Node selection in jtree

[Preethi]

I have created a tree.Now,i want to get co-ordinates or the location of
all visible node when expanded...I tried to get the count of all nodes of only selected
node and also the co-ordinates...But i don't know how to take all the co-ordinates of
the visible nodes...Can anyone help me...

Code:

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */

package test;

 import java.awt.BorderLayout;
 import java.awt.Graphics;
 import java.awt.Rectangle;
 import java.util.Hashtable;
 import javax.swing.JApplet;
 import javax.swing.JPanel;
 import javax.swing.JScrollPane;
 import javax.swing.JTree;
 import javax.swing.UIManager;
 import javax.swing.event.TreeSelectionEvent;
 import javax.swing.event.TreeSelectionListener;
 import javax.swing.tree.DefaultMutableTreeNode;
 import javax.swing.tree.TreePath;
 /** * * @author 8563 */
 public class reg extends JApplet
 {
     private JTree tree;
     private Drawing drawing;
     int count;
     public DefaultMutableTreeNode createNodes()
     {
         DefaultMutableTreeNode rootnode = new DefaultMutableTreeNode("RESOURCE");
         DefaultMutableTreeNode resource1 = new DefaultMutableTreeNode("RESOURCE1");
         DefaultMutableTreeNode resource2 = new DefaultMutableTreeNode("RESOURCE2");
         DefaultMutableTreeNode resource3 = new DefaultMutableTreeNode("RESOURCE3");

         rootnode.add(resource1);
         rootnode.add(resource2);
         rootnode.add(resource3);
         resource1.add(new DefaultMutableTreeNode("task1"));
         resource1.add(new DefaultMutableTreeNode("task2"));
         resource1.add(new DefaultMutableTreeNode("task3"));
         resource2.add(new DefaultMutableTreeNode("task1"));
         resource2.add(new DefaultMutableTreeNode("task2"));
         resource2.add(new DefaultMutableTreeNode("task3"));
         resource3.add(new DefaultMutableTreeNode("task1"));
         resource3.add(new DefaultMutableTreeNode("task2"));
         resource3.add(new DefaultMutableTreeNode("task3"));
         return rootnode;
     }
     public void init()
     {
         try
         {
             UIManager.setLookAndFeel("com.sun.java.swing.plaf.windows.WindowsLookAndFeel");
         }
         catch (Exception evt)
         {
             evt.printStackTrace();
         }
         drawing = new Drawing();
         tree = new JTree(createNodes());
         tree.addTreeSelectionListener(drawing);
         JPanel p =  new JPanel();
         p.setLayout(new BorderLayout());
         p.add(tree, BorderLayout.WEST);
         p.add(drawing, BorderLayout.CENTER);
         getContentPane().add(new JScrollPane(p));
     }
     private  class Drawing extends JPanel implements TreeSelectionListener
     {
         JTree tree = new JTree();

         public String selectedParent = " ";
         private String selectedChildValue = "";
         private int selectedChildY = -1;
         private Hashtable nodeStates = new Hashtable();
         Object EXPANDED = new Object();
         boolean parentselected = false;
         TreePath path;
        @Override
        public void paintComponent (Graphics g)
        {
            super.paintComponent(g);
            int x = 30;
                       
            if(isExpanded(path)== false)
            {
                g.drawString(" paint",5,selectedChildY);
            }
            if (!selectedChildValue.equals("Resource1"))
            {
                g.drawString("Currently selected child: " + selectedChildValue + ".",70 , selectedChildY-25);
                repaint();
            }
           
        }
         public void valueChanged(TreeSelectionEvent e)
         {
             DefaultMutableTreeNode node = (DefaultMutableTreeNode)e.getPath().getLastPathComponent();

             boolean Path = e.isAddedPath();
             count= node.getChildCount();
             if(count > 0)
             {
                 parentselected = true;
             }
             System.out.println("node count  is : " + count);
             System.out.println("userobj : " + node.getUserObject());
             if(e.isAddedPath() == true)
             {
                // repaint();
             }
             if (Path == true)
             {
                 selectedChildValue = (String)node.getUserObject();
                 JTree tree = (JTree)e.getSource();
                 Rectangle bounds = tree.getPathBounds(e.getPath());
                 Rectangle rt = tree.getVisibleRect();
                 System.out.println("visible"+ rt.x);
                 selectedChildY = bounds.y + bounds.height;
             }
             else
             {
                 selectedChildValue = "";
                 selectedChildY = -1;
             }
             if(!node.isRoot())
             {
                 selectedParent  = (String)node.getUserObject();
                 JTree  tree = (JTree)e.getSource();
                 Rectangle bounds = tree.getPathBounds(e.getPath());
                 try
                 {
                    selectedChildY = bounds.y + bounds.x;
                 }
                 catch(NullPointerException ex){}

             }
            
         }
         public boolean isExpanded( TreePath path)
         {

             if (path== null)
                 return false;
             Object state = nodeStates.get(path);
             if ((state == null) || (state != EXPANDED))
                 return false;
             TreePath Path = path.getParentPath();
             if(Path!= null)
                 return isExpanded(Path);
             return true;
         }
     }
     
     public int isParent(TreePath path)
     {
         if(path.getParentPath().getPathCount()>0 && tree.getVisibleRowCount()>0)
         
            count = path.getPathCount();
            return count;
     }
 }

[Eranga]

Visible nodes means, expanded nodes in the tree?

[Preethi]

Yes...the expanded nodes

[Eranga]

I'm not clear one thing. As the visibility you get the coordinates of a rectangle. It's always 0, because it gives the result reference to the applet.

[hardwired]

Code:

//  <applet code="NodeLocTest" width="400" height="400"></applet>
import java.awt.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.tree.*;

public class NodeLocTest extends JApplet
                         implements TreeSelectionListener {
    Rectangle locater = new Rectangle();

    public void valueChanged(TreeSelectionEvent e) {
        TreePath path = e.getNewLeadSelectionPath();
        if(path == null)
            return;
        DefaultMutableTreeNode node =
            (DefaultMutableTreeNode)path.getLastPathComponent();
        JTree tree = (JTree)e.getSource();
        int row = tree.getRowForPath(path);
        Rectangle r = tree.getRowBounds(row);
        System.out.printf("row = %2d  r = [%2d, %3d, %d, %d]  node = %s%n",
                           row, r.x, r.y, r.width, r.height, node);
        locater.setBounds(r);
        tree.repaint();
    }

    public void init() {
        JTree tree = new JTree() {
            protected void paintComponent(Graphics g) {
                super.paintComponent(g);
                Graphics2D g2 = (Graphics2D)g;
                g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                                    RenderingHints.VALUE_ANTIALIAS_ON);
                g2.setPaint(Color.red);
                g2.draw(locater);
            }
        };
        int mode = TreeSelectionModel.SINGLE_TREE_SELECTION;
        tree.getSelectionModel().setSelectionMode(mode);
        tree.addTreeSelectionListener(this);
        tree.addTreeWillExpandListener(willCall);
        add(tree);
    }

    private TreeWillExpandListener willCall = new TreeWillExpandListener() {
        JTree tree;

        public void treeWillCollapse(TreeExpansionEvent e) {
            checkLocation(e);
        }

        public void treeWillExpand(TreeExpansionEvent e) {
            checkLocation(e);
        }

        private void checkLocation(TreeExpansionEvent e) {
            if(tree == null)
                tree = (JTree)e.getSource();
            int changeRow = tree.getRowForPath(e.getPath());
            int selectedRow = tree.getLeadSelectionRow();
            if(changeRow < selectedRow)
                locater.setSize(0,0);
        }
    };
}