celleditordemo.java

《java事件处理指南》一书的代码,好东西

import javax.swing.*;
import javax.swing.tree.*;
import javax.swing.event.*;
import java.awt.*;
import java.awt.event.*;

public class CellEditorDemo extends JFrame
{
   private JTree tree;
   private JTextField jtf;
   private DefaultTreeCellEditor editor;

   public CellEditorDemo() 
   {
/*  A Collection of DefaultMutableTreeNode objects are created that  */
/*  will form the components of a tree.                              */

      DefaultMutableTreeNode league = 
               new DefaultMutableTreeNode("Soccer League");

      DefaultMutableTreeNode north = 
                  new DefaultMutableTreeNode("North Division");
      DefaultMutableTreeNode south = 
                  new DefaultMutableTreeNode("South Divison");

      DefaultMutableTreeNode jets = 
                      new DefaultMutableTreeNode("Jets");
      DefaultMutableTreeNode raiders = 
                      new DefaultMutableTreeNode("Raiders");
      DefaultMutableTreeNode fins = 
                      new DefaultMutableTreeNode("Fins");
      DefaultMutableTreeNode shooters = 
                      new DefaultMutableTreeNode("Shooters");
      DefaultMutableTreeNode lions = 
                      new DefaultMutableTreeNode("Lions");
      DefaultMutableTreeNode tigers = 
                      new DefaultMutableTreeNode("Tigers");

/*  The node hierarchy is loaded into a DefaultTreeModel object.   */

      DefaultTreeModel model = new DefaultTreeModel(league);
      model.insertNodeInto(north, league, 0);
      model.insertNodeInto(south, league, 1);
      model.insertNodeInto(jets, north, 0);
      model.insertNodeInto(raiders, north, 1);
      model.insertNodeInto(fins, north, 2);
      model.insertNodeInto(shooters, south, 0);
      model.insertNodeInto(lions, south, 1);
      model.insertNodeInto(tigers, south, 2);

/*  A DefaultTreeCellEditor is created and registers a   */
/*  CellEditorListener.                                  */

      editor = new DefaultTreeCellEditor(tree, 
                                         new DefaultTreeCellRenderer());
      editor.addCellEditorListener(new CellEditorHandler());

/*  A JTree object is created using the previously created tree model.  */

      tree = new JTree(model);
      tree.setShowsRootHandles(true);
      tree.expandRow(1);
      tree.setEditable(true);
      tree.setCellEditor(editor);
      tree.setInvokesStopCellEditing(false);

      jtf = new JTextField(20);
      jtf.setEditable(false);

      getContentPane().add( new JScrollPane(tree), BorderLayout.CENTER );
      getContentPane().add( jtf, BorderLayout.SOUTH );

      setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      setBounds(100, 100, 400, 300);
      setVisible(true);
   }

/*  The CellEditorListener is implemented as an inner class.      */
/*  When the user exits the cell editor by pressing the return    */
/*  key or clicking on another node, a ChangeEvent is generated   */
/*  and sent to either the editingCanceled() or editingStopped()  */
/*  methods.  A textfield is updated to indicate which operation  */
/*  has occurred.                                                 */

   class CellEditorHandler implements CellEditorListener
   {
      public void editingCanceled(ChangeEvent event)
      {
         jtf.setText("editing canceled");
      }

      public void editingStopped(ChangeEvent event)
      {
         jtf.setText("editing stopped");
      }
   }

   public static void main(String args[]) 
   {
      CellEditorDemo demo = new CellEditorDemo();
   }
}