java树组件

package 树组件;import java.awt.Component;public class Example9_12 {public static void main(String args[]){TreeWin win=new TreeWin();win.setTitle("树组件");}}

package 树组件;import java.awt.*;import java.awt.event.*;import javax.swing.*;import javax.swing.event.*;import javax.swing.tree.*;public class TreeWin extends JFrame implements TreeSelectionListener,ActionListener{JTree tree;JTextArea showText;TreeWin(){setLayout(new FlowLayout());DefaultMutableTreeNode root=new DefaultMutableTreeNode("商品");DefaultMutableTreeNode nodeTV=new DefaultMutableTreeNode("电视机类");DefaultMutableTreeNode nodePhone=new DefaultMutableTreeNode("手机类");DefaultMutableTreeNode tv1=new DefaultMutableTreeNode(new Goods("长虹电视",5699));DefaultMutableTreeNode tv2=new DefaultMutableTreeNode(new Goods("海尔电视",7832));DefaultMutableTreeNode phone1=new DefaultMutableTreeNode(new Goods("诺基亚手机",7320));DefaultMutableTreeNode phone2=new DefaultMutableTreeNode(new Goods("小米手机",7882));DefaultMutableTreeNode phone3=new DefaultMutableTreeNode(new Goods("三星手机",7302));root.add(nodeTV);root.add(nodePhone);nodeTV.add(tv1);nodeTV.add(tv2);nodePhone.add(phone1);nodePhone.add(phone2);nodePhone.add(phone3);tree=new JTree(root);tree.addTreeSelectionListener(this);showText=new JTextArea();setLayout(new GridLayout(1,3));add(new JScrollPane(tree));add(new JScrollPane(showText));JButton button=new JButton("确定");add(button);button.addActionListener(this);setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);setVisible(true);setBounds(80,80,300,300);validate();}public void actionPerformed(ActionEvent e){int n=JOptionPane.showConfirmDialog(this, "确定要关闭吗？","确认对话框",JOptionPane.YES_NO_CANCEL_OPTION);if(n==JOptionPane.YES_OPTION){dispose();}}public void valueChanged(TreeSelectionEvent e){DefaultMutableTreeNode node=(DefaultMutableTreeNode)tree.getLastSelectedPathComponent();if(node.isLeaf()){Goods s=(Goods)node.getUserObject();showText.append(s.name+","+s.price+"元\n");}elseshowText.setText(null);}}

package 树组件;public class Goods {String name;double price;Goods(String n,double s){name=n;price=s;}public String toString(){return name;}}

这是运行结果：