                _popup.repaint();
            }
        }
    }
    private class MouseHandler extends MouseAdapter {
        public void mousePressed(MouseEvent e) {
            if (e.getClickCount() > 1) {
                if (_popupComp instanceof JTree
                    && ((JTree) _popupComp).getPathForLocation(e.getX(),
                    e.getY()) != null) {
                    TreePath path = ((JTree) _popupComp).getSelectionPath();
                    if (path == null) {
                        return;
                    }
                    TreeNode node = (TreeNode) path. getLastPathComponent();
                    if (node == null) {
                        return;
                    }
                    if (!node.isLeaf() &&
                        ((JTree) _popupComp).isCollapsed(path)) {
                        return;
                    }
                     Object object = ((JTree)_popupComp).getSelectionPath().getLastPathComponent();
                    if (object != null) {
                        setSelectedItem(object.toString());
                    }
                    _popup.setVisible(false);
                    requestFocus();
                }
            }
        }
    }
    private Component getEditorComponent() {
        return this.getEditor().getEditorComponent();
    }
    private JComboBox getComboBox() {
        return this;
    }
    private class FocusHander implements FocusListener {
        public void focusGained(FocusEvent e) {
            if (e.getSource() == getEditorComponent()) {
                return;
            }
            getComboBox().repaint();
            if (getComboBox().isEditable() && editor != null) {
                getEditorComponent().requestFocus();
            }
        }
        public void focusLost(FocusEvent e) {
            if (e.getSource() ==
                getComboBox().getEditor().getEditorComponent()) {
                ComboBoxEditor editor = getComboBox().getEditor();
                Object item = editor.getItem();

                if (!e.isTemporary() && item != null &&
                    !item.equals(getComboBox().getSelectedItem())) {
                    getComboBox().actionPerformed(new ActionEvent(editor, 0, "",
                            EventQueue.getMostRecentEventTime(), 0));
                }
            }
            if(e.getOppositeComponent() == _popupComp && null != _popup) {
                _popup.setVisible(true);
            }
            getComboBox().repaint();
        }
    }
}
调用类：
public class Frame1 extends JFrame {
    private MyComboBox _cmb = new MyComboBox();
    private JLabel Label1 = new JLabel();
    public Frame1() { try {
            jbInit();
            init();
        } catch (Exception ex) {
            ex.printStackTrace();
        }
    }

    private void jbInit() throws Exception {
        this.getContentPane().setLayout(null);
        _cmb.setBounds(new Rectangle(99, 31, 113, 30));
        this.getContentPane().add(_cmb);
        Label1.setText("树形测试：");
        Label1.setBounds(new Rectangle(21, 33, 71, 29));
        this.getContentPane().add(Label1);
        this.setSize(300,800);
    }

    private void init() {
        _cmb.removeAllItems();
        JTree supplierTree = new JTree(); ;
        _cmb.setPopupComponent(supplierTree);
        _cmb.convertPopupDataToComboBox();
    }
   
    public static void main(String[] args) {
        Frame1 frame = new Frame1();
        frame.setVisible(true);
    }
}
哪位高手帮我看看。