[moved] Asynchronously map API load issue

[zonken]

Hello,
when following coding of my Application

var mapElement = document.getElementById("myID");
map = new nokia.maps.map.Display(mapElement, {
       components : [  new nokia.maps.map.component.Behavior(),
	        	new nokia.maps.map.component.ZoomBar(),
			new nokia.maps.map.component.Overview(),
			new nokia.maps.map.component.TypeSelector(),
			new nokia.maps.map.component.ScaleBar() ],
	// initial center and zoom level of the map
	center : [ 52.51, 13.4 ],
	zoomLevel : 10
	});

is called I get an error "Uncaught TypeError: Cannot read property 'Display' of undefined ".
I only get this error, when I try to load the API on runtime:

	var script = document.createElement("script");
	script.type = "text/javascript";
	script.charset="utf-8";
	script.async = true;
	script.onload = myCallback;
	script.src = "http://api.maps.nokia.com/2.2.3/jsl.js?with=all";
	document.head.appendChild(script);

myCallback is reached. But map is undefined. I also tried to work with the Features.load method to enforce another call back before I start accessing the map object but here I never got an callback:

nokia.Features.load({"map": "auto"}, function(){alert("123");},  function(){alert("321");});

When I replace this with a static script tag in HTML head, everything works fine:

<script src="http://api.maps.nokia.com/2.2.3/jsl.js?with=all"
	type="text/javascript">
</script>

But I prefer to do this on the fly. Any idea what I made wrong?

[jasfox]

It looks like a flaw in the design of the feature loader to me. At the moment the feature loader is usually used to add additional functionality (e.g. routing) after the base JavaScript library has already been loaded.

For example load the basic library without the with parameter

<script src="http://api.maps.nokia.com/2.2.3/jsl.js" type="text/javascript">
</script>

and then use Features to add routing or places or whatever, does work. However it doesn't look like bootstrapping the complete library from the DOM is available at the moment.

I know asynchronous loading is an advanced use case, but it seems reasonable to support it. I've had a discussion with the development team, and I'm lobbying to get the Feature documentation upgraded and the design flaw fixed in the next release cycle.
Until this is implemented you'll have to stick with loading the basic library in the <SCRIPT> tag, I'm afraid.

[zonken]

Hi Jason,
thanks for the fast reply. It is good to know and I can stop spending time in looking what I made wrong.
If there will be a async Feature in future; do you have an idea about the timeline, when it would be available?
I Wish you a nice weekend.
Regards,
Rico

[jasfox]

Hi Zonken,

I wouldn't like to commit to timeline, as the setting of priorities is not my call. Certainly the development team recognise the need for this and hope to get a fix out sooner rather than later. A proper mechanism for following bug fixes/feature requests is one of the items on the internal to-do list (DEVPRES-10), so in the mean time the best thing to do is to raise and follow any issues here.

Regards,

Jason.

[jasfox]

Asynchronous Loading support has been introduced in version 2.2.4 of the Maps API for Javascript:

A worked example can be found in the wiki