
Recently, I was bitten by a IE bug.

On one of the page I am working on, there are two radio buttons. The requirement is to auto-submit the page when the user clicks on one of the radio button. Apart from the radio buttons, there is an `<input type="submit" onclick="someJavaScript(param1, param2);" />` element too, but this is hidden as per the UI requirements.

So, in order to do auto-submit of the page on click of radio button, my first approach was to, bind an event handler to the radio button and programmatically click on the submit button. Below is the source code to do this:

```javascript
(function(){
  $('#radioBtnId').on('click', function(event){
    $('#submitBtnId').click();
  });
}());
```

Well, a simple & straight forward code, isn't it!? But, IE8 doesn't think so (surprise!).

While the above code works well in Chrome / Firefox / IE9, it is failing in IE8. On investigating, I came to know that IE8 does not trigger events for the hidden elements.

So, IE is just being an IE here and I had to look for other ways to implement the auto-submit.

Luckily, in my case, the submit button need not to be clicked. It is enough if I could just invoke the `onclick` event handler defined in the submit element (this is a framework generated code, so I don't have control over it).

In JavaScript, you can call a function in multiple ways.

1. You can simple use the name of the function to call it: `doSomething()`.
2. In case of anonymous function, you can directly invoke it: `(function(){}());` This is known as [IIFE] (http://en.wikipedia.org/wiki/Immediately-invoked_function_expression "Immediately Invoked Function Expression").
3. You can either use `call` or `apply`. For example, `doSomething.apply(context, [])` / `doSomething.call(context, arg1, arg2)`.

So, I can use the third approach to invoke the `onclick` event handler here, as shown below.

```javascript
(function(){
  $('#radioBtnId').on('click', function(event){
    var submitBtn = document.getElementById('submitBtnId');
    submitBtn.onclick.apply(submitBtn);
  });
}());
```

That finally fixed it in IE8 and other browsers obliged too!
```


IE8 and Triggering event on hidden submit button


Day one of [JSFoo][1] is just got over. Went to the event with lot of expectations and came back with some new ideas/topics to explore. Here's a summary of what I learnt from today's sessions.

[1]: http://jsfoo.in

Except the keynote, rest of the sessions simultaneously happened in [two tracks][2]. So, I had to opt for one session while missing the other one. Anyway, the organizers seems to be recording the whole event. So, I hope I can catch up with the sessions I missed later in video format.

[2]: http://jsfoo.in/2012/#schedule

The first session I chose was '**Scaling node at Errorception**' by [Errorception][3] founder, [Rakesh Pai][4]. As I'm exploring node for my own web app, its very obvious for me to go for this. The speaker talked about how he's running Errorception on Node Mongodb stack. The highlights from his speech was:

[3]: http://errorception.com/ "Errorception"
[4]: http://blog.rakeshpai.me/ "Rakesh Pai"

1.  Don't write monolithic app. Instead break them into several micro apps (front end, queue processor, etc). This helps you to maintain it without much pain and deploy/take down the apps without affecting each other.
2.  Build a Queue layer for inter-app communication. That way, even if you take down a app, the messages won't be lost and they'll just be there in the queue until your app pick them up. He seems to be using **redis **for this purpose at Errorception.
3.  CPU bound app? Run away from node.

Then there was a 30 minutes of Q/A session about '**Web Storage**'. The presenter talked about different options for storing data locally at browser. It was new information to me that developers (ab)used the **window.name **property in order to persist data. This hack is totally an insecure way to preserve data and should never be considered for anything secure.

After a delicious lunch (I always complain about food in Bangalore, so when I say delicious, it is DELICIOUS!), I sit there in the '**Create JS**' session by [Harish Sivaramakrishnan][5].\*\* \*\*He totally inspired the audience by building a game from scratch in 45 minutes using [CreateJS][6] library. This library lets you to draw objects on Canvas instead of directly manipulating pixels by hand. A totally cool JS lib and if you are into game/visual programming using Canvas, you shouldn't miss this one.

[5]: http://hsivaram.com/
[6]: http://www.createjs.com/#!/CreateJS

The final sessions I attended were about using JQuery Deferred instead of inner-nesting callbacks and I18N Wikimedia libraries. Both provided some good information which I'll be using in my next projects.

Final session of the day was from Rakesh Pai who demoed his project of Controlling a toy car using Node server. He'd integrated the toy car with the Raspberry pi computer and ran the node server in it. A cool hardware hack, received great appreciation from the crowd.

With that the first day got over.


#js (2)