Here's a page with several scenarios:<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<meta http-equiv="X-UA-Compatible" content="IE=7,IE=9" />
<!--The viewport meta tag is used to improve the presentation and behavior of the samples
on iOS devices-->
<meta name="viewport" content="initial-scale=1, maximum-scale=1,user-scalable=no"/>
<title>
</title>
<link rel="stylesheet" type="text/css" href="http://serverapi.arcgisonline.com/jsapi/arcgis/3.0/js/dojo/dijit/themes/claro/claro.css">
<style type="text/css">
html, body { height: 100%; width: 100%; margin: 0; padding: 0; }
#map{
padding:0;
}
</style>
<script type="text/javascript">
var djConfig = {
parseOnLoad: true
};
</script>
<script type="text/javascript" src="http://serverapi.arcgisonline.com/jsapi/arcgis/?v=3.0"></script>
<script type="text/javascript">
dojo.require("dijit.dijit"); // optimize: load dijit layer
dojo.require("dijit.layout.BorderContainer");
dojo.require("dijit.layout.ContentPane");
dojo.require("esri.map");
//dojo.require("esri.virtualearth.VETiledLayer");
dojo.require("dijit.TitlePane");
dojo.require("esri.dijit.BasemapGallery");
dojo.require("esri.arcgis.utils");
//var map = null;
function init() {
var initExtent = new esri.geometry.Extent({ "xmin": -11727455, "ymin": 4861652, "xmax": -11706340, "ymax": 4871512, "spatialReference": { "wkid": 102100} });
var _map = new esri.Map("map", { extent: initExtent });
var initBasemap = new esri.layers.ArcGISTiledMapServiceLayer("http://server.arcgisonline.com/ArcGIS/rest/services/World_Topo_Map/MapServer");
_map.addLayer(initBasemap);
//add bmg to declarative contentpane html (existing)
var basemapGallery1 = new esri.dijit.BasemapGallery({
showArcGISBasemaps: true,
map: _map
}, "Div4");
basemapGallery1.startup();
//Programmatic 1 - will produce ID registry error
//add bmg to declarative titlepane html (existing)
// var basemapGallery2 = new esri.dijit.BasemapGallery({
// showArcGISBasemaps: true,
// map: _map
// }, "Div1");
// basemapGallery2.startup();
//Programmatic 2 - will produce empty
//add bmg to programmatic contentpane
var _tp1 = new dijit.TitlePane({title:"Programmatic 2"});
var _c1 = new dijit.layout.ContentPane({id:"c1",style:"background-color:lightblue;"});
var basemapGallery3 = new esri.dijit.BasemapGallery({
showArcGISBasemaps: true,
map: _map
}, "c1");
basemapGallery3.startup();
_tp1.setContent(_c1);
_tp1.placeAt(dijit.byId("leftside").containerNode);
//Programmatic 3 - will produce ID registry error
//add bmg to programmatic contentpane
// var _tp2 = new dijit.TitlePane({ title: "Programmatic 3" });
// var basemapGallery4 = new esri.dijit.BasemapGallery({
// showArcGISBasemaps: true,
// map: _map
// }, _tp2);
// basemapGallery4.startup();
// _tp2.placeAt(dijit.byId("leftside").containerNode);
//Programmatic 4 - will produce empty
//add bmg to programmatic contentpane
var _tp3 = new dijit.TitlePane({ title: "Programmatic 4" });
_tp3.placeAt(dijit.byId("leftside").containerNode);
var basemapGallery5 = new esri.dijit.BasemapGallery({
showArcGISBasemaps: true,
map: _map
}, _tp3.srcNodeRef);
basemapGallery5.startup();
//Programmatic 5 - will produce empty "flowcontainer"
//add bmg to programmatic contentpane
var _tp4 = new dijit.TitlePane({ title: "Programmatic 5" });
_tp4.placeAt(dijit.byId("leftside").containerNode);
var basemapGallery6 = new esri.dijit.BasemapGallery({
showArcGISBasemaps: true,
map: _map
});
basemapGallery6.startup();
_tp4.setContent(basemapGallery6);
//resize the map when the browser resizes
dojo.connect(dijit.byId('map'), 'resize', _map, _map.resize);
}
//show map on load
dojo.addOnLoad(init);
</script>
</head>
<body class="claro">
<div dojotype="dijit.layout.BorderContainer" design="sidebar" gutters="false" style="width:100%;height:100%;margin:0;">
<div id="leftside" dojotype="dijit.layout.ContentPane" region="left" style="width:200px;border:1px solid #000;padding:0;">
<div dojoType="dijit.TitlePane" id="Div3" title="Declarative Basemap" closable="false" open="false">
<div id="Div4"></div>
</div>
<div dojoType="dijit.TitlePane" id="Div1" title="Programmatic 1 Basemap" closable="false" open="false">
</div>
</div>
<div id="map" dojotype="dijit.layout.ContentPane" region="center" style="border:1px solid #000;padding:0;">
</div>
</div>
</body>
</html>
