/*
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/**
* 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:
* <pre>
* {@code
* class MyCellRenderer extends JLabel implements ListCellRenderer<Object> {
* 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;
* }
* }
* }
* </pre>
*
* @param <E> the type of values this renderer can be used for
*
* @see JList
* @see DefaultListCellRenderer
*
* @author Hans Muller
*/
public interface ListCellRenderer<E>
{
/**
* Return a component that has been configured to display the specified
* value. That component's <code>paint</code> 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 <code>getPreferredSize</code>
* can be invoked.
*
* @param list The JList we're painting.
* @param value The value returned by list.getModel().getElementAt(index).
* @param index The cells index.
* @param isSelected True if the specified cell was selected.
* @param cellHasFocus True if the specified cell has the focus.
* @return A component whose paint() method will render the specified value.
*
* @see JList
* @see ListSelectionModel
* @see ListModel
*/
E value,
int index,
boolean isSelected,
boolean cellHasFocus);
}