make custom hoverCallback about laravel-morris-php HOT 1 CLOSED

<?php

echo Morris::area( 'morris-area' )
           ->xkey( [ 'y' ] )
           ->ykeys( [ 'a', 'b' ] )
           ->labels( [ 'Series A', 'Series B' ] )
           ->hoverCallback( 'function(index, options, content){var row = options.data[index];return "sin(" + row.x + ") = " + row.y;}' )
           ->data( [
                     [ "y" => '2006', "a" => 100, "b" => 90 ],
                     [ "y" => '2007', "a" => 75, "b" => 65 ],
                     [ "y" => '2008', "a" => 50, "b" => 40 ],
                     [ "y" => '2009', "a" => 75, "b" => 65 ],
                     [ "y" => '2010', "a" => 50, "b" => 40 ],
                     [ "y" => '2011', "a" => 75, "b" => 65 ],
                     [ "y" => '2012', "a" => 100, "b" => 90 ]
                   ] );