DOMTreeWalker Class Reference

DOMTreeWalker objects are used to navigate a document tree or subtree using the view of the document defined by their whatToShow flags and filter (if any). More...

List of all members.

Public Member Functions

Destructor
virtual ~DOMTreeWalker ()
 Destructor.
Functions introduced in DOM Level 2
virtual DOMNodegetRoot ()=0
 The root node of the DOMTreeWalker, as specified when it was created.
virtual unsigned long getWhatToShow ()=0
 This attribute determines which node types are presented via the DOMTreeWalker.
virtual DOMNodeFiltergetFilter ()=0
 Return The filter used to screen nodes.
virtual bool getExpandEntityReferences ()=0
 The value of this flag determines whether the children of entity reference nodes are visible to the DOMTreeWalker.
virtual DOMNodegetCurrentNode ()=0
 Return the node at which the DOMTreeWalker is currently positioned.
virtual DOMNodeparentNode ()=0
 Moves to and returns the closest visible ancestor node of the current node.
virtual DOMNodefirstChild ()=0
 Moves the DOMTreeWalker to the first visible child of the current node, and returns the new node.
virtual DOMNodelastChild ()=0
 Moves the DOMTreeWalker to the last visible child of the current node, and returns the new node.
virtual DOMNodepreviousSibling ()=0
 Moves the DOMTreeWalker to the previous sibling of the current node, and returns the new node.
virtual DOMNodenextSibling ()=0
 Moves the DOMTreeWalker to the next sibling of the current node, and returns the new node.
virtual DOMNodepreviousNode ()=0
 Moves the DOMTreeWalker to the previous visible node in document order relative to the current node, and returns the new node.
virtual DOMNodenextNode ()=0
 Moves the DOMTreeWalker to the next visible node in document order relative to the current node, and returns the new node.
virtual void setCurrentNode (DOMNode *currentNode)=0
 The node at which the DOMTreeWalker is currently positioned.
Non-standard Extension
virtual void release ()=0
 Called to indicate that this TreeWalker is no longer in use and that the implementation may relinquish any resources associated with it.

Protected Member Functions

Hidden constructors
 DOMTreeWalker ()
 DOMTreeWalker (const DOMTreeWalker &)


Detailed Description

DOMTreeWalker objects are used to navigate a document tree or subtree using the view of the document defined by their whatToShow flags and filter (if any).

Any function which performs navigation using a DOMTreeWalker will automatically support any view defined by a DOMTreeWalker.

Omitting nodes from the logical view of a subtree can result in a structure that is substantially different from the same subtree in the complete, unfiltered document. Nodes that are siblings in the DOMTreeWalker view may be children of different, widely separated nodes in the original view. For instance, consider a DOMNodeFilter that skips all nodes except for DOMText nodes and the root node of a document. In the logical view that results, all text nodes will be siblings and appear as direct children of the root node, no matter how deeply nested the structure of the original document.

See also the Document Object Model (DOM) Level 2 Traversal and Range Specification.

Since:
DOM Level 2

Constructor & Destructor Documentation

DOMTreeWalker::DOMTreeWalker (  )  [protected]

DOMTreeWalker::DOMTreeWalker ( const DOMTreeWalker  )  [protected]

virtual DOMTreeWalker::~DOMTreeWalker (  )  [virtual]

Destructor.


Member Function Documentation

virtual DOMNode* DOMTreeWalker::getRoot (  )  [pure virtual]

The root node of the DOMTreeWalker, as specified when it was created.

Since:
DOM Level 2

virtual unsigned long DOMTreeWalker::getWhatToShow (  )  [pure virtual]

This attribute determines which node types are presented via the DOMTreeWalker.

The available set of constants is defined in the DOMNodeFilter interface. Nodes not accepted by whatToShow will be skipped, but their children may still be considered. Note that this skip takes precedence over the filter, if any.

Since:
DOM Level 2

virtual DOMNodeFilter* DOMTreeWalker::getFilter (  )  [pure virtual]

Return The filter used to screen nodes.

Since:
DOM Level 2

virtual bool DOMTreeWalker::getExpandEntityReferences (  )  [pure virtual]

The value of this flag determines whether the children of entity reference nodes are visible to the DOMTreeWalker.

If false, these children and their descendants will be rejected. Note that this rejection takes precedence over whatToShow and the filter, if any.
To produce a view of the document that has entity references expanded and does not expose the entity reference node itself, use the whatToShow flags to hide the entity reference node and set expandEntityReferences to true when creating the DOMTreeWalker. To produce a view of the document that has entity reference nodes but no entity expansion, use the whatToShow flags to show the entity reference node and set expandEntityReferences to false.

Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::getCurrentNode (  )  [pure virtual]

Return the node at which the DOMTreeWalker is currently positioned.

Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::parentNode (  )  [pure virtual]

Moves to and returns the closest visible ancestor node of the current node.

If the search for parentNode attempts to step upward from the DOMTreeWalker's root node, or if it fails to find a visible ancestor node, this method retains the current position and returns null.

Returns:
The new parent node, or null if the current node has no parent in the DOMTreeWalker's logical view.
Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::firstChild (  )  [pure virtual]

Moves the DOMTreeWalker to the first visible child of the current node, and returns the new node.

If the current node has no visible children, returns null, and retains the current node.

Returns:
The new node, or null if the current node has no visible children in the DOMTreeWalker's logical view.
Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::lastChild (  )  [pure virtual]

Moves the DOMTreeWalker to the last visible child of the current node, and returns the new node.

If the current node has no visible children, returns null, and retains the current node.

Returns:
The new node, or null if the current node has no children in the DOMTreeWalker's logical view.
Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::previousSibling (  )  [pure virtual]

Moves the DOMTreeWalker to the previous sibling of the current node, and returns the new node.

If the current node has no visible previous sibling, returns null, and retains the current node.

Returns:
The new node, or null if the current node has no previous sibling. in the DOMTreeWalker's logical view.
Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::nextSibling (  )  [pure virtual]

Moves the DOMTreeWalker to the next sibling of the current node, and returns the new node.

If the current node has no visible next sibling, returns null, and retains the current node.

Returns:
The new node, or null if the current node has no next sibling. in the DOMTreeWalker's logical view.
Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::previousNode (  )  [pure virtual]

Moves the DOMTreeWalker to the previous visible node in document order relative to the current node, and returns the new node.

If the current node has no previous node, or if the search for previousNode attempts to step upward from the DOMTreeWalker's root node, returns null, and retains the current node.

Returns:
The new node, or null if the current node has no previous node in the DOMTreeWalker's logical view.
Since:
DOM Level 2

virtual DOMNode* DOMTreeWalker::nextNode (  )  [pure virtual]

Moves the DOMTreeWalker to the next visible node in document order relative to the current node, and returns the new node.

If the current node has no next node, or if the search for nextNode attempts to step upward from the DOMTreeWalker's root node, returns null, and retains the current node.

Returns:
The new node, or null if the current node has no next node in the DOMTreeWalker's logical view.
Since:
DOM Level 2

virtual void DOMTreeWalker::setCurrentNode ( DOMNode currentNode  )  [pure virtual]

The node at which the DOMTreeWalker is currently positioned.


Alterations to the DOM tree may cause the current node to no longer be accepted by the DOMTreeWalker's associated filter. currentNode may also be explicitly set to any node, whether or not it is within the subtree specified by the root node or would be accepted by the filter and whatToShow flags. Further traversal occurs relative to currentNode even if it is not part of the current view, by applying the filters in the requested direction; if no traversal is possible, currentNode is not changed.

Exceptions:
DOMException NOT_SUPPORTED_ERR: Raised if an attempt is made to set currentNode to null.
Since:
DOM Level 2

virtual void DOMTreeWalker::release (  )  [pure virtual]

Called to indicate that this TreeWalker is no longer in use and that the implementation may relinquish any resources associated with it.

Access to a released object will lead to unexpected result.


The documentation for this class was generated from the following file:
Generated on Thu Feb 19 11:35:45 2009 for Xerces-C++ by  doxygen 1.5.4