Solution for ActionSupport on Lookups for a Visualforce Page

Hello there, There are two reasons why you are on this page, one is that you like to go through Force.com blogs and gain as much knowledge as you can. Its a good thing, only you won't gain any knowledge reading the blogs but by digging. Two, you are highly frustrated and have Googled extensively for keywords 'ActionSupport', 'Lookup' and 'Visualforce' for many hours and before that were struggling with ActionSupport, onblur, onChange and other events.

If you are here for second reason, we both sail in the same ship and even though I may sound like a telemarketer who is keen on wasting your time, I however, would like to inform you that I am sympathetic towards you. After having struggling to get this thing work on a Lookup for a long time, I decided to embark on the journey that took me back in time even before Salesforce.com existed. I went to the very depths of DOM and source code. Right to the birth place... ok not really, but I am just back from Star Wars Movie Marathon and still a bit woozie.

So anyways yes, the solution.

The code:
This is how your code will be looking right now:

<apex:pageBlockSection >

<apex:inputField value="{!someLookup__c}" >

<apex:actionSupport event="onChange" action="{!SomeAction}" rerender="thePageBlock" status="theStatus"/>         

</apex:inputField>

</apex:pageBlockSection>

<apex:pageBlock id="thePageBlock">

      //Something cool here.

</apex:pageBlock>  

So we need to do a bit of tweaking for this code and use the Big brother of ActionSupport, change the code to this

Corrected Code:

<apex:pageBlockSection >

        <apex:inputField value="{!someLookup__c}" onChange="someJs()"/>



<apex:actionFunction name="someJs" action="{!SomeAction}" rerender="thePageBlock" status="theStatus"/>    

         </apex:pageBlockSection>

<apex:pageBlock id="thePageBlock">

      Something cool here.

</apex:pageBlock>  

Obviously this is a workaround for the problem. There are some questions in the community as is this a bug in Salesforce? I don't think so.

Basically this has something to do with very primitive that is, native HTML. See lookup may be easy to build and render, but deep down it converts itself into a HTML component. In HTML it is split into two different components, one input field and another hidden field. As this is a complex rendering in itself, adding another event to it using actionSupport would be much tedious task.

If they do, obviously, its awesome.

Whats more?

Instead of actionFuction we can also call a native javascript code for the same. Well I changed my mood from aaarggh to Wuuu huuu.

Hope it makes you the happy as well. 

Toodles for now,

Siddhesh