Try this:
<!DOCTYPE html>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>Select</title>
<link rel="stylesheet" type="text/css" href="http://js.arcgis.com/3.7/js/dojo/dojo/resources/dojo.css" />
<link rel="stylesheet" href="http://js.arcgis.com/3.7/js/dojo/dijit/themes/claro/claro.css">
<link rel="stylesheet" href="http://js.arcgis.com/3.7/js/esri/css/esri.css">
<link rel="stylesheet" type="text/css" href="http://js.arcgis.com/3.7/js/dojo/dijit/themes/claro/document.css" />
<style>
html, body, .dijitBorderContainer {
width: 100%;
height: 100%;
margin: 0;
overflow:hidden;
}
</style>
</head>
<body class="claro">
<select id="distSelect" data-dojo-type="dijit/form/FilteringSelect"
data-dojo-props="title:'Find schools in selected district',maxHeight:200, size: 30, labelAttr:'label', searchAttr:'label',autoComplete:false,queryExpr:'*${0}*',placeHolder:'Pick a District'">
</select>
</body>
<script type="text/javascript">
var dojoConfig = {
async: true,
parseOnLoad:true
};
</script>
<script src="http://js.arcgis.com/3.7/"></script>
<script type="text/javascript">
require(["dojo/_base/declare", "dojo/ready", "dijit/registry", "dijit/form/Button", "dijit/form/FilteringSelect", "dojo/store/Memory"],
function (declare, ready, registry, Button, FilteringSelect, Memory) {
//fire when dojo is "ready"
ready(function () {
//create a distric list
var districtList = [
{ label: "District One", value: "Dist 1" },
{ label: "District Two", value: "Dist 2" },
{ label: "District Three", value: "Dist 3" },
{ label: "District Four", value: "Dist 4" }
];
//add a button
var button = new Button({ label: "Populate Select",
onClick: function () {
//get the filteringselect
var select = registry.byId("distSelect");
//set the select's store using the districtlist
select.set("store", new Memory({ data: districtList, idProperty: "value" }));
}
});
button.placeAt(document.body);
});
});
</script>
</html>