要扩展 Walter +1 的建议，请从 JButton addButton 调用 Runnable#Thread
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.tree.*;
public class DynamicTreeDemo extends JPanel implements ActionListener {
private static final long serialVersionUID = 1L;
private int newNodeSuffix = 1;
private static String ADD_COMMAND = "add";
private static String REMOVE_COMMAND = "remove";
private static String CLEAR_COMMAND = "clear";
private DynamicTree treePanel;
public DynamicTreeDemo() {
super(new BorderLayout()); // Create the components.
treePanel = new DynamicTree();
populateTree(treePanel);
JButton addButton = new JButton("Add");
addButton.setActionCommand(ADD_COMMAND);
addButton.addActionListener(this);
JButton removeButton = new JButton("Remove");
removeButton.setActionCommand(REMOVE_COMMAND);
removeButton.addActionListener(this);
JButton clearButton = new JButton("Clear");
clearButton.setActionCommand(CLEAR_COMMAND);
clearButton.addActionListener(this); // Lay everything out.
treePanel.setPreferredSize(new Dimension(300, 150));
add(treePanel, BorderLayout.CENTER);
JPanel panel = new JPanel(new GridLayout(0, 3));
panel.add(addButton);
panel.add(removeButton);
panel.add(clearButton);
add(panel, BorderLayout.SOUTH);
}
public void populateTree(DynamicTree treePanel) {
String p1Name = "Parent 1";
String p2Name = "Parent 2";
String c1Name = "Child 1";
String c2Name = "Child 2";
DefaultMutableTreeNode p1, p2;
p1 = treePanel.addObject(null, p1Name);
p2 = treePanel.addObject(null, p2Name);
treePanel.addObject(p1, c1Name);
treePanel.addObject(p1, c2Name);
treePanel.addObject(p2, c1Name);
treePanel.addObject(p2, c2Name);
}
@Override
public void actionPerformed(ActionEvent e) {
String command = e.getActionCommand();
if (ADD_COMMAND.equals(command)) { // Add button clicked
treePanel.addObject("New Node " + newNodeSuffix++);
} else if (REMOVE_COMMAND.equals(command)) { // Remove button clicked
treePanel.removeCurrentNode();
} else if (CLEAR_COMMAND.equals(command)) { // Clear button clicked.
treePanel.clear();
}
}
private static void createAndShowGUI() { // Create and set up the window.
JFrame frame = new JFrame("DynamicTreeDemo");
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); // Create and set up the content pane.
DynamicTreeDemo newContentPane = new DynamicTreeDemo();
newContentPane.setOpaque(true); // content panes must be opaque
frame.setContentPane(newContentPane); // Display the window.
frame.pack();
frame.setVisible(true);
}
public static void main(String[] args) {
javax.swing.SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
createAndShowGUI();
}
});
}
}
class DynamicTree extends JPanel {
private static final long serialVersionUID = 1L;
private DefaultMutableTreeNode rootNode;
private DefaultTreeModel treeModel;
private JTree tree;
private Toolkit toolkit = Toolkit.getDefaultToolkit();
public DynamicTree() {
super(new GridLayout(1, 0));
rootNode = new DefaultMutableTreeNode("Root Node");
treeModel = new DefaultTreeModel(rootNode);
treeModel.addTreeModelListener(new MyTreeModelListener());
tree = new JTree(treeModel);
tree.setEditable(true);
tree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);
tree.setShowsRootHandles(true);
JScrollPane scrollPane = new JScrollPane(tree);
add(scrollPane);
}
public void clear() {
rootNode.removeAllChildren();
treeModel.reload();
}
public void removeCurrentNode() {
TreePath currentSelection = tree.getSelectionPath();
if (currentSelection != null) {
DefaultMutableTreeNode currentNode = (DefaultMutableTreeNode) (currentSelection.getLastPathComponent());
MutableTreeNode parent = (MutableTreeNode) (currentNode.getParent());
if (parent != null) {
treeModel.removeNodeFromParent(currentNode);
return;
}
} // Either there was no selection, or the root was selected.
toolkit.beep();
}
public DefaultMutableTreeNode addObject(Object child) {
DefaultMutableTreeNode parentNode = null;
TreePath parentPath = tree.getSelectionPath();
if (parentPath == null) {
parentNode = rootNode;
} else {
parentNode = (DefaultMutableTreeNode) (parentPath.getLastPathComponent());
}
return addObject(parentNode, child, true);
}
public DefaultMutableTreeNode addObject(DefaultMutableTreeNode parent, Object child) {
return addObject(parent, child, false);
}
public DefaultMutableTreeNode addObject(DefaultMutableTreeNode parent, Object child, boolean shouldBeVisible) {
DefaultMutableTreeNode childNode = new DefaultMutableTreeNode(child);
if (parent == null) {
parent = rootNode;
}
// It is key to invoke this on the TreeModel, and NOT DefaultMutableTreeNode
treeModel.insertNodeInto(childNode, parent, parent.getChildCount());
// Make sure the user can see the lovely new node.
if (shouldBeVisible) {
tree.scrollPathToVisible(new TreePath(childNode.getPath()));
}
return childNode;
}
class MyTreeModelListener implements TreeModelListener {
@Override
public void treeNodesChanged(TreeModelEvent e) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) (e.getTreePath().getLastPathComponent()); /*
* If the event lists children, then the changed node is the child of the
* node we've already gotten. Otherwise, the changed node and the
* specified node are the same.
*/ int index = e.getChildIndices()[0];
node = (DefaultMutableTreeNode) (node.getChildAt(index));
System.out.println("The user has finished editing the node.");
System.out.println("New value NodesChanged: " + node.getUserObject());
}
@Override
public void treeNodesInserted(TreeModelEvent e) {
DefaultMutableTreeNode node= (DefaultMutableTreeNode) (e.getTreePath().getLastPathComponent()); /*
* If the event lists children, then the changed node is the child of the
* node we've already gotten. Otherwise, the changed node and the
* specified node are the same.
*/ int index = e.getChildIndices()[0];
node = (DefaultMutableTreeNode) (node.getChildAt(index));
System.out.println("New value NodesInserted : " + node.getUserObject());
}
@Override
public void treeNodesRemoved(TreeModelEvent e) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) (e.getTreePath().getLastPathComponent()); /*
* If the event lists children, then the changed node is the child of the
* node we've already gotten. Otherwise, the changed node and the
* specified node are the same.
*/ int index = e.getChildIndices()[0];
node = (DefaultMutableTreeNode) (node.getChildAt(index));
System.out.println("New value NodesRemoved : " + node.getUserObject());
}
@Override
public void treeStructureChanged(TreeModelEvent e) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) (e.getTreePath().getLastPathComponent()); /*
* If the event lists children, then the changed node is the child of the
* node we've already gotten. Otherwise, the changed node and the
* specified node are the same.
*/ int index = e.getChildIndices()[0];
node = (DefaultMutableTreeNode) (node.getChildAt(index));
System.out.println("New value StructureChanged : " + node.getUserObject());
}
}
}