Package org.eclipse.zest.layouts.algorithms

Class TreeLayoutObserver

java.lang.Object

org.eclipse.zest.layouts.algorithms.TreeLayoutObserver

public class TreeLayoutObserver
extends Object

A helper class for layout algorithms that are based on tree structure. It keeps track of changes in observed layout context and stores current information about the tree structure - children of each node and several other parameters.

Since:

2.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	TreeLayoutObserver.TreeListener	A superclass for listeners that can be added to this observer to get notification whenever the tree structure changes.
static class	TreeLayoutObserver.TreeNode	Represents a node in a tree structure and stores all information related to it.
static class	TreeLayoutObserver.TreeNodeFactory	TreeLayoutObserver uses instance of this class to create instances of TreeLayoutObserver.TreeNode.

Constructor Summary

Constructors

Constructor	Description
TreeLayoutObserver(LayoutContext context, TreeLayoutObserver.TreeNodeFactory nodeFactory)	Creates a

Method Summary

Modifier and Type	Method	Description
void	addTreeListener(TreeLayoutObserver.TreeListener listener)	Adds a listener that will be informed about changes in tree structure.
TreeLayoutObserver.TreeNode	getSuperRoot()	Returns Super Root, that is an artificial node being a common parent for all nodes in observed tree structure.
TreeLayoutObserver.TreeNode	getTreeNode(NodeLayout node)	Returns a TreeLayoutObserver.TreeNode related to given node layout.
void	recomputeTree()	Recomputes all the information about the tree structure (the same effect as creating new TreeLayoutObserver).
void	removeTreeListener(TreeLayoutObserver.TreeListener listener)	Removes a listener from list of listener to be informed about changes in tree structure.
void	stop()	Stops this observer from listening to changes in observed layout context.

Methods inherited from class java.lang.Object

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

Constructor Details

TreeLayoutObserver

public TreeLayoutObserver(LayoutContext context,
 TreeLayoutObserver.TreeNodeFactory nodeFactory)

Creates a

Parameters:

context -

nodeFactory -

Method Details

recomputeTree

public void recomputeTree()

Recomputes all the information about the tree structure (the same effect as creating new TreeLayoutObserver).

stop

public void stop()

Stops this observer from listening to changes in observed layout context. After calling this method the information about tree structure can be updated only when recomputeTree() is called.

getSuperRoot

public TreeLayoutObserver.TreeNode getSuperRoot()

Returns Super Root, that is an artificial node being a common parent for all nodes in observed tree structure.

Returns:

Super Root

getTreeNode

public TreeLayoutObserver.TreeNode getTreeNode(NodeLayout node)

Returns a TreeLayoutObserver.TreeNode related to given node layout. If such a TreeNode doesn't exist, it's created.

Parameters:

node -

addTreeListener

public void addTreeListener(TreeLayoutObserver.TreeListener listener)

Adds a listener that will be informed about changes in tree structure.

Parameters:

listener - listener to add

removeTreeListener

public void removeTreeListener(TreeLayoutObserver.TreeListener listener)

Removes a listener from list of listener to be informed about changes in tree structure.

Parameters:

listener - listener to remove