public interface

ListCellRenderer

javax.swing.ListCellRenderer
Known Indirect Subclasses

Class Overview

Identifies components that can be used as "rubber stamps" to paint the cells in a JList. For example, to use a JLabel as a ListCellRenderer, you would write something like this:

 class MyCellRenderer extends JLabel implements ListCellRenderer {
     public MyCellRenderer() {
         setOpaque(true);
     }

     public Component getListCellRendererComponent(JList list,
                                                   Object value,
                                                   int index,
                                                   boolean isSelected,
                                                   boolean cellHasFocus) {

         setText(value.toString());

         Color background;
         Color foreground;

         // check if this cell represents the current DnD drop location
         JList.DropLocation dropLocation = list.getDropLocation();
         if (dropLocation != null
                 && !dropLocation.isInsert()
                 && dropLocation.getIndex() == index) {

             background = Color.BLUE;
             foreground = Color.WHITE;

         // check if this cell is selected
         } else if (isSelected) {
             background = Color.RED;
             foreground = Color.WHITE;

         // unselected, and not the DnD drop location
         } else {
             background = Color.WHITE;
             foreground = Color.BLACK;
         };

         setBackground(background);
         setForeground(foreground);

         return this;
     }
 }
 

Summary

Public Methods
abstract Component getListCellRendererComponent(JList list, Object value, int index, boolean isSelected, boolean cellHasFocus)
Return a component that has been configured to display the specified value.

Public Methods

public abstract Component getListCellRendererComponent (JList list, Object value, int index, boolean isSelected, boolean cellHasFocus)

Return a component that has been configured to display the specified value. That component's paint method is then called to "render" the cell. If it is necessary to compute the dimensions of a list because the list cells do not have a fixed size, this method is called to generate a component on which getPreferredSize can be invoked.

Parameters
list The JList we're painting.
value The value returned by list.getModel().getElementAt(index).
index The cells index.
isSelected True if the specified cell was selected.
cellHasFocus True if the specified cell has the focus.
Returns
  • A component whose paint() method will render the specified value.