/*
* Copyright (c) 1998, 2007, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* 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.
*/
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.
* <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<sup><font size="-2">TM</font></sup>
* 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, Serializable
{
/**
* 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.
*/
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 <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 <a href="#override">Implementation Note</a>
* for more information.
*/
@Override
public void validate() {}
/**
* 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 <a href="#override">Implementation Note</a>
* for more information.
*
* @since 1.5
*/
@Override
public void repaint() {}
/**
* 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 <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 <a href="#override">Implementation Note</a>
* for more information.
*/
@Override
public void repaint(Rectangle r) {}
/**
* 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 <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 <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 <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 <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 <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 <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 <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 <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.
* <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<sup><font size="-2">TM</font></sup>
* 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
{
}
}