JavaScript Reference

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Traversal API

Object

Description

Availability

NodeFilter

Specifies which nodes should be filtered when a document is traversed.

4.6 or later

NodeIterator

Enables navigation up and down through a flat representation of the document tree.

4.6 or later

TreeWalker

Enables navigate of the document tree or subtree.

4.6 or later

Object: NodeFilter

Availability

BlackBerry Device Software version 4.6 or later

The NodeFilter object is used to filter out nodes. If a NodeIterator or TreeWalker is given a NodeFilter, it applies the filter before it returns the next node. If the filter says to accept the node, the traversal object, either a NodeIterator or TreeWalker, returns it; otherwise, the traversal object looks for the next node and acts as if that the node that was rejected was not there.

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NodeFilter constants

Constants returned by NodeFilter.acceptNode().

Constant

Value type

Description

Support level

Availability

1

FILTER_ACCEPT

Accepts the node. This node will be returned with the results of a NodeIterator or TreeWalker object.

DOM 2 Traversal

4.6 or later

2

FILTER_REJECT

Rejects the node. This node will not be returned with the results of a NodeIterator or TreeWalker object. For TreeWalker objects, the children of this node are also excluded.

DOM 2 Traversal

4.6 or later

3

FILTER_SKIP

Skips the node. This node will not be returned with the results of a NodeIterator or TreeWalker object. Children of this node are still considered.

DOM 2 Traversal

4.6 or later

Constants for the NodeIterator.whatToShow and TreeWalker.whatToShow properties.

Constant

Value type

Description

Support level

Availability

0xFFFFFFFF

SHOW_ALL

Shows all nodes.

DOM 2 Traversal

4.6 or later

0x00000001

SHOW_ELEMENT

Shows Element nodes.

DOM 2 Traversal

4.6 or later

0x00000002

SHOW_ATTRIBUTE

Shows Attr nodes.

Because attributes are not the child of any other node, they never appear in the NodeIterator’s or TreeWalkers's logical view unless they are defined as the root of the object. If the respective node is not defined as the root, then SHOW_ATTRIBUTE has no meaning.

DOM 2 Traversal

4.6 or later

0x00000004

SHOW_TEXT

Shows Text nodes.

DOM 2 Traversal

4.6 or later

0x00000008

SHOW_CDATA_SECTION

Shows CDATASection nodes.

DOM 2 Traversal

4.6 or later

0x00000010

SHOW_ENTITY_REFERENCE

Shows EntityReference nodes.

DOM 2 Traversal

4.6 or later

0x00000020

SHOW _ENTITY

Shows Entity nodes.

Because entities are not the child of any other node, they never appear in the NodeIterator’s or TreeWalkers's logical view unless they are defined as the root of the object. If the respective node is not defined as the root, then SHOW_ENTITY has no meaning.

DOM 2 Traversal

4.6 or later

0x00000040

SHOW_PROCESSING_INSTRUCTION

Shows ProcessingInstruction nodes.

DOM 2 Traversal

4.6 or later

0x00000080

SHOW_COMMENT

Shows Comment nodes.

DOM 2 Traversal

4.6 or later

0x00000100

SHOW_DOCUMENT

Shows Document nodes.

DOM 2 Traversal

4.6 or later

0x00000200

SHOW_DOCUMENT_TYPE

Shows DocumentType nodes.

DOM 2 Traversal

4.6 or later

0x00000400

SHOW_DOCUMENT_FRAGMENT

Shows DocumentFragment nodes.

DOM 2 Traversal

4.6 or later

0x00000800

SHOW_NOTATION

Shows Notation nodes.

Because notations are not the child of any other node, they never appear in the NodeIterator’s or TreeWalkers's logical view unless they are defined as the root of the object. If the respective node is not defined as the root, then SHOW_NOTATION has no meaning.

DOM 2 Traversal

4.6 or later

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NodeFilter methods

Method name

Description

Support level

Availability

acceptNode()

Tests whether a specified node is visible in the logical view of a NodeIterator or TreeWalker. Returns a NodeFilter constant.

DOM 2 Traversal

4.6 or later

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Object: NodeIterator

Availability

BlackBerry Device Software version 4.6 or later

The NodeIterator object enables you to navigate up and down through a flat representation of the document tree. This object is similar to the TreeWalker objects, except that TreeWalker presents nodes in a tree-oriented view, rather than the list view presented by NodeIterator.

Create a NodeIterator using Document.createNodeIterator().

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NodeIterator properties

Property name

Type

Description

Status

Support level

Availability

expandEntityReferences

boolean

Returns whether or not the NodeIterator expands the entity references it encounters as it traverses the document.

read only

DOM 2 Traversal

4.6 or later

filter

NodeFilter

Returns the NodeFilter used to filter nodes for traversal.

read only

DOM 2 Traversal

4.6 or later

root

Node

Returns the Node at which the NodeIterator begins traversing the document.

read only

DOM 2 Traversal

4.6 or later

whatToShow

unsigned long

Returns which node types are presented by the NodeIterator, represented by one or more NodeFilter constants.

Multiple values may be specified using a bitwise OR.

read only

DOM 2 Traversal

4.6 or later

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NodeIterator methods

Method name

Description

Support level

Availability

detach()

Detaches the NodeIterator from the set which it iterated over.

DOM 2 Traversal

4.6 or later

nextNode()

Moves the NodeIterator to the next visible Node in the document order, relative to the current node.

DOM 2 Traversal

4.6 or later

previousNode()

Moves the NodeIterator to the previous visible Node in the document order, relative to the current node.

DOM 2 Traversal

4.6 or later

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Object: TreeWalker

Availability

BlackBerry Device Software version 4.6 or later

The TreeWalker object enables you to navigate the document tree or subtree. This object is similar to the NodeIterator objects, except that TreeWalker presents nodes in a tree-oriented view, rather than the list view presented by NodeIterator. This allows you to use TreeWalker to navigate directly to a parent or child, rather than simply up and down in the list using NodeIterator.

Create a TreeWalker using Document.createTreeWalker().

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TreeWalker properties

Property name

Type

Description

Status

Support level

Availability

currentNode

Node

Specifies the current position of the TreeWalker.

writable

DOM 2 Traversal

4.6 or later

expandEntityReferences

boolean

Returns whether or not the TreeWalker expands the entity references it encounters as it traverses the document.

read only

DOM 2 Traversal

4.6 or later

filter

NodeFilter

Returns the NodeFilter used to filter nodes for traversal.

read only

DOM 2 Traversal

4.6 or later

root

Node

Returns the Node at which the TreeWalker begins traversing the document.

read only

DOM 2 Traversal

4.6 or later

whatToShow

unsigned long

Returns which node types are presented by the TreeWalker, represented by one or more NodeFilter constants.

Multiple values may be specified using a bitwise OR.

read only

DOM 2 Traversal

4.6 or later

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TreeWalker methods

Method name

Description

Support level

Availability

firstChild()

Moves the TreeWalker to the first visible child of the current node.

DOM 2 Traversal

4.6 or later

lastChild()

Moves the TreeWalker to the last visible child of the current node.

DOM 2 Traversal

4.6 or later

nextNode()

Moves the TreeWalker to the next visible node in the document order, relative to the current node.

DOM 2 Traversal

4.6 or later

nextSibling()

Moves the TreeWalker to the next sibling of the current node.

DOM 2 Traversal

4.6 or later

parentNode()

Moves the TreeWalker to the closest visible ancestor node of the current node.

DOM 2 Traversal

4.6 or later

previousNode()

Moves the TreeWalker to the previous visible node in the document order, relative to the current node.

DOM 2 Traversal

4.6 or later

previousSibling()

Moves the TreeWalker to the previous sibling of the current node.

DOM 2 Traversal

4.6 or later

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