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+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);
+ }
+});
+
+
+}