opmlstore.js

这是一个ajax的例子大家好好的看看就是一个鱼眼的效果

if(!dojo._hasResource["dojox.data.OpmlStore"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
dojo._hasResource["dojox.data.OpmlStore"] = true;
dojo.provide("dojox.data.OpmlStore");

dojo.require("dojo.data.util.filter");
dojo.require("dojo.data.util.simpleFetch");

dojo.declare("dojox.data.OpmlStore", null, {
	/* summary:
	 *   The OpmlStore implements the dojo.data.api.Read API.  
	 */
	 
	/* examples:
	 *   var opmlStore = new dojo.data.OpmlStore({url:"geography.xml"});
	 *   var opmlStore = new dojo.data.OpmlStore({url:"http://example.com/geography.xml"});
	 */
	constructor: function(/* Object */ keywordParameters){
		// summary: constructor
		// keywordParameters: {url: String, label: String}  Where label is optional and configures what should be used as the return from getLabel()
		this._xmlData = null;
		this._arrayOfTopLevelItems = [];
		this._arrayOfAllItems = [];
		this._metadataNodes = null;
		this._loadFinished = false;
		this.url = keywordParameters.url;
		this._opmlData = keywordParameters.data;  // XML DOM Document
		if(keywordParameters.label){
			this.label = keywordParameters.label;
		}
		this._loadInProgress = false;	//Got to track the initial load to prevent duelling loads of the dataset.
		this._queuedFetches = [];
		this._identityMap = {};
		this._identCount = 0;
		this._idProp = "_I";
	},

	label: "text",

	url: "",

	_assertIsItem: function(/* item */ item){
		if(!this.isItem(item)){ 
			throw new Error("dojo.data.OpmlStore: a function was passed an item argument that was not an item");
		}
	},
	
	_assertIsAttribute: function(/* item || String */ attribute){
		//	summary:
		//      This function tests whether the item passed in is indeed a valid 'attribute' like type for the store.
		//	attribute: 
		//		The attribute to test for being contained by the store.
		if(!dojo.isString(attribute)){
			throw new Error("dojox.data.OpmlStore: a function was passed an attribute argument that was not an attribute object nor an attribute name string");
		}
	},
	
	_removeChildNodesThatAreNotElementNodes: function(/* node */ node, /* boolean */ recursive){
		var childNodes = node.childNodes;
		if(childNodes.length === 0){
			return;
		}
		var nodesToRemove = [];
		var i, childNode;
		for(i = 0; i < childNodes.length; ++i){
			childNode = childNodes[i];
			if(childNode.nodeType != 1){ 
				nodesToRemove.push(childNode); 
			}
		}
		for(i = 0; i < nodesToRemove.length; ++i){
			childNode = nodesToRemove[i];
			node.removeChild(childNode);
		}
		if(recursive){
			for(i = 0; i < childNodes.length; ++i){
				childNode = childNodes[i];
				this._removeChildNodesThatAreNotElementNodes(childNode, recursive);
			}
		}
	},
	
	_processRawXmlTree: function(/* xmlDoc */ rawXmlTree){
		this._loadFinished = true;
		this._xmlData = rawXmlTree;
		var headNodes = rawXmlTree.getElementsByTagName('head');
		var headNode = headNodes[0];
		if(headNode){
			this._removeChildNodesThatAreNotElementNodes(headNode);
			this._metadataNodes = headNode.childNodes;
		}
		var bodyNodes = rawXmlTree.getElementsByTagName('body');
		var bodyNode = bodyNodes[0];
		if(bodyNode){
			this._removeChildNodesThatAreNotElementNodes(bodyNode, true);
			
			var bodyChildNodes = bodyNodes[0].childNodes;
			for(var i = 0; i < bodyChildNodes.length; ++i){
				var node = bodyChildNodes[i];
				if(node.tagName == 'outline'){
					this._identityMap[this._identCount] = node;
					this._identCount++;
					this._arrayOfTopLevelItems.push(node);
					this._arrayOfAllItems.push(node);
					this._checkChildNodes(node);
				}
			}
		}
	},

	_checkChildNodes: function(node /*Node*/){
		//	summary:
		//		Internal function to recurse over all child nodes from the store and add them
		//		As non-toplevel items
		//	description:
		//		Internal function to recurse over all child nodes from the store and add them
		//		As non-toplevel items
		//
		//	node:
		//		The child node to walk.
		if(node.firstChild){
			for(var i = 0; i < node.childNodes.length; i++){
				var child = node.childNodes[i];
				if(child.tagName == 'outline'){
					this._identityMap[this._identCount] = child;
					this._identCount++;
					this._arrayOfAllItems.push(child);
					this._checkChildNodes(child);
				}
			}
		}
	},

	_getItemsArray: function(/*object?*/queryOptions){
		//	summary: 
		//		Internal function to determine which list of items to search over.
		//	queryOptions: The query options parameter, if any.
		if(queryOptions && queryOptions.deep) {
			return this._arrayOfAllItems; 
		}
		return this._arrayOfTopLevelItems;
	},

/***************************************
     dojo.data.api.Read API
***************************************/
	getValue: function( /* item */ item,
						/* attribute || attribute-name-string */ attribute,
						/* value? */ defaultValue){
		//	summary: 
		//      See dojo.data.api.Read.getValue()
		this._assertIsItem(item);
		this._assertIsAttribute(attribute);
		if(attribute == 'children'){
			return (item.firstChild || defaultValue); //Object
		} else {
			var value = item.getAttribute(attribute);
			return (value !== undefined) ? value : defaultValue; //Object
		}
	},
	
	getValues: function(/* item */ item,
						/* attribute || attribute-name-string */ attribute){
		//	summary: 
		//		See dojo.data.api.Read.getValues()
		this._assertIsItem(item);
		this._assertIsAttribute(attribute);
		var array = [];
		if(attribute == 'children'){
			for(var i = 0; i < item.childNodes.length; ++i){
				array.push(item.childNodes[i]);
			}
		} else if(item.getAttribute(attribute) !== null){
				array.push(item.getAttribute(attribute));
		}
		return array; // Array
	},
	
	getAttributes: function(/* item */ item){
		//	summary: 
		//		See dojo.data.api.Read.getAttributes()
		this._assertIsItem(item);
		var attributes = [];
		var xmlNode = item;
		var xmlAttributes = xmlNode.attributes;
		for(var i = 0; i < xmlAttributes.length; ++i){
			var xmlAttribute = xmlAttributes.item(i);
			attributes.push(xmlAttribute.nodeName);
		}
		if(xmlNode.childNodes.length > 0){
			attributes.push('children');
		}
		return attributes; //Array
	},
	
	hasAttribute: function( /* item */ item,
							/* attribute || attribute-name-string */ attribute){
		//	summary: 
		//		See dojo.data.api.Read.hasAttribute()
		return (this.getValues(item, attribute).length > 0); //Boolean
	},
	
	containsValue: function(/* item */ item, 
							/* attribute || attribute-name-string */ attribute, 
							/* anything */ value){
		//	summary: 
		//		See dojo.data.api.Read.containsValue()
		var regexp = undefined;
		if(typeof value === "string"){
		   regexp = dojo.data.util.filter.patternToRegExp(value, false);
		}
		return this._containsValue(item, attribute, value, regexp); //boolean.
	},

	_containsValue: function(	/* item */ item, 
								/* attribute || attribute-name-string */ attribute, 
								/* anything */ value,
								/* RegExp?*/ regexp){
		//	summary: 
		//		Internal function for looking at the values contained by the item.
		//	description: 
		//		Internal function for looking at the values contained by the item.  This 
		//		function allows for denoting if the comparison should be case sensitive for
		//		strings or not (for handling filtering cases where string case should not matter)
		//	
		//	item:
		//		The data item to examine for attribute values.
		//	attribute:
		//		The attribute to inspect.
		//	value:	
		//		The value to match.
		//	regexp:
		//		Optional regular expression generated off value if value was of string type to handle wildcarding.
		//		If present and attribute values are string, then it can be used for comparison instead of 'value'
		var values = this.getValues(item, attribute);
		for(var i = 0; i < values.length; ++i){
			var possibleValue = values[i];
			if(typeof possibleValue === "string" && regexp){
				return (possibleValue.match(regexp) !== null);
			}else{
				//Non-string matching.
				if(value === possibleValue){
					return true; // Boolean
				}
			}
		}
		return false; // Boolean
	},
			
	isItem: function(/* anything */ something){
		//	summary: 
		//		See dojo.data.api.Read.isItem()
		//	description:
		//		Four things are verified to ensure that "something" is an item:
		//		something can not be null, the nodeType must be an XML Element,
		//		the tagName must be "outline", and the node must be a member of
		//		XML document for this datastore. 
		return (something && 
				something.nodeType == 1 &&