treeedittest.java

sun公司开发的,java2核心技术,卷II:高级性能,包括一系列的高级java应用技术,如数据库德连接,高级swing,多线程,软件本地化等等,本文件中则包含该书中的所用实例,配合该书使用,使对ja

/**
 * @version 1.00 1999-07-17
 * @author Cay Horstmann
 */

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.tree.*;

public class TreeEditTest
{  public static void main(String[] args)
   {  JFrame frame = new TreeEditFrame();
      frame.show();
   }
}

class TreeEditFrame extends JFrame
   implements ActionListener
{  public TreeEditFrame()
   {  setTitle("TreeEditTest");
      setSize(300, 200);
      addWindowListener(new WindowAdapter()
         {  public void windowClosing(WindowEvent e)
            {  System.exit(0);
            }
         } );

      // construct tree

      TreeNode root = makeSampleTree();
      model = new DefaultTreeModel(root);
      tree = new JTree(model);
      tree.setEditable(true);

      // add scroll pane with tree to content pane

      Container contentPane = getContentPane();
      JScrollPane scrollPane = new JScrollPane(tree);
      contentPane.add(scrollPane, "Center");

      // make button panel

      JPanel panel = new JPanel();
      addSiblingButton = new JButton("Add Sibling");
      addSiblingButton.addActionListener(this);
      panel.add(addSiblingButton);
      addChildButton = new JButton("Add Child");
      addChildButton.addActionListener(this);
      panel.add(addChildButton);
      deleteButton = new JButton("Delete");
      deleteButton.addActionListener(this);
      panel.add(deleteButton);
      contentPane.add(panel, "South");
   }

   public TreeNode makeSampleTree()
   {  DefaultMutableTreeNode root
         = new DefaultMutableTreeNode("World");
      DefaultMutableTreeNode country
         = new DefaultMutableTreeNode("USA");
      root.add(country);
      DefaultMutableTreeNode state
         = new DefaultMutableTreeNode("California");
      country.add(state);
      DefaultMutableTreeNode city
         = new DefaultMutableTreeNode("San Jose");
      state.add(city);
      city = new DefaultMutableTreeNode("Cupertino");
      state.add(city);
      state = new DefaultMutableTreeNode("Michigan");
      country.add(state);
      city = new DefaultMutableTreeNode("Ann Arbor");
      state.add(city);
      country = new DefaultMutableTreeNode("Germany");
      root.add(country);
      state = new DefaultMutableTreeNode("Schleswig-Holstein");
      country.add(state);
      city = new DefaultMutableTreeNode("Kiel");
      state.add(city);
      return root;
   }

   public void actionPerformed(ActionEvent event)
   {  DefaultMutableTreeNode selectedNode
         = (DefaultMutableTreeNode)
            tree.getLastSelectedPathComponent();

      if (selectedNode == null) return;

      if (event.getSource().equals(deleteButton))
      {  if (selectedNode.getParent() != null)
            model.removeNodeFromParent(selectedNode);
         return;
      }

      // add new node as sibling or child

      DefaultMutableTreeNode newNode
         = new DefaultMutableTreeNode("New");

      if (event.getSource().equals(addSiblingButton))
      {  DefaultMutableTreeNode parent
            = (DefaultMutableTreeNode)selectedNode.getParent();

         if (parent != null)
         {  int selectedIndex = parent.getIndex(selectedNode);
            model.insertNodeInto(newNode, parent,
               selectedIndex + 1);
         }
      }
      else if (event.getSource().equals(addChildButton))
      {  model.insertNodeInto(newNode, selectedNode,
            selectedNode.getChildCount());
      }

      // now display new node

      TreeNode[] nodes = model.getPathToRoot(newNode);
      TreePath path = new TreePath(nodes);
      tree.scrollPathToVisible(path);
   }

   private DefaultTreeModel model;
   private JTree tree;
   private JButton addSiblingButton;
   private JButton addChildButton;
   private JButton deleteButton;
   private JButton editButton;
}