public class

CellRendererPane

extends Container
implements Accessible
java.lang.Object
   ↳ java.awt.Component
     ↳ java.awt.Container
       ↳ javax.swing.CellRendererPane

Class Overview

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: 

   cellRendererPane = new CellRendererPane();
   ...
   Component rendererComponent = renderer.getListCellRendererComponent();
   renderer.configureListCellRenderer(dataModel.getElementAt(row), row);
   cellRendererPane.paintComponent(g, rendererComponent, this, x, y, w, h);

A renderer component must override isShowing() and unconditionally return true to work correctly because the Swing paint does nothing for components with isShowing false.

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 JavaBeansTM has been added to the java.beans package. Please see XMLEncoder.

Summary

Nested Classes
class CellRendererPane.AccessibleCellRendererPane This class implements accessibility support for the CellRendererPane class. 
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Inherited Constants
From class java.awt.Component
From interface java.awt.image.ImageObserver
Fields
protected AccessibleContext accessibleContext
Public Constructors
CellRendererPane()
Construct a CellRendererPane object.
Public Methods
AccessibleContext getAccessibleContext()
Gets the AccessibleContext associated with this CellRendererPane.
void invalidate()
Overridden to avoid propagating a invalidate up the tree when the cell renderer child is configured.
void paint(Graphics g)
Shouldn't be called.
void paintComponent(Graphics g, Component c, Container p, Rectangle r)
Calls this.paintComponent() with the rectangles x,y,width,height fields.
void paintComponent(Graphics g, Component c, Container p, int x, int y, int w, int h, boolean shouldValidate)
Paint a cell renderer component c on graphics object g.
void paintComponent(Graphics g, Component c, Container p, int x, int y, int w, int h)
Calls this.paintComponent(g, c, p, x, y, w, h, false).
void update(Graphics g)
Shouldn't be called.
Protected Methods
void addImpl(Component x, Object constraints, int index)
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).
[Expand]
Inherited Methods
From class java.awt.Container
From class java.awt.Component
From class java.lang.Object
From interface java.awt.MenuContainer
From interface java.awt.image.ImageObserver
From interface javax.accessibility.Accessible

Fields

protected AccessibleContext accessibleContext

Public Constructors

public CellRendererPane ()

Construct a CellRendererPane object.

Public Methods

public AccessibleContext getAccessibleContext ()

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.

Returns
  • an AccessibleCellRendererPane that serves as the AccessibleContext of this CellRendererPane

public void invalidate ()

Overridden to avoid propagating a invalidate up the tree when the cell renderer child is configured.

public void paint (Graphics g)

Shouldn't be called.

Parameters
g the specified Graphics window

public void paintComponent (Graphics g, Component c, Container p, Rectangle r)

Calls this.paintComponent() with the rectangles x,y,width,height fields.

public void paintComponent (Graphics g, Component c, Container p, int x, int y, int w, int h, boolean shouldValidate)

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)

Calls this.paintComponent(g, c, p, x, y, w, h, false).

public void update (Graphics g)

Shouldn't be called.

Parameters
g the specified Graphics window

Protected Methods

protected void addImpl (Component x, Object constraints, int index)

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).<

Parameters
x the component to be added
constraints an object expressing layout constraints for this component
index the position in the container's list at which to insert the component, where -1 means append to the end