Need Guru's help!!

[xiao li]

Hi Swing Gurus,
I need to show the labels with its mnemonic key in a scollPane. but it does not work(neither label nor mnemonic key is shown up).
here is my sample code:
import javax.swing.*;
import java.awt.*;
import java.util.*;
class MnemonicTest extends JDialog
{
JLabel label1 = new JLabel("A");
JLabel label2 = new JLabel("B");
JLabel label3 = new JLabel("C");
Vector vector = new Vector();
JList list;
JScrollPane scrollpane;

public MnemonicTest ()
{
label1.setDisplayedMnemonic('A');
label2.setDisplayedMnemonic('B');
label3.setDisplayedMnemonic('C');
vector.addElement(label1);
vector.addElement(label2);
vector.addElement(label3);
list = new JList(vector);
scrollpane= new JScrollPane(list);
setSize(400, 100);
getContentPane().setLayout(new BorderLayout());
getContentPane().add(BorderLayout.CENTER, scrollpane);
setVisible(true);
}
public static void main(String ag[])
{
MnemonicTest mt = new MnemonicTest ();
}
}
Thanks in advance!!

[Sayed Ibrahim Hashimi]

I'm not exactly sure on this but, my understanding of JScrollPane is that it was designed to scroll ONE Object, not many. If you want to Scroll something with 3 Components (in your case lables) then you should add those to a panel and have the JScrollPane scroll that.
Heres the fixed code:

import javax.swing.*;
import java.awt.*;
import java.util.*;
class MnemonicTest extends JDialog
{
    JLabel label1 = new JLabel("A");
    JLabel label2 = new JLabel("B");
    JLabel label3 = new JLabel("C");
    Vector vector = new Vector();
    JList list;
    JScrollPane scrollpane; 

    public MnemonicTest ()
    { 
        
        label1.setDisplayedMnemonic('A');
        label2.setDisplayedMnemonic('B');
        label3.setDisplayedMnemonic('C');
        
        vector.add(label1);
        vector.add(label2);
        vector.add(label3);
        
        list = new JList(vector);
            
        JPanel panel = new JPanel();
        panel.add(label1);
        panel.add(label2);  //add all the JLables to the panel
        panel.add(label3);
        //scrollpane= new JScrollPane(list);
        scrollpane = new JScrollPane(panel);    //have the JScrollPane scroll the panel
        
        setSize(400, 100);
        getContentPane().setLayout(new BorderLayout());
        getContentPane().add(BorderLayout.CENTER, scrollpane);
        //getContentPane().add(BorderLayout.CENTER, label1);
        setVisible(true); 
    }
    public static void main(String ag[])
    {
        MnemonicTest mt = new MnemonicTest ();
    }
}  

The reason why you don't want add the Lables to a JList is because a JList is designed to have text. So when you add Objects it will simply display the String representation of it. So when you added those labels all it did was call its toString() and that was what you were seeing.
Hope this helps
[ April 16, 2002: Message edited by: Ibrahim Hashimi ]

[Manfred Leonhardt]

Hi xiao,
You need to create your own cell renderer to do that. You can then tailor the list created label to match the one you are sending in. The code below shows a cell renderer to do what you want.

class MyCellRenderer extends JLabel implements ListCellRenderer 
{
  public Component getListCellRendererComponent( JList list,
       Object value,            // value to display
       int index,               // cell index
       boolean isSelected,      // is the cell selected
       boolean cellHasFocus)    // the list and the cell have the focus
  {
    JLabel label = (JLabel)value;
    String s = label.getText();
    setText( s );
    setEnabled( list.isEnabled() );
    setFont( list.getFont() );
    setDisplayedMnemonic( label.getDisplayedMnemonic() );
    return( this );
  }
}

To use it you just need to add a new line to your code, immediately after you create your JList:
list.setCellRenderer( new MyCellRenderer() );
Regards,
Manfred.