日期:2014-05-20 浏览次数:21155 次
/**
@version 1.02 2004-08-21
@author Cay Horstmann
*/
package ultrapower;
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.tree.*;
/**
This program demonstrates tree editing.
*/
public class TreeEditTest
{
public static void main(String[] args)
{
JFrame frame = new TreeEditFrame();
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
}
}
/**
A frame with a tree and buttons to edit the tree.
*/
class TreeEditFrame extends JFrame
{
Container c=this.getContentPane();
public TreeEditFrame()
{
setTitle("TreeEditTest");
setSize(DEFAULT_WIDTH, DEFAULT_HEIGHT);
// construct tree
TreeNode root = makeSampleTree();
model = new DefaultTreeModel(root);
tree = new JTree(model);
tree.setEditable(true);
// add scroll pane with tree
JScrollPane scrollPane = new JScrollPane(tree);
c.add(scrollPane, BorderLayout.CENTER);
makeButtons();
}
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("San Diego");
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;
}
/**
Makes the buttons to add a sibling, add a child, and
delete a node.
*/
public void makeButtons()
{
JPanel panel = new JPanel();
JButton addSiblingButton = new JButton("Add Sibling");
addSiblingButton.addActionListener(new
ActionListener()
{
public void actionPerformed(ActionEvent event)
{
DefaultMutableTreeNode selectedNode
= (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
if (selectedNode == null) return;
DefaultMutableTreeNode parent
= (DefaultMutableTreeNode) selectedNode.getParent();
if (parent == null) return;
DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("New");
int selectedIndex = parent.getIndex(selectedNode);
model.insertNodeInto(newNode, parent, selectedIndex + 1);
// now display new node
TreeNode[] nodes = model.getPathToRoot(newNode);
TreePath path = new TreePath(nodes);
tree.scrollPathToVisible(path);
}
});
panel.add(addSiblingButton);
JButton addChildButton = new JButton("Add Child");
addChildButton.addActionListener(new
ActionListener()
{
public void actionPerformed(ActionEvent event)
{
DefaultMutableTreeNode selectedNode = (DefaultMutableTreeNode)
tree.getLastSelectedPathComponent();
if (selectedNode == null) return;
DefaultMutableTreeNode newNode = new DefaultMutableTreeNode("New");
model.insertNodeInto(newNode, selectedNode, selectedNode.getChildCount());
// now display new node
TreeNode[] nodes = model.getPathToRoot(newNode);
TreePath path = new TreePath(nodes);
tree.scrollPathToVisible(path);
}
});
panel.add(addChildButton);
JButton deleteButton = new JButton("Delete");
deleteButton.addActionListener(new
ActionListener()
{
public void actionPerformed(ActionEvent event)
{
DefaultMutableTreeNode selectedNode
= (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
if (selectedNode != null && selectedNode.getParent() != null)
model.removeNodeFromParent(selectedNode);
}
});
panel.add(deleteButton);
c.add(panel, BorderLayout.SOUTH);
}
private DefaultTreeModel model;
private JTree tree;
private static final int DEFAULT_WIDTH = 400;
private static final int DEFAULT_HEIGHT = 200;
}