org.w3c.tools.widgets
Class TreeBrowser

java.lang.Object
  java.awt.Component
      java.awt.Canvas
          org.w3c.tools.widgets.TreeBrowser

All Implemented Interfaces:

java.awt.event.AdjustmentListener, java.awt.image.ImageObserver, java.awt.MenuContainer, java.io.Serializable, java.util.EventListener, javax.accessibility.Accessible

Direct Known Subclasses:

FrameBrowser, ServerBrowser

public class TreeBrowser
extends java.awt.Canvas
implements java.awt.event.AdjustmentListener

The TreeBrowser class. This class is a generic framework to browser any hierachical structure.

Genericity is obtained through the use of 'handlers': the TreeBrowser itself does not perform any action in response to user events, but simply forward them as notifications to handlers. Each item inserted may have its own handler, but handlers may also (this is the most common case) be shared between handlers.

Any item added in the Tree is displayed with an icon and a label. When a handler receive a notification on a node, it may change this node, to modify or update its appearance.

See Also:

Serialized Form

Nested Class Summary

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

java.awt.Canvas.AccessibleAWTCanvas

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

java.awt.Component.AccessibleAWTComponent, java.awt.Component.BltBufferStrategy, java.awt.Component.FlipBufferStrategy

Field Summary

protected int	fontHeight
protected java.util.Vector	items
static int	MULTIPLE The policy that enables a multiple selection of nodes.
static int	SCROLLBARS_ALWAYS Specifies that the horizontal/vertical scrollbars should always be shown regardless of the respective sizes of the TreeBrowser.
static int	SCROLLBARS_ASNEEDED Specifies that horizontal/vertical scrollbars should be shown only when the size of the nodes exceeds the size of the TreeBrowser in the horizontal/vertical dimension.
protected java.util.Vector	selection
protected int	selectionPolicy
static int	SINGLE This policy that lets just one node selected at the same time.
protected int	topItem
protected int	visibleItemCount

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

protected	TreeBrowser()
	TreeBrowser(java.lang.Object root, java.lang.String label, NodeHandler handler, java.awt.Image icon) Builds a new browser instance

Method Summary

void	adjustmentValueChanged(java.awt.event.AdjustmentEvent evt) Updates graphical appearance in response to a scroll.
void	collapse(TreeNode item) Contracts the representation of the specified node.
TreeNode	getNode(java.lang.Object obj) Gets the node associated to the specified object, or null if any.
TreeNode	getParent(TreeNode child) Returns the parent node of the specified node.
java.awt.Dimension	getPreferredSize()
int	getSelectionPolicy() Gets the selection policy.
protected void	initialize(java.lang.Object item, java.lang.String label, NodeHandler handler, java.awt.Image icon)
void	insert(TreeNode parent, java.lang.Object item, NodeHandler handler, java.lang.String label, java.awt.Image icon) Inserts new node.
protected TreeNode	itemAt(int y) this should be private.
void	paint(java.awt.Graphics g) repaints the View.
void	remove(TreeNode node) Removes the specified node.
void	removeBranch(TreeNode node) Removes the specified node and its children.
void	select(TreeNode node) Selects the specified node.
java.util.Enumeration	selection() Returns an Enumeraiton of selected items.
void	setHorizontalScrollbar(java.awt.Scrollbar a) Sets 'a' as horizontal Scrollbar.
void	setScrollbarDisplayPolicy(int scrollbarDisplayPolicy) Sets the scrollbars display policy to the specified policy.
void	setSelectionBackgroudColor(java.awt.Color color) Sets the background color of a selected node to the specified color.
void	setSelectionFontColor(java.awt.Color color) Sets the color of a selected node to the specified color.
void	setSelectionPolicy(int policy) Sets the selection policy.
void	setVerticalScrollbar(java.awt.Scrollbar a) Sets 'a' as vertical Scrollbar.
void	unselect(TreeNode node) Unselects the specified node.
void	unselectAll() Unselects all selected items.
void	update(java.awt.Graphics pg)

Methods inherited from class java.awt.Canvas

addNotify, createBufferStrategy, createBufferStrategy, getAccessibleContext, getBufferStrategy

Methods inherited from class java.awt.Component

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

Methods inherited from class java.lang.Object

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

Field Detail

SCROLLBARS_ALWAYS

public static final int SCROLLBARS_ALWAYS

Specifies that the horizontal/vertical scrollbars should always be shown regardless of the respective sizes of the TreeBrowser.

See Also:

Constant Field Values

SCROLLBARS_ASNEEDED

public static final int SCROLLBARS_ASNEEDED

Specifies that horizontal/vertical scrollbars should be shown only when the size of the nodes exceeds the size of the TreeBrowser in the horizontal/vertical dimension.

See Also:

Constant Field Values

SINGLE

public static final int SINGLE

This policy that lets just one node selected at the same time.

See Also:

Constant Field Values

MULTIPLE

public static final int MULTIPLE

The policy that enables a multiple selection of nodes.

See Also:

Constant Field Values

items

protected java.util.Vector items

selection

protected java.util.Vector selection

topItem

protected int topItem

visibleItemCount

protected int visibleItemCount

selectionPolicy

protected int selectionPolicy

fontHeight

protected int fontHeight

Constructor Detail

TreeBrowser

public TreeBrowser(java.lang.Object root,
                   java.lang.String label,
                   NodeHandler handler,
                   java.awt.Image icon)

Builds a new browser instance

Parameters:

root - the root node for this hierarchy

label - the label that should be displayed for this item

handler - the handler for this node

icon - the icon that must be displayed for this item

TreeBrowser

protected TreeBrowser()

Method Detail

initialize

protected void initialize(java.lang.Object item,
                          java.lang.String label,
                          NodeHandler handler,
                          java.awt.Image icon)

getPreferredSize

public java.awt.Dimension getPreferredSize()

Overrides:

getPreferredSize in class java.awt.Component

setSelectionFontColor

public void setSelectionFontColor(java.awt.Color color)

Sets the color of a selected node to the specified color.

Parameters:

color - the color used to paint a selected node

setSelectionBackgroudColor

public void setSelectionBackgroudColor(java.awt.Color color)

Sets the background color of a selected node to the specified color.

Parameters:

color - the color used to paint the background of a selected node

setScrollbarDisplayPolicy

public void setScrollbarDisplayPolicy(int scrollbarDisplayPolicy)

Sets the scrollbars display policy to the specified policy. The default is SCROLLBARS_ALWAYS

Parameters:

scrollbarDisplayPolicy - SCROLLBARS_NEVER | SCROLLBARS_ASNEEDED | SCROLLBARS_ALWAYS

paint

public void paint(java.awt.Graphics g)

repaints the View.

Overrides:

paint in class java.awt.Canvas

itemAt

protected TreeNode itemAt(int y)

this should be private. having it protected is a present for dummy VM that doesn't know that an inner class can access private method of its parent class

update

public void update(java.awt.Graphics pg)

Overrides:

update in class java.awt.Canvas

insert

public void insert(TreeNode parent,
                   java.lang.Object item,
                   NodeHandler handler,
                   java.lang.String label,
                   java.awt.Image icon)

Inserts new node.

Parameters:

parent - the parent node.

remove

public void remove(TreeNode node)

Removes the specified node. This simply removes a node, without modifying its children if any. USE WITH CAUTION.

Parameters:

node - the node to remove

removeBranch

public void removeBranch(TreeNode node)

Removes the specified node and its children. NOTE: if two threads are doing adds and removes, this can lead to IndexOutOfBound exception. You will probably have to use locks to get rid of that problem

Parameters:

node - the node to remove

collapse

public void collapse(TreeNode item)

Contracts the representation of the specified node. removes all the children nodes of 'item'. It is caller's responsibility to call repaint() afterwards.

Parameters:

item - the node to contracts

setSelectionPolicy

public void setSelectionPolicy(int policy)

Sets the selection policy.

Parameters:

policy: - SINGLE or MULTIPLE

getSelectionPolicy

public int getSelectionPolicy()

Gets the selection policy.

select

public void select(TreeNode node)

Selects the specified node. Selects the given node. If selectionPolicy is SINGLE any previously selected node is unselected first. It is caller's responsibility to call repaint()

Parameters:

node - the node to select

unselect

public void unselect(TreeNode node)

Unselects the specified node. It is caller's responsibility to call repaint()

Parameters:

node - the node to unselect

unselectAll

public void unselectAll()

Unselects all selected items.

selection

public java.util.Enumeration selection()

Returns an Enumeraiton of selected items.

setVerticalScrollbar

public void setVerticalScrollbar(java.awt.Scrollbar a)

Sets 'a' as vertical Scrollbar. The Browser becomes an AdjustmentListener of this scrollbar.

setHorizontalScrollbar

public void setHorizontalScrollbar(java.awt.Scrollbar a)

Sets 'a' as horizontal Scrollbar. The Browser becomes an AdjustmentListener of this scrollbar.

adjustmentValueChanged

public void adjustmentValueChanged(java.awt.event.AdjustmentEvent evt)

Updates graphical appearance in response to a scroll.

Specified by:

adjustmentValueChanged in interface java.awt.event.AdjustmentListener

getParent

public TreeNode getParent(TreeNode child)

Returns the parent node of the specified node. If 'child' is a valid node belonging to the Tree and has a parent node, returns its parent. Returns null otherwise.

Parameters:

child - the child node you want to get its parent

getNode

public TreeNode getNode(java.lang.Object obj)

Gets the node associated to the specified object, or null if any.

Parameters:

obj - the object related to a node