求教Jtree的使用方法

Question

求教Jtree的使用方法 (添加 删除 修改),
 最好有完整的例子,谢了.

Answer 1

%JAVA_HOME%\demo\jfc\SwingSet2,基本包括swing所有的组件

Answer 2

import javax.swing.*;import javax.swing.tree.*;import java.awt.event.*;public class myTree extends JFrame{        JTree tree=null;        DefaultTreeModel model=null;        DefaultMutableTreeNode root=new DefaultMutableTreeNode("Root");        public myTree()        {                tree=new JTree(root);                model=(DefaultTreeModel)tree.getModel();                for(int i=0;i<10;i++)                {                        DefaultMutableTreeNode subNode=new DefaultMutableTreeNode("Node"+new Integer(i),true);                        root.add(subNode);                }                tree.addMouseListener(new java.awt.event.MouseAdapter()                 {            public void mousePressed(MouseEvent e) {                tree1_mousePressed(e);            }        });                this.getContentPane().add(tree);                this.setSize(100,300);                this.setVisible(true);                this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);        }                void tree_mousePressed(MouseEvent e)                 {                        TreePath path = tree.getPathForLocation(e.getX(),e.getY());                        tree.setSelectionPath(path);         }        public static void main(String[] args)        {                new myTree();        }}

Answer 3

/**
 *Swing中，树由扩展JComponent的JTree类来实现的。
 *使用JTree的最简单和最常用的方法是创建类型为DefaultMutableTreeNode的对象，以作为树的节点
 *没有子节电的的节点显示为叶
 */
 /**
  *DefaultMutableTreeNode root=new DefaultMutableTreeNode("根");
  *DefaultMutableTreeNode child1=new DefaultMutableTreeNode("子树1");
  *DefaultMutableTreeNode child2=new DefaultMutableTreeNode("子树2");
  *root.add(child1);
  *root.add(child2);
  *JTree tree=new JTree(root);
  *getContentPane().add(new JScrollPane(tree));
  */
 import javax.swing.*;
 import java.awt.*;
 import java.awt.event.*;
 import javax.swing.tree.*;
 //选择一个字符串数组，使第一个元素成为节点，其余的元素成为叶
 class Branch
 {
  DefaultMutableTreeNode r;
  Branch(String data[])
  {
  r=new DefaultMutableTreeNode(data[0]);
  for(int i=1;i<data.length;i++)
  r.add(new DefaultMutableTreeNode(data[i]));
  }
  public DefaultMutableTreeNode node()
  {
  return r;
  }
 }
 
 public class JTreeDemo extends JFrame
 {
  String[][]data={{"颜色","红色","蓝色","绿色"},
  {"风味","酸","甜","温和"},
  {"长度","短","中","长"},
  {"音量","高","中","低"},
  {"温度","高","中","低"},
  {"强度","高","中","低"}
  };
  static int i=0;
  DefaultMutableTreeNode root,child,chosen;
 
  JTree tree;
  DefaultTreeModel model;
 
  JTreeDemo()
  {
  Container cp=getContentPane();
  //创建树结构
  root=new DefaultMutableTreeNode("根");
  tree=new JTree(root);
  //添加它并使它完成滚动的操作
  cp.add(new JScrollPane(tree),BorderLayout.CENTER);
  //捕获树的模型
  model=(DefaultTreeModel)tree.getModel();
 
  JButton test=new JButton("添加");
  test.addActionListener(new ActionListener()
  {
 
  public void actionPerformed(ActionEvent e)
  {
  //构造Branch,并返回DefaultMutableTreeNode
  if (i<data.length)
  child=new Branch(data[i++]).node();
 
  //最后点击的是什么,获得最后点击的节点
  chosen=(DefaultMutableTreeNode)tree.getLastSelectedPathComponent();
  if(chosen==null)
  chosen=root;
 
  //将新节点放置在当前节点上,在chosen上添加子节点child
  model.insertNodeInto(child,chosen,0);
 
  }
  });
  //修改按钮的颜色
  test.setBackground(Color.blue);
test.setForeground(Color.white);
JPanel p=new JPanel();
p.add(test);
cp.add(p,BorderLayout.SOUTH); 
  }
  public static void main(String args[])
  {
JTreeDemo jj=new JTreeDemo();
jj.pack();
jj.show(); 
  }
 }

Answer 4

谢谢 chao_bsc_002(潮儿) 
但是关于节点的删除及修改部分的代码呢.

Answer 5

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;
}其中包含了添加兄弟和子节点，删除节点，双击该节点就能修改。Java核心技术 卷II中的例子，有详细的解释，tree.setEditable(true)这个方法就是使树可修改，model.removeNodeFromParent(selectedNode)是删除的部分。