javax.swing
Class JPanel

java.lang.Object
  java.awt.Component
      java.awt.Container
          javax.swing.JComponent
              javax.swing.JPanel

All Implemented Interfaces:

javax.accessibility.Accessible, ImageObserver, MenuContainer, Serializable

Direct Known Subclasses:

AbstractColorChooserPanel, BasicTabbedPaneUI.ScrollableTabPanel, DefaultPreviewPanel, JSpinner.DefaultEditor, SwatchPanel

public class JPanel

extends JComponent

implements javax.accessibility.Accessible

JPanel is a generic lightweight container. For examples and task-oriented documentation for JPanel, see How to Use Panels, a section in The Java Tutorial.

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

Author:

Arnaud Weber, Steve Wilson

See Also:

Serialized Form

Nested Class Summary

protected class

JPanel.AccessibleJPanel This class implements accessibility support for the JPanel class.

Nested classes inherited from class javax.swing.JComponent

JComponent.AccessibleJComponent, JComponent.ActionStandin, JComponent.IntVector, JComponent.KeyboardState

Nested classes inherited from class java.awt.Container

Container.AccessibleAWTContainer

Nested classes inherited from class java.awt.Component

Component.AccessibleAWTComponent, Component.BltBufferStrategy, Component.FlipBufferStrategy

Field Summary

private static String

uiClassID

Fields inherited from class javax.swing.JComponent

_bounds, accessibleContext, listenerList, paintingChild, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW

Fields inherited from class java.awt.Container

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface java.awt.image.ImageObserver

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

Constructor Summary

JPanel()
Creates a new JPanel with a double buffer and a flow layout.

JPanel(boolean isDoubleBuffered)
Creates a new JPanel with FlowLayout and the specified buffering strategy.

JPanel(LayoutManager layout)
Create a new buffered JPanel with the specified layout manager

JPanel(LayoutManager layout, boolean isDoubleBuffered)
Creates a new JPanel with the specified layout manager and buffering strategy.

Method Summary

javax.accessibility.AccessibleContext	getAccessibleContext() Gets the AccessibleContext associated with this JPanel.
PanelUI	getUI() Returns the look and feel (L&F) object that renders this component.
String	getUIClassID() Returns a string that specifies the name of the L&F class that renders this component.
protected String	paramString() Returns a string representation of this JPanel.
void	setUI(PanelUI ui) Sets the look and feel (L&F) object that renders this component.
void	updateUI() Resets the UI property with a value from the current look and feel.
private void	writeObject(ObjectOutputStream s) See readObject() and writeObject() in JComponent for more information about serialization in Swing.

Methods inherited from class javax.swing.JComponent

_paintImmediately, addAncestorListener, addNotify, addPropertyChangeListener, addPropertyChangeListener, addVetoableChangeListener, alwaysOnTop, checkIfChildObscuredBySibling, componentInputMapChanged, computeVisibleRect, computeVisibleRect, compWriteObjectNotify, contains, createToolTip, disable, enable, enableSerialization, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBorder, getBounds, getClientProperty, getComponentGraphics, getConditionForKeyStroke, getCreatedDoubleBuffer, getDebugGraphicsOptions, getDefaultLocale, getGraphics, getHeight, getInputMap, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getManagingFocusBackwardTraversalKeys, getManagingFocusForwardTraversalKeys, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPreferredSize, getPropertyChangeListeners, getPropertyChangeListeners, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getWriteObjCounter, getX, getY, grabFocus, isDoubleBuffered, isLightweightComponent, isManagingFocus, isMaximumSizeSet, isMinimumSizeSet, isOpaque, isOptimizedDrawingEnabled, isPaintingOrigin, isPaintingTile, isPreferredSizeSet, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyBindings, processKeyBindingsForAllComponents, processKeyEvent, processMouseMotionEvent, putClientProperty, rectangleIsObscured, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removePropertyChangeListener, removePropertyChangeListener, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setCreatedDoubleBuffer, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFont, setForeground, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPaintingChild, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, setWriteObjCounter, shouldDebugGraphics, superProcessMouseMotionEvent, unregisterKeyboardAction, update

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setFocusCycleRoot, setFocusTraversalKeys, setFocusTraversalPolicy, setLayout, transferFocusBackward, transferFocusDownCycle, validate, validateTree

Methods inherited from class java.awt.Component

action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getFontMetrics, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMouseWheelListeners, getName, getParent, getPeer, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, hide, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, repaint, repaint, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusUpCycle

Methods inherited from class java.lang.Object

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

Field Detail

uiClassID

private static final String uiClassID

See Also:

getUIClassID(), JComponent.readObject(java.io.ObjectInputStream), Constant Field Values

Constructor Detail

JPanel

public JPanel(LayoutManager layout,
              boolean isDoubleBuffered)

Creates a new JPanel with the specified layout manager and buffering strategy.

Parameters:

layout - the LayoutManager to use

isDoubleBuffered - a boolean, true for double-buffering, which uses additional memory space to achieve fast, flicker-free updates

JPanel

public JPanel(LayoutManager layout)

Create a new buffered JPanel with the specified layout manager

Parameters:

layout - the LayoutManager to use

JPanel

public JPanel(boolean isDoubleBuffered)

Creates a new JPanel with FlowLayout and the specified buffering strategy. If isDoubleBuffered is true, the JPanel will use a double buffer.

Parameters:

isDoubleBuffered - a boolean, true for double-buffering, which uses additional memory space to achieve fast, flicker-free updates

JPanel

public JPanel()

Creates a new JPanel with a double buffer and a flow layout.

Method Detail

updateUI

public void updateUI()

Resets the UI property with a value from the current look and feel.

Overrides:

updateUI in class JComponent

See Also:

JComponent.updateUI()

getUI

public PanelUI getUI()

Returns the look and feel (L&F) object that renders this component.

Returns:

the PanelUI object that renders this component

Since:

1.4

setUI

public void setUI(PanelUI ui)

Sets the look and feel (L&F) object that renders this component.

Parameters:

ui - the PanelUI L&F object

Since:

1.4

See Also:

UIDefaults.getUI(javax.swing.JComponent)

getUIClassID

public String getUIClassID()

Returns a string that specifies the name of the L&F class that renders this component.

Overrides:

getUIClassID in class JComponent

Returns:

"PanelUI"

See Also:

JComponent.getUIClassID(), UIDefaults.getUI(javax.swing.JComponent)

writeObject

private void writeObject(ObjectOutputStream s)
                  throws IOException

See readObject() and writeObject() in JComponent for more information about serialization in Swing.

Throws:

IOException

paramString

protected String paramString()

Returns a string representation of this JPanel. This method is intended to be used only for debugging purposes, and the content and format of the returned string may vary between implementations. The returned string may be empty but may not be null.

Overrides:

paramString in class JComponent

Returns:

a string representation of this JPanel.

getAccessibleContext

public javax.accessibility.AccessibleContext getAccessibleContext()

Gets the AccessibleContext associated with this JPanel. For JPanels, the AccessibleContext takes the form of an AccessibleJPanel. A new AccessibleJPanel instance is created if necessary.

Specified by:

getAccessibleContext in interface javax.accessibility.Accessible

Overrides:

getAccessibleContext in class JComponent

Returns:

an AccessibleJPanel that serves as the AccessibleContext of this JPanel