Module java.desktop

Package javax.swing

Class CellRendererPane

java.lang.Object

java.awt.Component

java.awt.Container

javax.swing.CellRendererPane

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible

public class CellRendererPane
extends Container
implements Accessible

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

Since:

1.2

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
protected class	CellRendererPane.AccessibleCellRendererPane	This class implements accessibility support for the CellRendererPane class.

Nested classes/interfaces declared in class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces declared in class java.awt.Component

Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

Fields

Modifier and Type	Field	Description
protected AccessibleContext	accessibleContext	AccessibleContext associated with this CellRendererPan

Fields declared in class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields declared in interface java.awt.image.ImageObserver

ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH

Constructor Summary

Constructors

Constructor	Description
CellRendererPane()	Construct a CellRendererPane object.

Method Summary

Modifier and Type	Method	Description
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).
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, int x, int y, int w, int h)	Calls this.paintComponent(g, c, p, x, y, w, h, false).
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, Rectangle r)	Calls this.paintComponent(g, c, p, r.x, r.y, r.width, r.height) where r is the input Rectangle parameter.
void	update(Graphics g)	Shouldn't be called.

Methods declared in class java.awt.Container

add, add, add, add, add, addContainerListener, addNotify, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getAlignmentX, getAlignmentY, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getInsets, getLayout, getListeners, getMaximumSize, getMinimumSize, getMousePosition, getPreferredSize, insets, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, isValidateRoot, layout, list, list, locate, minimumSize, paintComponents, paramString, preferredSize, print, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, removeNotify, setComponentZOrder, setFocusCycleRoot, setFocusTraversalKeys, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setFont, setLayout, transferFocusDownCycle, validate, validateTree

Methods declared in class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, contains, createImage, createImage, createVolatileImage, createVolatileImage, disable, disableEvents, dispatchEvent, enable, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBaseline, getBaselineResizeBehavior, getBounds, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphics, getGraphicsConfiguration, getHeight, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getSize, getToolkit, getTreeLock, getWidth, getX, getY, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isDoubleBuffered, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, printAll, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processKeyEvent, processMouseEvent, processMouseMotionEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, repaint, requestFocus, requestFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, requestFocusInWindow, reshape, resize, resize, revalidate, setBackground, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setEnabled, setFocusable, setFocusTraversalKeysEnabled, setForeground, setIgnoreRepaint, setLocale, setLocation, setLocation, setMaximumSize, setMinimumSize, setMixingCutoutShape, setName, setPreferredSize, setSize, setSize, setVisible, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods declared in class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Details

accessibleContext

protected AccessibleContext accessibleContext

AccessibleContext associated with this CellRendererPan

Constructor Details

CellRendererPane

public CellRendererPane()

Construct a CellRendererPane object.

Method Details

invalidate

public void invalidate()

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

Overrides:

invalidate in class Container

See Also:

• Container.validate()
• Container.layout()
• LayoutManager2

paint

public void paint(Graphics g)

Shouldn't be called.

Overrides:

paint in class Container

Parameters:

g - the specified Graphics window

See Also:

• Component.update(Graphics)

update

public void update(Graphics g)

Shouldn't be called.

Overrides:

update in class Container

Parameters:

g - the specified Graphics window

See Also:

• Component.update(Graphics)

addImpl

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).

Overrides:

addImpl in class Container

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

See Also:

• Container.add(Component)
• Container.add(Component, int)
• Container.add(Component, java.lang.Object)
• Container.invalidate()
• LayoutManager
• LayoutManager2

paintComponent

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.

Parameters:

g - the Graphics object to draw on

c - the Component to draw

p - the Container component actually drawn on

x - an int specifying the left side of the area draw in, in pixels, measured from the left edge of the graphics context

y - an int specifying the top of the area to draw in, in pixels measured down from the top edge of the graphics context

w - an int specifying the width of the area draw in, in pixels

h - an int specifying the height of the area draw in, in pixels

shouldValidate - if true, component c will be validated before being painted

paintComponent

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).

Parameters:

g - the Graphics object to draw on

c - the Component to draw

p - the Container component actually drawn on

x - an int specifying the left side of the area draw in, in pixels, measured from the left edge of the graphics context

y - an int specifying the top of the area to draw in, in pixels measured down from the top edge of the graphics context

w - an int specifying the width of the area draw in, in pixels

h - an int specifying the height of the area draw in, in pixels

paintComponent

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

Calls this.paintComponent(g, c, p, r.x, r.y, r.width, r.height) where r is the input Rectangle parameter.

Parameters:

g - the Graphics object to draw on

c - the Component to draw

p - the Container component actually drawn on

r - the Rectangle to draw in

getAccessibleContext

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.

Specified by:

getAccessibleContext in interface Accessible

Overrides:

getAccessibleContext in class Component

Returns:

an AccessibleCellRendererPane that serves as the AccessibleContext of this CellRendererPane