Q:

Disable fade In effect on second click of the element

I have created a custom Jquery tab, It's working fine but there I need a small change that I don't need fadeIn effect on second click of the current tab item means there need $(".tab_container") show as normally. How can I achieve that? 
//custom tab

$(".tab_container").hide();
$('.tab_container:first').show();
$('.tab ul li a').click(function () {
    var tab = $(this).attr("href");
    $('.tab ul li a').removeClass('active');
    $(".tab_container").hide();
    $(this).addClass('active');
    $(tab).fadeIn();
    return false;
});

Fiddle : http://jsfiddle.net/nikhilvkd/h5maycuc/

A:

I've updated your code as shown below. I've added an extra variable called "currentTab" and that will hold the current tab name. The time when click on the tab,checking the selected tab with the variable "currentTab". If the condition is true, using the jquery show() method instead of the fadeIn() to show the tab. Else using the fadeIn() method and update the "currentTab" variable with the newly selected tab name. 
var currentTab=$('.tab ul li a:first').attr("href");

    $(".tab_container").hide();
    $('.tab_container:first').show();
    $('.tab ul li a').click(function () {
        var tab = $(this).attr("href");
        $('.tab ul li a').removeClass('active');
        $(".tab_container").hide();
        $(this).addClass('active');
        if(currentTab==$(this).attr("href"))
        {
            $(tab).show();
        }
        else
        {
             $(tab).fadeIn();
            currentTab=$(this).attr("href");
        }
        return false;
    });

