WordPress plugin development jquery conflict

Solution:

Before using $j you should declare it using .noConflict().

You can also use it for your plugin, WordPress require it most of the time because it use different libraries.

So at the to of your plugin write:

var $j = jQuery.noConflict(); //$j could be also j, or $r, everything you want, is a variable.

Then replace all your $ with your new variable used in the no conflict.

Hope it help.