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Question on creating a custom DefaultListModel

I'd like to be able to display a 2D array within a JList.  The array will look like this:

private final String[][] selection =
     { {"value1","display string 1" }, {"value2","display string 2"} ... };

where the goal I'm trying to achieve is to view "the display strings" within the JList.

The first thing I did was to create this class that extends javax.swing.DefaultListModel:

public class ValueListModel extends DefaultListModel {
     private String[][] values;
     
     public ValueListModel(String[][] values) {
          this.values = values;
     }
      
     public Object getElementAt(int index) {
          return values[index][1];
     }
}

Next, I create a custom ListCellRenderer as:

public class ValueListCellRenderer extends JLabel implements ListCellRenderer {
     private String[][] values;
      
     public ValueListCellRenderer(String[][] values) {
          setOpaque(true);
          this.values = values;
     }

     public Component getListCellRendererComponent(JList list, Object value,
                  int index, boolean isSelected, boolean cellHasFocus) {
          setText(values[index][1]);
          setBackground(isSelected ? UIManager.getColor("List.selectionBackground")
                  : UIManager.getColor("List.background"));
          setForeground(isSelected ? UIManager.getColor("List.selectionForeground")
                  : UIManager.getColor("List.foreground"));
          return this;
     }
}

Finally in my GUI code, I instantiate instances of these classes and set the JList's model and cell renderer with the respective instances.  My problem is that the display strings are not being displayed.

Question: Will I have to override more of the methods of the DefaultListModel? If so, which ones?

Thanks in advance for any assistance.
0
mwalker
Asked:
mwalker
  • 2
1 Solution
 
CEHJCommented:
You need

public int getSize() { return values.length; }

in your list model
0
 
CEHJCommented:
8-)
0

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