Dual JList Layout

Question

I am trying to create a JPanel that has a JList on the left, one on the right and a tool bar in the middle. (JLists are in a JScrollPane) It is for selecting items and moving them between the two lists. That part works fine but I cannot get the layout to work out. I can get it to look nice in one container, but it will not re-size correctly. What I want is with a horizontal re-size both lists expand equally and the tool bar stays the same size, and vertical re-size the lists grow and the tool bar does not change. I have tried border, flow, box, group layouts and each one has some kind of issue. I need the lists to expand and re-size properly within the panel, and the tool bar to stay the same and in the center. So far group worked out the best, but the left list box was the only one that would re-size. After the lists where created, they will not re-size or expand with the border layout. Any suggestions and is there a way to specify what components will re-size and in what direction, and what ones will stay at a static size. I am using Jigloo to help with the group layouts, but I did the others by hand.
try {
               BorderLayout thisLayout = new BorderLayout();
               this.setLayout(thisLayout);
               this.setEnabled(false);
                    JPanel inPanel = new JPanel();
                    includeModel = new DefaultListModel();
                    include = new JList();
                    include.setModel(includeModel);
                    include.setCellRenderer(new CListCellRenderer());
                    inPanel.setBorder(BorderFactory.createTitledBorder(BorderFactory.createEtchedBorder(BevelBorder.LOWERED),
                              "Selected", TitledBorder.LEADING, TitledBorder.DEFAULT_POSITION));
                    inPanel.add(new JScrollPane(include));
                    JPanel avaPanel = new JPanel();
                    avalibleModel = new DefaultListModel();
                    avalible = new JList();
                    avalible.setModel(avalibleModel);
                    avalible.setCellRenderer(new CListCellRenderer());
                    avaPanel.setBorder(BorderFactory.createTitledBorder(BorderFactory.createEtchedBorder(BevelBorder.LOWERED),
                              "Avalible", TitledBorder.LEADING, TitledBorder.DEFAULT_POSITION));
                    avaPanel.add(new JScrollPane(avalible));
                    tools = new JToolBar();
                    tools.setOrientation(SwingConstants.VERTICAL);
                    tools.setFloatable(false);
                    this.add(inPanel, BorderLayout.LINE_START);
                    this.add(tools, BorderLayout.CENTER);
                    this.add(avaPanel, BorderLayout.LINE_END);
                         add = new JButton();
                         tools.add(add);
                         add.setIcon(new ImageIcon(getClass().getClassLoader().getResource("Support/Back24.gif")));
                         add.setActionCommand("add");
                         add.setToolTipText("Add Item(s)");
                         add.addActionListener(this);
                         del = new JButton();
                         tools.add(del);
                         del.setIcon(new ImageIcon(getClass().getClassLoader().getResource("Support/Forward24.gif")));
                         del.setActionCommand("del");
                         del.setToolTipText("Remove Item(s)");
                         del.addActionListener(this);
                         up = new JButton();
                         tools.add(up);
                         up.setIcon(new ImageIcon(getClass().getClassLoader().getResource("Support/Up24.gif")));
                         up.setActionCommand("up");
                         up.setToolTipText("Shift Item Up");
                         up.addActionListener(this);
                         down = new JButton();
                         tools.add(down);
                         down.setIcon(new ImageIcon(getClass().getClassLoader().getResource("Support/Down24.gif")));
                         down.setActionCommand("down");
                         down.setToolTipText("Shift Item Down");
                         down.addActionListener(this);
          } catch (Exception e) {
               e.printStackTrace();
          }

Answer 1

kb9mfd wrote:
I think I answered my own question, I did not try gridbaglayout. It looks like that is the one I need to use.Here's one way, using GridBagLayout. Keep in mind:
1) This is only one of many different ways to do this. Nested panels with varying LayoutManagers, which is a common technique, could also be implemented
2) This code is for illustrative purposes only. Those who use GBL frequently (like myself) usually have a helper class or two to make the code easier to read and manage. As a result, the sample code here wouldn't be nearly as long.
3) You described desired behaviors for stretching horizontally and vertically. You didn't mention shrinking. Regardless of LM used, I typically wrap my content panel in a JScrollPane (not shown here) to prevent unwanted results due to shrinkage ("I WAS IN THE POOL! I WAS IN THE POOL!!!").
import java.awt.*;
import javax.swing.*;
public class Demo implements Runnable {
  public static void main(String[] args) {
    SwingUtilities.invokeLater(new Demo());
  public void run() {
    String[] items = new String[] { "apple", "banana", "carrot", "date" };
    JPanel swapPanel = createSwapPanel(items);
    JFrame f = new JFrame();
    f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
    f.add(swapPanel, BorderLayout.CENTER);
    f.pack();
    f.setLocationRelativeTo(null);
    f.setVisible(true);
  private JPanel createSwapPanel(Object[] items) {
    JList availableList = new JList(items);
    availableList.setPrototypeCellValue("XXXXXXXXXX");
    availableList.setVisibleRowCount(6);
    JScrollPane availableScroll = new JScrollPane(availableList);
    availableScroll.setHorizontalScrollBarPolicy(
        JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
    availableScroll.setVerticalScrollBarPolicy(
        JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
    JList selectedList = new JList();
    selectedList.setPrototypeCellValue("XXXXXXXXXX");
    selectedList.setVisibleRowCount(6);
    JScrollPane selectedScroll = new JScrollPane(selectedList);
    selectedScroll.setHorizontalScrollBarPolicy(
        JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
    selectedScroll.setVerticalScrollBarPolicy(
        JScrollPane.VERTICAL_SCROLLBAR_ALWAYS);
    JButton addButton = new JButton(">");
    JButton removeButton = new JButton("<");
    JPanel p = new JPanel(new GridBagLayout());
    GridBagConstraints gbc = new GridBagConstraints();
    gbc.gridx = 0;
    gbc.gridy = 0;
    gbc.weightx = 0.5;
    gbc.weighty = 1.0;
    gbc.anchor = GridBagConstraints.NORTHWEST;
    gbc.fill = GridBagConstraints.BOTH;
    gbc.gridheight = 4;
    p.add(availableScroll, gbc);
    gbc.gridx = 1;
    gbc.gridy = 0;
    gbc.weightx = 0.0;
    gbc.weighty = 0.5;
    gbc.anchor = GridBagConstraints.CENTER;
    gbc.fill = GridBagConstraints.VERTICAL;
    gbc.gridheight = 1;
    p.add(Box.createVerticalGlue(), gbc);
    gbc.gridx = 1;
    gbc.gridy = 1;
    gbc.weightx = 0.0;
    gbc.weighty = 0.0;
    gbc.anchor = GridBagConstraints.CENTER;
    gbc.fill = GridBagConstraints.NONE;
    gbc.gridheight = 1;
    p.add(addButton, gbc);
    gbc.gridx = 1;
    gbc.gridy = 2;
    gbc.weightx = 0.0;
    gbc.weighty = 0.0;
    gbc.anchor = GridBagConstraints.CENTER;
    gbc.fill = GridBagConstraints.NONE;
    gbc.gridheight = 1;
    p.add(removeButton, gbc);
    gbc.gridx = 1;
    gbc.gridy = 3;
    gbc.weightx = 0.0;
    gbc.weighty = 0.5;
    gbc.anchor = GridBagConstraints.CENTER;
    gbc.fill = GridBagConstraints.VERTICAL;
    gbc.gridheight = 1;
    p.add(Box.createVerticalGlue(), gbc);
    gbc.gridx = 2;
    gbc.gridy = 0;
    gbc.weightx = 0.5;
    gbc.weighty = 1.0;
    gbc.anchor = GridBagConstraints.NORTHWEST;
    gbc.fill = GridBagConstraints.BOTH;
    gbc.gridheight = 4;
    p.add(selectedScroll, gbc);
    return p;
}