Updated

2013-02-20 10:38:25 +01:00
parent 17c3936ab6
commit 5d14b9e2d4
1919 changed files with 559755 additions and 2588 deletions
--- a/master/examples/demo_LazyLoad.html
+++ b/master/examples/demo_LazyLoad.html
@@ -0,0 +1,66 @@
+<!--
+  This file is a simple loader for the Lazy Load demo of a Datastore.  In this
+  Example, a simple extension of ItemFileReadStore that can do rudimentary lazy-loading
+  of items into the store is used to showcase how Datastores can hide how data
+  is loaded from the widget.  As long as the widget implements to the Dojo.data API
+  spec, then it should be able to use most datastores as input sources for its
+  values.
+-->
+<html>
+<head>
+	<title>Demo of Lazy Loading Datastore</title>
+	<style type="text/css">
+
+		@import "../../../dijit/themes/tundra/tundra.css";
+		@import "../../../dojo/resources/dojo.css";
+		@import "../../../dijit/tests/css/dijitTests.css";
+	</style>
+
+	<script type="text/javascript" src="../../../dojo/dojo.js" djConfig="isDebug: true, parseOnLoad: true, usePlainJson: true"></script>
+	<script type="text/javascript">
+		dojo.require("dojo.parser");
+		dojo.require("dojox.data.demos.stores.LazyLoadJSIStore");
+		dojo.require("dijit.Tree");
+	</script>
+</head>
+
+<body class="tundra">
+	<h1>
+		DEMO:  Lazy Loading Datastore used by dijit.Tree
+	</h1>
+	<hr>
+	<h3>
+		Description:
+	</h3>
+	<p>
+		This simple demo shows how the dijit.Tree widget can work with a Datastore that does lazy-loading of values into the tree.  
+		In this demo, the Datastore is an extension of ItemFileReadStore that overrides the <i>isItemLoaded()</i> and <i>loadItem()</i> functions of
+		with ones that can detect 'stub' items and use the data in the stub item to load the real data for that item when it
+		is required.  In this demo, the real data is required when one of the tree nodes is expanded.
+	</p>
+	<p>
+		The key thing to note is that all the lazy-loading logic (how to locate the data from the backend and so forth) is encapsulated 
+		into the store functions.  The dijit.Tree widget only knows about and uses the dojo.data.Read API interfaces to call to the store to 
+		get items, test if child items are fully loaded or not, and to invoke the <i>loadItem()</i>  function on items that are not yet fully 
+		loaded but have been requested to be expanded into view.  It has no knowledge of how the store actually goes and gets the data.
+	</p>        
+
+	<blockquote>
+
+	<!--
+		The store instance used by this demo.
+	-->
+	<div dojoType="dojox.data.demos.stores.LazyLoadJSIStore" jsId="continentStore"
+		url="geography/root.json"></div>
+
+	<!-- 
+		Display the toplevel tree with items that have an attribute of 'type',
+		with value of 'contintent'
+	-->
+	<b>Continents</b>
+	<div dojoType="dijit.Tree" id=tree label="Continents" store="continentStore" query="{type:'continent'}"
+		labelAttr="name" typeAttr="type"></div>
+	</blockquote>
+
+</body>
+</html>