mail_view | Visual email testing | Testing library

I have next problem, I probably need to change div's content by clicking on another div, now I will explain it more detailed:

I am using MVC to build simple application which is about retreiving and sending messages, and now I am working on Inbox view, In my view I'm having loaded list of messages (which are retreived from my controller) for logged user, and right part of view is reserved to view a content of clicked message (which is located and listed in left part on my view as on image below), and this is how it looks (ilustration not real image from my app, but same order of controls, content etc):

As you can see guys, my view is separated into left and right part, on the left is list of messages for logged user, and on the right content of clicked message should be shown, I guess this must be done using javascript/ajax, but I almost had not experience in it, I don't know how can I on message click take message id or whatever, and by that filter right div's content (I guess that is the point).

Here is my view code: