JQuery/JavaScript addClass doesn't work -

i have div contains elements. when click on 1 element action occur. during action time want make div colors change black & white , after action reset color.

so create simple css3 class :

gray {     background-color:red;     -moz-filter: grayscale(100%);     -webkit-filter: grayscale(100%);     filter: grayscale(100%); } 

and in script have 2 functions :

function enablewaitstate( ) {    $($("#chart")).addclass( "gray");  }  function disablewaitstate( ) {     $($("#chart")).removeclass( "gray"); } 

in javascript code write method called when clicking on button:

function back() {     enablewaitstate( );      // here doing javascript code     disablewaitstate(  ); } 

}

unfortunately doesn't work. if make ajax call between enablewaitstate() , disablewaitstate(), works!

any ideas?

you need remve additional $() selector.

function enablewaitstate( ) {    $("#chart").addclass( "gray");  }  function disablewaitstate( ) {     $("#chart").removeclass( "gray"); } 

also code work after chart element loaded in dom. can use console check that:

 console.log($("#chart").length)