New feature: basic Ajax suggestion for tags and implementation of Dojo toolkit

git-svn-id: https://semanticscuttle.svn.sourceforge.net/svnroot/semanticscuttle/trunk@151 b3834d28-1941-0410-a4f8-b48e95affb8f

1 files changed, 142 insertions, 0 deletions

diff --git a/includes/js/dojox/data/demos/stores/LazyLoadJSIStore.js b/includes/js/dojox/data/demos/stores/LazyLoadJSIStore.js
new file mode 100644
index 0000000..e7acff7
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+++ b/includes/js/dojox/data/demos/stores/LazyLoadJSIStore.js
@@ -0,0 +1,142 @@
+if(!dojo._hasResource["dojox.data.demos.stores.LazyLoadJSIStore"]){ //_hasResource checks added by build. Do not use _hasResource directly in your code.
+dojo._hasResource["dojox.data.demos.stores.LazyLoadJSIStore"] = true;
+dojo.provide("dojox.data.demos.stores.LazyLoadJSIStore");
+dojo.require("dojo.data.ItemFileReadStore");
+
+dojo.declare("dojox.data.demos.stores.LazyLoadJSIStore", dojo.data.ItemFileReadStore, {
+	constructor: function(/* object */ keywordParameters){
+		// LazyLoadJSIStore extends ItemFileReadStore to implement an 
+		// example of lazy-loading/faulting in items on-demand.
+		// Note this is certianly not a perfect implementation, it is 
+		// an example.
+	},
+	
+	isItemLoaded: function(/*object*/ item) {
+		//	summary:
+		//		Overload of the isItemLoaded function to look for items of type 'stub', which indicate
+		//		the data hasn't been loaded in yet.
+		//
+		//	item:
+		//		The item to examine.
+		
+		//For this store, if it has the value of stub for its type attribute, 
+		//then the item basn't been fully loaded yet.  It's just a placeholder.
+		if(this.getValue(item, "type") === "stub"){
+			return false;
+		}
+		return true;
+	},
+		
+	loadItem: function(keywordArgs){
+		//	summary:
+		//		Overload of the loadItem function to fault in items.  This assumes the data for an item is laid out
+		//		in a RESTful sort of pattern name0/name1/data.json and so on and uses that to load the data.
+		//		It will also detect stub items in the newly loaded item and insert the stubs into the ItemFileReadStore
+		//		list so they can also be loaded in on-demand.
+		//
+		//	item:
+		//		The item to examine.
+
+		var item = keywordArgs.item;
+		this._assertIsItem(item);
+
+		//Build the path to the data.json for this item
+		//The path consists of where its parent was loaded from 
+		//plus the item name.
+		var itemName = this.getValue(item, "name");
+		var parent   = this.getValue(item, "parent");
+		var dataUrl  = "";
+		if (parent){
+			dataUrl += (parent + "/");
+		}
+
+		//For this store, all child input data is loaded from a url that ends with data.json
+		dataUrl += itemName + "/data.json";
+
+		//Need a reference to the store to call back to its structures.
+		var self = this;
+
+		// Callback for handling a successful load.
+		var gotData = function(data){
+			//Now we need to modify the existing item a bit to take it out of stub state
+			//Since we extend the store and have knowledge of the internal
+			//structure, this can be done here.  Now, is we extended
+			//a write store, we could call the write APIs to do this too
+			//But for a simple demo the diretc modification in the store function
+			//is sufficient.
+
+			//Clear off the stub indicators.
+			delete item.type;
+			delete item.parent;
+
+			//Set up the loaded values in the format ItemFileReadStore uses for attributes.
+			for (i in data) {
+				if (dojo.isArray(data[i])) {
+					item[i] = data[i];
+				}else{
+					item[i] = [data[i]];
+				}
+			}
+
+			//Reset the item in the reference.
+			self._arrayOfAllItems[item[self._itemNumPropName]] = item;
+
+			//Scan the new values in the item for extra stub items we need to 
+			//add to the items array of the store so they can be lazy-loaded later...
+			var attributes = self.getAttributes(item);
+			for(i in attributes){
+				var values = self.getValues(item, attributes[i]);
+				for (var j = 0; j < values.length; j++) {
+					var value = values[j];
+					
+					if(typeof value === "object"){
+						if(value["stub"] ){
+							//We have a stub reference here, we need to create the stub item
+							var stub = {
+								type: ["stub"],
+								name: [value["stub"]],	//
+								parent: [itemName]		//The child stub item is parented by this item name...
+							};
+							if (parent) {
+								//Add in any parents to your parent so URL construstruction is accurate.
+								stub.parent[0] = parent + "/" + stub.parent[0]; 
+							}
+							//Finalize the addition of the new stub item into the ItemFileReadStore list.
+							self._arrayOfAllItems.push(stub);
+							stub[self._storeRefPropName] = self;
+							stub[self._itemNumPropName] = (self._arrayOfAllItems.length - 1); //Last one pushed in should be the item
+							values[j] = stub; //Set the stub item back in its place and replace the stub notation.
+						}
+					}
+				}
+			}
+
+			//Done processing!  Call the onItem, if any.
+			if(keywordArgs.onItem){
+				var scope = keywordArgs.scope ? keywordArgs.scope : dojo.global;
+				keywordArgs.onItem.call(scope, item);
+			}
+		};
+
+		//Callback for any errors that occur during load.
+		var gotError = function(error){
+			//Call the onComplete, if any
+			if(keywordArgs.onError){
+				var scope = keywordArgs.scope ? keywordArgs.scope : dojo.global;
+				keywordArgs.onError.call(scope, error);
+			}
+		};
+
+		//Fire the get and pass the proper callbacks to the deferred.
+		var xhrArgs = {
+			url: dataUrl,
+			handleAs: "json-comment-optional"
+		};
+		var d = dojo.xhrGet(xhrArgs);
+		d.addCallback(gotData);
+		d.addErrback(gotError);
+	}
+});
+
+
+}