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package javax.swing;

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.border.*;

import java.awt.Component;
import java.awt.Color;
import java.awt.Rectangle;

import java.io.Serializable;
import sun.swing.DefaultLookup;


Renders an item in a list.

Implementation Note: This class overrides invalidate, validate, revalidate, repaint, isOpaque, and firePropertyChange solely to improve performance. If not overridden, these frequently called methods would execute code paths that are unnecessary for the default list cell renderer. If you write your own renderer, take care to weigh the benefits and drawbacks of overriding these methods.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans™ has been added to the java.beans package. Please see XMLEncoder.

Author:Philip Milne, Hans Muller
/** * Renders an item in a list. * <p> * <strong><a name="override">Implementation Note:</a></strong> * This class overrides * <code>invalidate</code>, * <code>validate</code>, * <code>revalidate</code>, * <code>repaint</code>, * <code>isOpaque</code>, * and * <code>firePropertyChange</code> * solely to improve performance. * If not overridden, these frequently called methods would execute code paths * that are unnecessary for the default list cell renderer. * If you write your own renderer, * take care to weigh the benefits and * drawbacks of overriding these methods. * * <p> * * <strong>Warning:</strong> * Serialized objects of this class will not be compatible with * future Swing releases. The current serialization support is * appropriate for short term storage or RMI between applications running * the same version of Swing. As of 1.4, support for long term storage * of all JavaBeans&trade; * has been added to the <code>java.beans</code> package. * Please see {@link java.beans.XMLEncoder}. * * @author Philip Milne * @author Hans Muller */
public class DefaultListCellRenderer extends JLabel implements ListCellRenderer<Object>, Serializable {
An empty Border. This field might not be used. To change the Border used by this renderer override the getListCellRendererComponent method and set the border of the returned component directly.
/** * An empty <code>Border</code>. This field might not be used. To change the * <code>Border</code> used by this renderer override the * <code>getListCellRendererComponent</code> method and set the border * of the returned component directly. */
private static final Border SAFE_NO_FOCUS_BORDER = new EmptyBorder(1, 1, 1, 1); private static final Border DEFAULT_NO_FOCUS_BORDER = new EmptyBorder(1, 1, 1, 1); protected static Border noFocusBorder = DEFAULT_NO_FOCUS_BORDER;
Constructs a default renderer object for an item in a list.
/** * Constructs a default renderer object for an item * in a list. */
public DefaultListCellRenderer() { super(); setOpaque(true); setBorder(getNoFocusBorder()); setName("List.cellRenderer"); } private Border getNoFocusBorder() { Border border = DefaultLookup.getBorder(this, ui, "List.cellNoFocusBorder"); if (System.getSecurityManager() != null) { if (border != null) return border; return SAFE_NO_FOCUS_BORDER; } else { if (border != null && (noFocusBorder == null || noFocusBorder == DEFAULT_NO_FOCUS_BORDER)) { return border; } return noFocusBorder; } } public Component getListCellRendererComponent( JList<?> list, Object value, int index, boolean isSelected, boolean cellHasFocus) { setComponentOrientation(list.getComponentOrientation()); Color bg = null; Color fg = null; JList.DropLocation dropLocation = list.getDropLocation(); if (dropLocation != null && !dropLocation.isInsert() && dropLocation.getIndex() == index) { bg = DefaultLookup.getColor(this, ui, "List.dropCellBackground"); fg = DefaultLookup.getColor(this, ui, "List.dropCellForeground"); isSelected = true; } if (isSelected) { setBackground(bg == null ? list.getSelectionBackground() : bg); setForeground(fg == null ? list.getSelectionForeground() : fg); } else { setBackground(list.getBackground()); setForeground(list.getForeground()); } if (value instanceof Icon) { setIcon((Icon)value); setText(""); } else { setIcon(null); setText((value == null) ? "" : value.toString()); } setEnabled(list.isEnabled()); setFont(list.getFont()); Border border = null; if (cellHasFocus) { if (isSelected) { border = DefaultLookup.getBorder(this, ui, "List.focusSelectedCellHighlightBorder"); } if (border == null) { border = DefaultLookup.getBorder(this, ui, "List.focusCellHighlightBorder"); } } else { border = getNoFocusBorder(); } setBorder(border); return this; }
Overridden for performance reasons. See the Implementation Note for more information.
Since:1.5
Returns:true if the background is completely opaque and differs from the JList's background; false otherwise
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. * * @since 1.5 * @return <code>true</code> if the background is completely opaque * and differs from the JList's background; * <code>false</code> otherwise */
@Override public boolean isOpaque() { Color back = getBackground(); Component p = getParent(); if (p != null) { p = p.getParent(); } // p should now be the JList. boolean colorMatch = (back != null) && (p != null) && back.equals(p.getBackground()) && p.isOpaque(); return !colorMatch && super.isOpaque(); }
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void validate() {}
Overridden for performance reasons. See the Implementation Note for more information.
Since:1.5
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. * * @since 1.5 */
@Override public void invalidate() {}
Overridden for performance reasons. See the Implementation Note for more information.
Since:1.5
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. * * @since 1.5 */
@Override public void repaint() {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void revalidate() {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void repaint(long tm, int x, int y, int width, int height) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void repaint(Rectangle r) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override protected void firePropertyChange(String propertyName, Object oldValue, Object newValue) { // Strings get interned... if (propertyName == "text" || ((propertyName == "font" || propertyName == "foreground") && oldValue != newValue && getClientProperty(javax.swing.plaf.basic.BasicHTML.propertyKey) != null)) { super.firePropertyChange(propertyName, oldValue, newValue); } }
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, byte oldValue, byte newValue) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, char oldValue, char newValue) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, short oldValue, short newValue) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, int oldValue, int newValue) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, long oldValue, long newValue) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, float oldValue, float newValue) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, double oldValue, double newValue) {}
Overridden for performance reasons. See the Implementation Note for more information.
/** * Overridden for performance reasons. * See the <a href="#override">Implementation Note</a> * for more information. */
@Override public void firePropertyChange(String propertyName, boolean oldValue, boolean newValue) {}
A subclass of DefaultListCellRenderer that implements UIResource. DefaultListCellRenderer doesn't implement UIResource directly so that applications can safely override the cellRenderer property with DefaultListCellRenderer subclasses.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans™ has been added to the java.beans package. Please see XMLEncoder.

/** * A subclass of DefaultListCellRenderer that implements UIResource. * DefaultListCellRenderer doesn't implement UIResource * directly so that applications can safely override the * cellRenderer property with DefaultListCellRenderer subclasses. * <p> * <strong>Warning:</strong> * Serialized objects of this class will not be compatible with * future Swing releases. The current serialization support is * appropriate for short term storage or RMI between applications running * the same version of Swing. As of 1.4, support for long term storage * of all JavaBeans&trade; * has been added to the <code>java.beans</code> package. * Please see {@link java.beans.XMLEncoder}. */
public static class UIResource extends DefaultListCellRenderer implements javax.swing.plaf.UIResource { } }