- Author:
- David Nickerson <nickerso@users.sourceforge.net>
- Date:
- 2009-07-16 02:00:03+12:00
- Desc:
- the starting point for the HH tutorial example
- Permanent Source URI:
- https://models.fieldml.org/workspace/a1/rawfile/f6a8f90307388eb4b040ee3566b84d88b59247f7/dojo-presentation/js/dojo/dojox/wire/XmlWire.js
dojo.provide("dojox.wire.XmlWire");
dojo.require("dojox.data.dom");
dojo.require("dojox.wire.Wire");
dojo.declare("dojox.wire.XmlWire", dojox.wire.Wire, {
// summary:
// A Wire for XML nodes or values (element, attribute and text)
// description:
// This class accesses XML nodes or value with a simplified XPath
// specified to 'path' property.
// The root object for this class must be an DOM document or element
// node.
// "@name" accesses to an attribute value of an element and "text()"
// accesses to a text value of an element.
// The hierarchy of the elements from the root node can be specified
// with slash-separated list, such as "a/b/@c", which specifies
// the value of an attribute named "c" of an element named "b" as
// a child of another element named "a" of a child of the root node.
_wireClass: "dojox.wire.XmlWire",
constructor: function(/*Object*/args){
// summary:
// Initialize properties
// description:
// 'args' is just mixed in with no further processing.
// args:
// Arguments to initialize properties
// path:
// A simplified XPath to an attribute, a text or elements
},
_getValue: function(/*Node*/object){
// summary:
// Return an attribute value, a text value or an array of elements
// description:
// This method first uses a root node passed in 'object' argument
// and 'path' property to identify an attribute, a text or
// elements.
// If 'path' starts with a slash (absolute), the first path
// segment is ignored assuming it point to the root node.
// (That is, "/a/b/@c" and "b/@c" against a root node access
// the same attribute value, assuming the root node is an element
// with a tag name, "a".)
// object:
// A root node
// returns:
// A value found, otherwise 'undefined'
if(!object || !this.path){
return object; //Node
}
var node = object;
var path = this.path;
if(path.charAt(0) == '/'){ // absolute
// skip the first expression (supposed to select the top node)
var i = path.indexOf('/', 1);
path = path.substring(i + 1);
}
var list = path.split('/');
var last = list.length - 1;
for(var i = 0; i < last; i++){
node = this._getChildNode(node, list[i]);
if(!node){
return undefined; //undefined
}
}
var value = this._getNodeValue(node, list[last]);
return value; //String||Array
},
_setValue: function(/*Node*/object, /*String*/value){
// summary:
// Set an attribute value or a child text value to an element
// description:
// This method first uses a root node passed in 'object' argument
// and 'path' property to identify an attribute, a text or
// elements.
// If an intermediate element does not exist, it creates
// an element of the tag name in the 'path' segment as a child
// node of the current node.
// Finally, 'value' argument is set to an attribute or a text
// (a child node) of the leaf element.
// object:
// A root node
// value:
// A value to set
if(!this.path){
return object; //Node
}
var node = object;
var doc = this._getDocument(node);
var path = this.path;
if(path.charAt(0) == '/'){ // absolute
var i = path.indexOf('/', 1);
if(!node){
var name = path.substring(1, i);
node = doc.createElement(name);
object = node; // to be returned as a new object
}
// skip the first expression (supposed to select the top node)
path = path.substring(i + 1);
}else{
if(!node){
return undefined; //undefined
}
}
var list = path.split('/');
var last = list.length - 1;
for(var i = 0; i < last; i++){
var child = this._getChildNode(node, list[i]);
if(!child){
child = doc.createElement(list[i]);
node.appendChild(child);
}
node = child;
}
this._setNodeValue(node, list[last], value);
return object; //Node
},
_getNodeValue: function(/*Node*/node, /*String*/exp){
// summary:
// Return an attribute value, a text value or an array of elements
// description:
// If 'exp' starts with '@', an attribute value of the specified
// attribute is returned.
// If 'exp' is "text()", a child text value is returned.
// Otherwise, an array of child elements, the tag name of which
// match 'exp', is returned.
// node:
// A node
// exp:
// An expression for attribute, text or elements
// returns:
// A value found, otherwise 'undefined'
var value = undefined;
if(exp.charAt(0) == '@'){
var attribute = exp.substring(1);
value = node.getAttribute(attribute);
}else if(exp == "text()"){
var text = node.firstChild;
if(text){
value = text.nodeValue;
}
}else{ // assume elements
value = [];
for(var i = 0; i < node.childNodes.length; i++){
var child = node.childNodes[i];
if(child.nodeType === 1 /* ELEMENT_NODE */ && child.nodeName == exp){
value.push(child);
}
}
}
return value; //String||Array
},
_setNodeValue: function(/*Node*/node, /*String*/exp, /*String*/value){
// summary:
// Set an attribute value or a child text value to an element
// description:
// If 'exp' starts with '@', 'value' is set to the specified
// attribute.
// If 'exp' is "text()", 'value' is set to a child text.
// node:
// A node
// exp:
// An expression for attribute or text
// value:
// A value to set
if(exp.charAt(0) == '@'){
var attribute = exp.substring(1);
if(value){
node.setAttribute(attribute, value);
}else{
node.removeAttribute(attribute);
}
}else if(exp == "text()"){
while(node.firstChild){
node.removeChild(node.firstChild);
}
if(value){
var text = this._getDocument(node).createTextNode(value);
node.appendChild(text);
}
}
// else not supported
},
_getChildNode: function(/*Node*/node, /*String*/name){
// summary:
// Return a child node
// description:
// A child element of the tag name specified with 'name' is
// returned.
// If 'name' ends with an array index, it is used to pick up
// the corresponding element from multiple child elements.
// node:
// A parent node
// name:
// A tag name
// returns:
// A child node
var index = 1;
var i1 = name.indexOf('[');
if(i1 >= 0){
var i2 = name.indexOf(']');
index = name.substring(i1 + 1, i2);
name = name.substring(0, i1);
}
var count = 1;
for(var i = 0; i < node.childNodes.length; i++){
var child = node.childNodes[i];
if(child.nodeType === 1 /* ELEMENT_NODE */ && child.nodeName == name){
if(count == index){
return child; //Node
}
count++;
}
}
return null; //null
},
_getDocument: function(/*Node*/node){
// summary:
// Return a DOM document
// description:
// If 'node' is specified, a DOM document of the node is returned.
// Otherwise, a DOM document is created.
// returns:
// A DOM document
if(node){
return (node.nodeType == 9 /* DOCUMENT_NODE */ ? node : node.ownerDocument); //Document
}else{
return dojox.data.dom.createDocument(); //Document
}
}
});
