树形菜单及其事件处理(java实现)

1、树形菜单及其事件儿处理（java实现）效果图如下：import java.awt.BorderLayout;import java.awt.EventQueue;import javax.swing.JFrame;import javax.swing.JPanel;import javax.swing.JScrollPane;import javax.swing.JSplitPane;import javax.swing.JTextArea;import javax.swing.JTree;import javax.swing.UIManager;import javax.swing.even

2、t.TreeSelectionEvent;import javax.swing.event.TreeSelectionListener;import javax.swing.tree.DefaultMutableTreeNode;import javax.swing.tree.DefaultTreeModel;import javax.swing.tree.TreePath;/* * 树形菜单及其事件处理 * * author xlfdzhf */SuppressWarnings("serial")public class TreeEventFrame extends JF

3、rame private JSplitPane splitPane;private JPanel leftPanel;private JPanel rightPanel;private JTree tree;private JTextArea textArea;TreeEventFrame()setSize( 500, 300 );setLayout( new BorderLayout();splitPane = new JSplitPane( JSplitPane.HORIZONTAL_SPLIT ); /1.左侧DefaultMutableTreeNode rootNode = new D

4、efaultMutableTreeNode("学科");DefaultMutableTreeNode level_1Node = new DefaultMutableTreeNode("数学");DefaultMutableTreeNode level_2Node = new DefaultMutableTreeNode("物理");rootNode.add( level_1Node );rootNode.add( level_2Node ); DefaultMutableTreeNode level_11Node = new Def

5、aultMutableTreeNode("小学数学");DefaultMutableTreeNode level_12Node = new DefaultMutableTreeNode("初中数学");DefaultMutableTreeNode level_13Node = new DefaultMutableTreeNode("高中数学");level_1Node.add(level_11Node);level_1Node.add(level_12Node);level_1Node.add(level_13Node); Defau

6、ltMutableTreeNode level_21Node = new DefaultMutableTreeNode("初中物理");DefaultMutableTreeNode level_22Node = new DefaultMutableTreeNode("高中物理");DefaultMutableTreeNode level_23Node = new DefaultMutableTreeNode("大学物理");level_2Node.add(level_21Node);level_2Node.add(level_22No

7、de);level_2Node.add(level_23Node); /面板设置leftPanel = new JPanel();leftPanel.setLayout( new BorderLayout();final JScrollPane leftScrollPane = new JScrollPane();DefaultTreeModel treeModel = new DefaultTreeModel( rootNode );tree = new JTree( treeModel );leftScrollPane.setViewportView( tree );leftPanel.a

8、dd( leftScrollPane , BorderLayout.CENTER ); splitPane.setDividerLocation( 120 );splitPane.setLeftComponent( leftPanel );getContentPane().add( splitPane , BorderLayout.CENTER ); /2.右侧final JScrollPane rightScrollPane = new JScrollPane();rightPanel = new JPanel();rightPanel.setLayout( new BorderLayout

9、();textArea = new JTextArea();rightPanel.add( textArea, BorderLayout.CENTER );rightScrollPane.setViewportView( rightPanel );splitPane.setRightComponent( rightScrollPane ); /3.树的事件处理tree.addTreeSelectionListener( new TreeSelectionListener()Overridepublic void valueChanged(TreeSelectionEvent arg0) /如果

10、不被选，则不执行，反之，执行if ( !tree.isSelectionEmpty()/获得所选节点的路径名TreePath selectPaths = tree.getSelectionPaths(); for ( int i = 0; i < selectPaths.length; i + )/System.out.println( selectPaths i );/以Object数组的形式返回该路径中的所有节点的对象Object paths = selectPaths i .getPath();for ( int j = 0; j < paths.length; j + )/

11、System.out.print( paths j + " -> " );DefaultMutableTreeNode node = (DefaultMutableTreeNode) paths j ;textArea.append( node.getUserObject() + ( j = paths.length -1 ) ? "":" -> ") );/( j = paths.length -1 ) ? "":" -> ")表示的是不在最后一个节点加入 “->”符号textArea.append("n");/System.out.println(););public static void main(String args) EventQueue.invokeLater( new Runnable()Overridepublic void run() try UIManager.setLookAndFeel(UIMana