I'd like to be able to display a mutable list (using Swing) such that the first item is at the bottom in a fixed position, and subsequent items appear above it. Just the way a stack of stuff would appear in reality. The behavior is that of a FIFO queue (add to the top, remove from the bottom).
I can imagine a solution involving "padding" the list and then sorting it in reverse, or something like that, but I wondered if there might be a more direct way.
Example:
item[0]="Adam"
item[1]="Baker"
item[2]="Charlie"
should appear in 5-row list as:
+----------
|
|
| Charlie
| Baker
| Adam
+----------
If you don't want to create a custom model, then you can use the DefaultListModel. Then instead of using:
model.addElement( element );
you can use:
model.add(0, element);
and the elements will be displayed in the order you wish.
The following code also show how you might make the list look bigger than it really is:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;
public class ListBottom2 extends JFrame
{
JList list;
JTextField textField;
public ListBottom2()
{
DefaultListModel model = new DefaultListModel();
model.add(0, "Adam");
model.add(0, "Baker");
model.add(0, "Charlie");
list = new JList(model);
list.setVisibleRowCount(5);
JPanel box = new JPanel( new BorderLayout() );
box.setBackground( list.getBackground() );
box.add(list, BorderLayout.SOUTH);
JScrollPane scrollPane = new JScrollPane( box );
scrollPane.setPreferredSize(new Dimension(200, 95));
add( scrollPane );
textField = new JTextField("Use Enter to Add");
getContentPane().add(textField, BorderLayout.NORTH );
textField.addActionListener( new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
JTextField textField = (JTextField)e.getSource();
DefaultListModel model = (DefaultListModel)list.getModel();
// model.addElement( textField.getText() );
model.add(0, textField.getText());
int size = model.getSize() - 1;
list.scrollRectToVisible( list.getCellBounds(size, size) );
textField.setText("");
}
});
}
public static void main(String[] args)
{
ListBottom2 frame = new ListBottom2();
frame.setDefaultCloseOperation( EXIT_ON_CLOSE );
frame.pack();
frame.setLocationRelativeTo( null );
frame.setVisible( true );
}
}