Re: JTree Selection lost when JTree looses focus

From:
 Jean-Baptiste Nizet <jnizet@gmail.com>
Newsgroups:
comp.lang.java.programmer
Date:
Mon, 12 Nov 2007 15:55:05 -0000
Message-ID:
<1194882905.147188.123190@22g2000hsm.googlegroups.com>
On 12 nov, 09:43, jumpz <l33tsp3...@gmail.com> wrote:

Is there a way to prevent a JTree from loosing it's selection when it
looses focus? Say I have a few items selected in the JTree and then I
go to press a button, that normally causes the JTree to unselect
everything, how can I stop this?


I don't have this behaviour on my machine (Windows XP, Java 1.5.0_10).
When I run the following program, select some tree nodes and press the
button at the bottom, it prints out the selected paths as it should.
Maybe it's your code that has a problem, but you don't show us
anything.

JB.

package foo;

import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
import javax.swing.tree.TreeModel;
import javax.swing.tree.TreePath;

public class TreeTest extends JFrame {

  public TreeTest() {
    super("Tree test");
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    DefaultMutableTreeNode root = new DefaultMutableTreeNode("root");
    root.add(new DefaultMutableTreeNode("child1"));
    root.add(new DefaultMutableTreeNode("child2"));
    root.add(new DefaultMutableTreeNode("child3"));
    TreeModel treeModel = new DefaultTreeModel(root);
    final JTree tree = new JTree(treeModel);
    getContentPane().add(new JScrollPane(tree), BorderLayout.CENTER);
    JButton button = new JButton("Print selection");
    button.addActionListener(new ActionListener() {
      public void actionPerformed(ActionEvent e) {
        TreePath[] selectedPaths =
tree.getSelectionModel().getSelectionPaths();
        if (selectedPaths != null) {
          for (TreePath tp : selectedPaths) {
            System.out.println(tp);
          }
        }
      }
    });
    getContentPane().add(button, BorderLayout.SOUTH);
    pack();
  }

  public static void main(String[] args) {
    TreeTest t = new TreeTest();
    t.setVisible(true);
  }
}

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