/*
* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*
*/
package javax.swing;
import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.beans.
PropertyChangeListener;
import java.util.
Locale;
import java.util.
Vector;
import javax.accessibility.*;
/**
* This class is inserted in between cell renderers and the components that
* use them. It just exists to thwart the repaint() and invalidate() methods
* which would otherwise propagate up the tree when the renderer was configured.
* It's used by the implementations of JTable, JTree, and JList. For example,
* here's how CellRendererPane is used in the code the paints each row
* in a JList:
* <pre>
* cellRendererPane = new CellRendererPane();
* ...
* Component rendererComponent = renderer.getListCellRendererComponent();
* renderer.configureListCellRenderer(dataModel.getElementAt(row), row);
* cellRendererPane.paintComponent(g, rendererComponent, this, x, y, w, h);
* </pre>
* <p>
* A renderer component must override isShowing() and unconditionally return
* true to work correctly because the Swing paint does nothing for components
* with isShowing false.
* <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™
* has been added to the <code>java.beans</code> package.
* Please see {@link java.beans.XMLEncoder}.
*
* @author Hans Muller
*/
public class
CellRendererPane extends
Container implements
Accessible
{
/**
* Construct a CellRendererPane object.
*/
public
CellRendererPane() {
super();
setLayout(null);
setVisible(false);
}
/**
* Overridden to avoid propagating a invalidate up the tree when the
* cell renderer child is configured.
*/
public void
invalidate() { }
/**
* Shouldn't be called.
*/
public void
paint(
Graphics g) { }
/**
* Shouldn't be called.
*/
public void
update(
Graphics g) { }
/**
* If the specified component is already a child of this then we don't
* bother doing anything - stacking order doesn't matter for cell
* renderer components (CellRendererPane doesn't paint anyway).
*/
protected void
addImpl(
Component x,
Object constraints, int
index) {
if (
x.
getParent() == this) {
return;
}
else {
super.addImpl(
x,
constraints,
index);
}
}
/**
* Paint a cell renderer component c on graphics object g. Before the component
* is drawn it's reparented to this (if that's necessary), it's bounds
* are set to w,h and the graphics object is (effectively) translated to x,y.
* If it's a JComponent, double buffering is temporarily turned off. After
* the component is painted it's bounds are reset to -w, -h, 0, 0 so that, if
* it's the last renderer component painted, it will not start consuming input.
* The Container p is the component we're actually drawing on, typically it's
* equal to this.getParent(). If shouldValidate is true the component c will be
* validated before painted.
*/
public void
paintComponent(
Graphics g,
Component c,
Container p, int
x, int
y, int
w, int
h, boolean
shouldValidate) {
if (
c == null) {
if (
p != null) {
Color oldColor =
g.
getColor();
g.
setColor(
p.
getBackground());
g.
fillRect(
x,
y,
w,
h);
g.
setColor(
oldColor);
}
return;
}
if (
c.
getParent() != this) {
this.
add(
c);
}
c.
setBounds(
x,
y,
w,
h);
if(
shouldValidate) {
c.
validate();
}
boolean
wasDoubleBuffered = false;
if ((
c instanceof
JComponent) && ((
JComponent)
c).
isDoubleBuffered()) {
wasDoubleBuffered = true;
((
JComponent)
c).
setDoubleBuffered(false);
}
Graphics cg =
g.
create(
x,
y,
w,
h);
try {
c.
paint(
cg);
}
finally {
cg.
dispose();
}
if (
wasDoubleBuffered && (
c instanceof
JComponent)) {
((
JComponent)
c).
setDoubleBuffered(true);
}
c.
setBounds(-
w, -
h, 0, 0);
}
/**
* Calls this.paintComponent(g, c, p, x, y, w, h, false).
*/
public void
paintComponent(
Graphics g,
Component c,
Container p, int
x, int
y, int
w, int
h) {
paintComponent(
g,
c,
p,
x,
y,
w,
h, false);
}
/**
* Calls this.paintComponent() with the rectangles x,y,width,height fields.
*/
public void
paintComponent(
Graphics g,
Component c,
Container p,
Rectangle r) {
paintComponent(
g,
c,
p,
r.
x,
r.
y,
r.
width,
r.
height);
}
private void
writeObject(
ObjectOutputStream s) throws
IOException {
removeAll();
s.
defaultWriteObject();
}
/////////////////
// Accessibility support
////////////////
protected
AccessibleContext accessibleContext = null;
/**
* Gets the AccessibleContext associated with this CellRendererPane.
* For CellRendererPanes, the AccessibleContext takes the form of an
* AccessibleCellRendererPane.
* A new AccessibleCellRendererPane instance is created if necessary.
*
* @return an AccessibleCellRendererPane that serves as the
* AccessibleContext of this CellRendererPane
*/
public
AccessibleContext getAccessibleContext() {
if (
accessibleContext == null) {
accessibleContext = new
AccessibleCellRendererPane();
}
return
accessibleContext;
}
/**
* This class implements accessibility support for the
* <code>CellRendererPane</code> class.
*/
protected class
AccessibleCellRendererPane extends
AccessibleAWTContainer {
// AccessibleContext methods
//
/**
* Get the role of this object.
*
* @return an instance of AccessibleRole describing the role of the
* object
* @see AccessibleRole
*/
public
AccessibleRole getAccessibleRole() {
return
AccessibleRole.
PANEL;
}
} // inner class AccessibleCellRendererPane
}