com.portal.ctrl

Class PBreadCrumbs

java.lang.Object

java.awt.Component

java.awt.Container

javax.swing.JComponent

javax.swing.JPanel

com.portal.ctrl.PBreadCrumbs

All Implemented Interfaces:

ActionListener, ImageObserver, MenuContainer, Serializable, EventListener, Accessible

public class PBreadCrumbs
extends JPanel
implements ActionListener

This component provides a visual trail (in the form of selectable links) reflecting the pages viewed by the user. In a GUI where a user can "drill down" from one screen to another, this component provides a visual cue as to where you are, where you came from, and a mechanism to get back.
Each time the user drills down, another breadcrumb (link) is added to the trail. The user can then pop back up by clicking on any of those breadcrumbs. Selecting the initial (first) link in the trail will take the user back to the initial screen and cause all links to be removed from the breadcrumb trail.
When a link is selected indicating the user wishes to "pop back", a vetoable property change event is sent out to any registered listeners. If the event is vetoed the selection is ignored and you will remain on the current link.

Author:

kapono

See Also:

Serialized Form

Nested Class Summary

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

JPanel.AccessibleJPanel

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

Fields

Modifier and Type	Field and Description
static String	LINK_CHANGE The vetoable property that is sent out before popping up in the trail when a link is selected.

Fields inherited from class javax.swing.JComponent

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

accessibleContext, 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

Constructors

Constructor and Description
PBreadCrumbs() Instantiates the breadcrumb component

Method Summary

Modifier and Type	Method and Description
void	actionPerformed(ActionEvent ae) Internal listener for link selection events
void	addActionListener(ActionListener l) Used to notify the ActionListener that a link was selected in the trail
void	addLink(String tag) Adds a link (breadcrumb) to the trail and establishes this link as the current location.
void	clear() Removes all links from the trail
boolean	contains(String tag) Used to determine if the given link name is contained in the breadcrumb trail
void	establishLinks(Enumeration enumElems) Takes the Strings contained in the Enumeration and creates a brand new breadcrumb trail from it.
String	getCurrentLink() Retrieves the current link tag
Enumeration	getLinks() Retrieves the current links in the trail.
String	getRoot() Retrieves the base tag for the breadcrumb trail.
void	moveToPreviousLink() A mechanism to navigate back to the previous link (breadcrumb).
void	removeActionListener(ActionListener l) Remove the listener from link selection notification
boolean	setCurrentLink(String tag) A mechanism to navigate backwards to the given link (breadcrumb).
void	setRoot(String tag) Establishes the base tag for the breadcrumb trail.

Methods inherited from class javax.swing.JPanel

getAccessibleContext, getUI, getUIClassID, paramString, setUI, updateUI

Methods inherited from class javax.swing.JComponent

addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, firePropertyChange, 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, getPreferredSize, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, isValidateRoot, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, scrollRectToVisible, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setFont, 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, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, 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, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, 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, imageUpdate, 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, repaint, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle

Methods inherited from class java.lang.Object

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

Field Detail

LINK_CHANGE

public static final String LINK_CHANGE

The vetoable property that is sent out before popping up in the trail when a link is selected.

See Also:

Constant Field Values

Constructor Detail

PBreadCrumbs

public PBreadCrumbs()

Instantiates the breadcrumb component

Method Detail

setRoot

public void setRoot(String tag)

Establishes the base tag for the breadcrumb trail. This should be the tag for the screen that appears initially. The user will not see this tag/link until they drill down since they are not able to use this link for navigation until they have switched to another component.

Parameters:

tag - The tag for the root link in the trail.

getRoot

public String getRoot()

Retrieves the base tag for the breadcrumb trail.

Returns:

The base tag for the breadcrumb trail.

getCurrentLink

public String getCurrentLink()

Retrieves the current link tag

Returns:

The tag for the current link; null if there is no link

setCurrentLink

public boolean setCurrentLink(String tag)

A mechanism to navigate backwards to the given link (breadcrumb). An attempt will be made to locate the given link by traversing backwards up the trail. If the given link is located all links between the current link and the given link will be removed.

Parameters:

tag - The name/text of the link to locate

Returns:

true if the move was successful; false otherwise

getLinks

public Enumeration getLinks()

Retrieves the current links in the trail. Note that the Enumeration will contain the original text for each link - the separator will be removed.

Returns:

An Enumeration containing all the links currently in the trail.

establishLinks

public void establishLinks(Enumeration enumElems)
                    throws IllegalArgumentException

Takes the Strings contained in the Enumeration and creates a brand new breadcrumb trail from it. Any existing trail is cleared prior to the new trail being created.
This method will verify that the first link in the Enumeration matches the breadcrumb root. If it does not match, this method will throw an IllegalArgumentException.

Throws:

IllegalArgumentException

addLink

public void addLink(String tag)

Adds a link (breadcrumb) to the trail and establishes this link as the current location. The current location is non-selectable and will be presented non-underlined in a different color than the links.

Parameters:

tag - The text to display in the link

addActionListener

public void addActionListener(ActionListener l)

Used to notify the ActionListener that a link was selected in the trail

Parameters:

l - The ActionListener

removeActionListener

public void removeActionListener(ActionListener l)

Remove the listener from link selection notification

Parameters:

l - The ActionListener

moveToPreviousLink

public void moveToPreviousLink()

A mechanism to navigate back to the previous link (breadcrumb). If you move back to the root, everything in the breadcrumb trail will be removed. An ActionEvent will be delivered to all listeners indicating the new current link (replicating user selection).

clear

public void clear()

Removes all links from the trail

contains

public boolean contains(String tag)

Used to determine if the given link name is contained in the breadcrumb trail

Parameters:

tag - The link to search for

Returns:

true if the trail contains the given link; false otherwise

actionPerformed

public void actionPerformed(ActionEvent ae)

Internal listener for link selection events

Specified by:

actionPerformed in interface ActionListener

Parameters:

ae - The action event