Re: problems with editable JList
On 2/17/2014 7:53 AM, blmblm@myrealbox.com wrote:
What I want:
After adding a new element, the new element is selected.
...
How I'm trying to accomplish this:
In my extension of JList, I attach a ListDataListener to the list
data model, and in the listener's methods that deal with addition and
removal events I use setSelectedIndex() or clearSelection() to change
I think your event listeners are tripping you up. They're probably
firing twice, or continuously until an error happens, after each time
you try to modify the list including modifications by the event listener
itself.
I made a simple program to modify a list, and it works fine. I didn't
use any event listeners. Try starting with this, see if you can use the
same template to get "Remove" working. "Add" seems to work fine.
/*
* To change this license header, choose License Headers in Project
Properties.
* To change this template file, choose Tools | Templates
* and open the template in the editor.
*/
package quicktest;
import java.awt.BorderLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import javax.swing.Box;
import javax.swing.DefaultListModel;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JList;
import javax.swing.SwingUtilities;
/**
*
* @author Brenden Towey
*/
public class JListTest
{
public static void main( String[] args )
{
SwingUtilities.invokeLater( new Runnable()
{
public void run()
{
JFrame frame = new JFrame();
final DefaultListModel listModel = new DefaultListModel();
Object[] test = { "One", "Two", "Three" };
for( Object li : test )
listModel.addElement( li );
final JList list = new JList( listModel );
frame.add( list );
Box vbox = Box.createVerticalBox();
JButton addButton = new JButton( "Add" );
vbox.add( addButton );
JButton removeButton = new JButton( "Remove" );
vbox.add( removeButton );
frame.add( vbox, BorderLayout.EAST );
addButton.addActionListener( new ActionListener()
{
int count = 0;
@Override
public void actionPerformed( ActionEvent e )
{
listModel.addElement( "Add "+ ++count );
list.setSelectedIndex( listModel.getSize()-1 );
}
} );
frame.pack();
frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );
frame.setSize( 350, 350 );
frame.setLocationRelativeTo( null );
frame.setVisible( true );
}
} );
}
}