Module development and code questions

Hello there!

I have a custom entity with a bunch of bundles. I am trying to build a custom views field that I can attach to a view that looks for a specific field on the entity, and displays it in the view. 

In a content type I have various fields and among these I have 2 select list fields (the first text list and the second entity reference).
When I make the choice in the first select I would like the second to be updated with only the nodes connected to the first
I have done various tests and read various articles (some have caused me confusion because they talk about writing all the code in form alter without using the callBack), but it is not clear to me how to do it
In the first select I inserted the callback and wrote this code

Hi,

I have a problem with div id="off-canvas".

This div contains:

<button class="mm-tabstart mm-sronly" aria-hidden="true" role="presentation"></button>

This code cause errors at wave accessibility tool.

Unfortunately, this tool is checking all the code even if there is the correct label aria-hidden="true" or/and role="presentation".

Currently I have 2 video in my FlexSlider but the problem that I'm facing now is when i press play button for my first video and when I press play button for the next video in the next slider,how to stop the video that been playing in the first slider.Does anyone have any solution for this?I've tried following this http://flexslider.woothemes.com/video.html but still can't get it right.Thanks in advance.

Hello I'm new in Drupal 7,

Currently I'm facing a few problem in my Drupal 7.In my Drupal 7 page, I would like to count how many people visited my page for today , monthly and the total people visited my site.Does anyone know the solution for it or any suitable modules that can be implement on it?Thanks in advance.

Ok so we have this module with a js-file that has this block of code in it:

Drupal.doSomeStuff = function (variable1, variable2) {
  // do stuff and return value
};

And in one js-file of our template I need to call this and make it run automatically when the page is loaded. If I do it like this: