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javax.swing.tree
Class DefaultTreeCellRenderer

java.lang.Object
  java.awt.Component
      java.awt.Container
          javax.swing.JComponent
              javax.swing.JLabel
                  javax.swing.tree.DefaultTreeCellRenderer

All Implemented Interfaces:

ImageObserver, MenuContainer, Serializable, Accessible, SwingConstants, TreeCellRenderer

public class DefaultTreeCellRenderer
extends JLabel
implements TreeCellRenderer

Displays an entry in a tree. DefaultTreeCellRenderer is not opaque and unless you subclass paint you should not change this. See How to Use Trees in The Java Tutorial for examples of customizing node display using this class.

Implementation Note: This class overrides invalidate, validate, revalidate, repaint, and firePropertyChange solely to improve performance. If not overridden, these frequently called methods would execute code paths that are unnecessary for the default tree cell renderer. If you write your own renderer, take care to weigh the benefits and drawbacks of overriding these methods.

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.

Nested Class Summary

Nested classes/interfaces inherited from class javax.swing.JLabel

JLabel.AccessibleJLabel

Nested classes/interfaces inherited from class javax.swing.JComponent

JComponent.AccessibleJComponent

Nested classes/interfaces inherited from class java.awt.Container

Container.AccessibleAWTContainer

Nested classes/interfaces inherited from class java.awt.Component

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

Field Summary

protected Color	backgroundNonSelectionColor Color to use for the background when the node isn't selected.
protected Color	backgroundSelectionColor Color to use for the background when a node is selected.
protected Color	borderSelectionColor Color to use for the focus indicator when the node has focus.
protected Icon	closedIcon Icon used to show non-leaf nodes that aren't expanded.
protected boolean	hasFocus True if has focus.
protected Icon	leafIcon Icon used to show leaf nodes.
protected Icon	openIcon Icon used to show non-leaf nodes that are expanded.
protected boolean	selected Is the value currently selected.
protected Color	textNonSelectionColor Color to use for the foreground for non-selected nodes.
protected Color	textSelectionColor Color to use for the foreground for selected nodes.

Fields inherited from class javax.swing.JLabel

labelFor

Fields inherited from class javax.swing.JComponent

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

Fields inherited from class java.awt.Component

BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT

Fields inherited from interface javax.swing.SwingConstants

BOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WEST

Fields inherited from interface java.awt.image.ImageObserver

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

Constructor Summary

DefaultTreeCellRenderer()
Returns a new instance of DefaultTreeCellRenderer.

Method Summary

void	firePropertyChange(String propertyName, boolean oldValue, boolean newValue) Overridden for performance reasons.
void	firePropertyChange(String propertyName, byte oldValue, byte newValue) Overridden for performance reasons.
void	firePropertyChange(String propertyName, char oldValue, char newValue) Overridden for performance reasons.
void	firePropertyChange(String propertyName, double oldValue, double newValue) Overridden for performance reasons.
void	firePropertyChange(String propertyName, float oldValue, float newValue) Overridden for performance reasons.
void	firePropertyChange(String propertyName, int oldValue, int newValue) Overridden for performance reasons.
void	firePropertyChange(String propertyName, long oldValue, long newValue) Overridden for performance reasons.
protected void	firePropertyChange(String propertyName, Object oldValue, Object newValue) Overridden for performance reasons.
void	firePropertyChange(String propertyName, short oldValue, short newValue) Overridden for performance reasons.
Color	getBackgroundNonSelectionColor() Returns the background color to be used for non selected nodes.
Color	getBackgroundSelectionColor() Returns the color to use for the background if node is selected.
Color	getBorderSelectionColor() Returns the color the border is drawn.
Icon	getClosedIcon() Returns the icon used to represent non-leaf nodes that are not expanded.
Icon	getDefaultClosedIcon() Returns the default icon, for the current laf, that is used to represent non-leaf nodes that are not expanded.
Icon	getDefaultLeafIcon() Returns the default icon, for the current laf, that is used to represent leaf nodes.
Icon	getDefaultOpenIcon() Returns the default icon, for the current laf, that is used to represent non-leaf nodes that are expanded.
Font	getFont() Gets the font of this component.
Icon	getLeafIcon() Returns the icon used to represent leaf nodes.
Icon	getOpenIcon() Returns the icon used to represent non-leaf nodes that are expanded.
Dimension	getPreferredSize() Overrides JComponent.getPreferredSize to return slightly wider preferred size value.
Color	getTextNonSelectionColor() Returns the color the text is drawn with when the node isn't selected.
Color	getTextSelectionColor() Returns the color the text is drawn with when the node is selected.
Component	getTreeCellRendererComponent(JTree tree, Object value, boolean sel, boolean expanded, boolean leaf, int row, boolean hasFocus) Configures the renderer based on the passed in components.
void	invalidate() Overridden for performance reasons.
void	paint(Graphics g) Paints the value.
void	repaint() Overridden for performance reasons.
void	repaint(long tm, int x, int y, int width, int height) Overridden for performance reasons.
void	repaint(Rectangle r) Overridden for performance reasons.
void	revalidate() Overridden for performance reasons.
void	setBackground(Color color) Subclassed to map ColorUIResources to null.
void	setBackgroundNonSelectionColor(Color newColor) Sets the background color to be used for non selected nodes.
void	setBackgroundSelectionColor(Color newColor) Sets the color to use for the background if node is selected.
void	setBorderSelectionColor(Color newColor) Sets the color to use for the border.
void	setClosedIcon(Icon newIcon) Sets the icon used to represent non-leaf nodes that are not expanded.
void	setFont(Font font) Subclassed to map FontUIResources to null.
void	setLeafIcon(Icon newIcon) Sets the icon used to represent leaf nodes.
void	setOpenIcon(Icon newIcon) Sets the icon used to represent non-leaf nodes that are expanded.
void	setTextNonSelectionColor(Color newColor) Sets the color the text is drawn with when the node isn't selected.
void	setTextSelectionColor(Color newColor) Sets the color the text is drawn with when the node is selected.
void	validate() Overridden for performance reasons.

Methods inherited from class javax.swing.JLabel

checkHorizontalKey, checkVerticalKey, getAccessibleContext, getDisabledIcon, getDisplayedMnemonic, getDisplayedMnemonicIndex, getHorizontalAlignment, getHorizontalTextPosition, getIcon, getIconTextGap, getLabelFor, getText, getUI, getUIClassID, getVerticalAlignment, getVerticalTextPosition, imageUpdate, paramString, setDisabledIcon, setDisplayedMnemonic, setDisplayedMnemonic, setDisplayedMnemonicIndex, setHorizontalAlignment, setHorizontalTextPosition, setIcon, setIconTextGap, setLabelFor, setText, setUI, setVerticalAlignment, setVerticalTextPosition, updateUI

Methods inherited from class javax.swing.JComponent

addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update

Methods inherited from class java.awt.Container

add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusBackward, transferFocusDownCycle, 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, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getInputMethodRequests, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPeer, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, hide, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, 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, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, 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

selected

protected boolean selected

Is the value currently selected.

hasFocus

protected boolean hasFocus

True if has focus.

closedIcon

protected transient Icon closedIcon

Icon used to show non-leaf nodes that aren't expanded.

leafIcon

protected transient Icon leafIcon

Icon used to show leaf nodes.

openIcon

protected transient Icon openIcon

Icon used to show non-leaf nodes that are expanded.

textSelectionColor

protected Color textSelectionColor

Color to use for the foreground for selected nodes.

textNonSelectionColor

protected Color textNonSelectionColor

Color to use for the foreground for non-selected nodes.

backgroundSelectionColor

protected Color backgroundSelectionColor

Color to use for the background when a node is selected.

backgroundNonSelectionColor

protected Color backgroundNonSelectionColor

Color to use for the background when the node isn't selected.

borderSelectionColor

protected Color borderSelectionColor

Color to use for the focus indicator when the node has focus.

Constructor Detail

DefaultTreeCellRenderer

public DefaultTreeCellRenderer()

Returns a new instance of DefaultTreeCellRenderer. Alignment is set to left aligned. Icons and text color are determined from the UIManager.

Method Detail

getDefaultOpenIcon

public Icon getDefaultOpenIcon()

Returns the default icon, for the current laf, that is used to represent non-leaf nodes that are expanded.

getDefaultClosedIcon

public Icon getDefaultClosedIcon()

Returns the default icon, for the current laf, that is used to represent non-leaf nodes that are not expanded.

getDefaultLeafIcon

public Icon getDefaultLeafIcon()

Returns the default icon, for the current laf, that is used to represent leaf nodes.

setOpenIcon

public void setOpenIcon(Icon newIcon)

Sets the icon used to represent non-leaf nodes that are expanded.

getOpenIcon

public Icon getOpenIcon()

Returns the icon used to represent non-leaf nodes that are expanded.

setClosedIcon

public void setClosedIcon(Icon newIcon)

Sets the icon used to represent non-leaf nodes that are not expanded.

getClosedIcon

public Icon getClosedIcon()

Returns the icon used to represent non-leaf nodes that are not expanded.

setLeafIcon

public void setLeafIcon(Icon newIcon)

Sets the icon used to represent leaf nodes.

getLeafIcon

public Icon getLeafIcon()

Returns the icon used to represent leaf nodes.

setTextSelectionColor

public void setTextSelectionColor(Color newColor)

Sets the color the text is drawn with when the node is selected.

getTextSelectionColor

public Color getTextSelectionColor()

Returns the color the text is drawn with when the node is selected.

setTextNonSelectionColor

public void setTextNonSelectionColor(Color newColor)

Sets the color the text is drawn with when the node isn't selected.

getTextNonSelectionColor

public Color getTextNonSelectionColor()

Returns the color the text is drawn with when the node isn't selected.

setBackgroundSelectionColor

public void setBackgroundSelectionColor(Color newColor)

Sets the color to use for the background if node is selected.

getBackgroundSelectionColor

public Color getBackgroundSelectionColor()

Returns the color to use for the background if node is selected.

setBackgroundNonSelectionColor

public void setBackgroundNonSelectionColor(Color newColor)

Sets the background color to be used for non selected nodes.

getBackgroundNonSelectionColor

public Color getBackgroundNonSelectionColor()

Returns the background color to be used for non selected nodes.

setBorderSelectionColor

public void setBorderSelectionColor(Color newColor)

Sets the color to use for the border.

getBorderSelectionColor

public Color getBorderSelectionColor()

Returns the color the border is drawn.

setFont

public void setFont(Font font)

Subclassed to map FontUIResources to null. If font is null, or a FontUIResource, this has the effect of letting the font of the JTree show through. On the other hand, if font is non-null, and not a FontUIResource, the font becomes font.

Overrides:

setFont in class JComponent

Parameters:

font - the desired Font for this component

See Also:

Component.getFont()

getFont

public Font getFont()

Gets the font of this component.

Specified by:

getFont in interface MenuContainer

Overrides:

getFont in class Component

Returns:

this component's font; if a font has not been set for this component, the font of its parent is returned

See Also:

Component.setFont(java.awt.Font)

setBackground

public void setBackground(Color color)

Subclassed to map ColorUIResources to null. If color is null, or a ColorUIResource, this has the effect of letting the background color of the JTree show through. On the other hand, if color is non-null, and not a ColorUIResource, the background becomes color.

Overrides:

setBackground in class JComponent

Parameters:

color - the desired background Color

See Also:

Component.getBackground(), JComponent.setOpaque(boolean)

getTreeCellRendererComponent

public Component getTreeCellRendererComponent(JTree tree,
                                              Object value,
                                              boolean sel,
                                              boolean expanded,
                                              boolean leaf,
                                              int row,
                                              boolean hasFocus)

Configures the renderer based on the passed in components. The value is set from messaging the tree with convertValueToText, which ultimately invokes toString on value. The foreground color is set based on the selection and the icon is set based on the leaf and expanded parameters.

Specified by:

getTreeCellRendererComponent in interface TreeCellRenderer

Returns:

the Component that the renderer uses to draw the value

paint

public void paint(Graphics g)

Paints the value. The background is filled based on selected.

Overrides:

paint in class JComponent

Parameters:

g - the Graphics context in which to paint

See Also:

JComponent.paintComponent(java.awt.Graphics), JComponent.paintBorder(java.awt.Graphics), JComponent.paintChildren(java.awt.Graphics), JComponent.getComponentGraphics(java.awt.Graphics), JComponent.repaint(long, int, int, int, int)

getPreferredSize

public Dimension getPreferredSize()

Overrides JComponent.getPreferredSize to return slightly wider preferred size value.

Overrides:

getPreferredSize in class JComponent

Returns:

the value of the preferredSize property

See Also:

JComponent.setPreferredSize(java.awt.Dimension), ComponentUI

validate

public void validate()

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

validate in class Container

See Also:

Container.add(java.awt.Component), Component.invalidate(), JComponent.revalidate(), Container.validateTree()

invalidate

public void invalidate()

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

invalidate in class Container

Since:

1.5

See Also:

Container.validate(), Container.layout(), LayoutManager, LayoutManager2.invalidateLayout(Container)

revalidate

public void revalidate()

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

revalidate in class JComponent

See Also:

Component.invalidate(), Container.validate(), JComponent.isValidateRoot(), RepaintManager.addInvalidComponent(javax.swing.JComponent)

repaint

public void repaint(long tm,
                    int x,
                    int y,
                    int width,
                    int height)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

repaint in class JComponent

Parameters:

tm - this parameter is not used

x - the x value of the dirty region

y - the y value of the dirty region

width - the width of the dirty region

height - the height of the dirty region

See Also:

Component.isShowing(), RepaintManager.addDirtyRegion(javax.swing.JComponent, int, int, int, int)

repaint

public void repaint(Rectangle r)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

repaint in class JComponent

Parameters:

r - a Rectangle containing the dirty region

See Also:

Component.isShowing(), RepaintManager.addDirtyRegion(javax.swing.JComponent, int, int, int, int)

repaint

public void repaint()

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

repaint in class Component

Since:

1.5

See Also:

Component.update(Graphics)

firePropertyChange

protected void firePropertyChange(String propertyName,
                                  Object oldValue,
                                  Object newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class Component

Parameters:

propertyName - the property whose value has changed

oldValue - the property's previous value

newValue - the property's new value

firePropertyChange

public void firePropertyChange(String propertyName,
                               byte oldValue,
                               byte newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class Component

Parameters:

propertyName - the programmatic name of the property that was changed

oldValue - the old value of the property (as a byte)

newValue - the new value of the property (as a byte)

See Also:

Component.firePropertyChange(java.lang.String, java.lang.Object, java.lang.Object)

firePropertyChange

public void firePropertyChange(String propertyName,
                               char oldValue,
                               char newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class JComponent

Parameters:

propertyName - the programmatic name of the property that was changed

oldValue - the old value of the property (as a char)

newValue - the new value of the property (as a char)

See Also:

Component.firePropertyChange(java.lang.String, java.lang.Object, java.lang.Object)

firePropertyChange

public void firePropertyChange(String propertyName,
                               short oldValue,
                               short newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class Component

Parameters:

propertyName - the programmatic name of the property that was changed

oldValue - the old value of the property (as a short)

newValue - the old value of the property (as a short)

See Also:

Component.firePropertyChange(java.lang.String, java.lang.Object, java.lang.Object)

firePropertyChange

public void firePropertyChange(String propertyName,
                               int oldValue,
                               int newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class JComponent

Parameters:

propertyName - the property whose value has changed

oldValue - the property's previous value

newValue - the property's new value

firePropertyChange

public void firePropertyChange(String propertyName,
                               long oldValue,
                               long newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class Component

Parameters:

propertyName - the programmatic name of the property that was changed

oldValue - the old value of the property (as a long)

newValue - the new value of the property (as a long)

See Also:

Component.firePropertyChange(java.lang.String, java.lang.Object, java.lang.Object)

firePropertyChange

public void firePropertyChange(String propertyName,
                               float oldValue,
                               float newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class Component

Parameters:

propertyName - the programmatic name of the property that was changed

oldValue - the old value of the property (as a float)

newValue - the new value of the property (as a float)

See Also:

Component.firePropertyChange(java.lang.String, java.lang.Object, java.lang.Object)

firePropertyChange

public void firePropertyChange(String propertyName,
                               double oldValue,
                               double newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class Component

Parameters:

propertyName - the programmatic name of the property that was changed

oldValue - the old value of the property (as a double)

newValue - the new value of the property (as a double)

See Also:

Component.firePropertyChange(java.lang.String, java.lang.Object, java.lang.Object)

firePropertyChange

public void firePropertyChange(String propertyName,
                               boolean oldValue,
                               boolean newValue)

Overridden for performance reasons. See the Implementation Note for more information.

Overrides:

firePropertyChange in class JComponent

Parameters:

propertyName - the property whose value has changed

oldValue - the property's previous value

newValue - the property's new value