Question

addClass doesn’t seem to work under certain circumstances for me. Have a look at the following code:

$("#my-div-container .my-sub-div li a").live('mouseover', function(e){
    e.preventDefault();

    var li_parent_elem = $(this).parent();
    li_parent_elem.siblings().removeClass();

    switch(true)
    {
        case (li_parent_elem.is("#my-div-container .my-sub-div li:first-child") == true):
            //alert("First");
            li_parent_elem.addClass("first");
        break;

        case (li_parent_elem.is("#my-div-container .my-sub-div li:last-child") == true):
            //alert("Last");
            li_parent_elem.addClass("last");
        break;

        default:
            //alert("Mid");                     
            li_parent_elem.addClass("mid");
    }
});

addClass doesn’t work for the first two case statements, only the default. However, when I uncomment the alert directives, I get the correct alert so I know the conditional statement is working.

I’m not sure what is wrong here, and I’d appreciate some assistance.

Answer 1

After a bit of fiddling I seem to have found a solution to this, even though I don’t really like it because I don’t understand why it works and the earlier code doesn’t.

Here’s the modified code:

$("#my-div-container .my-sub-div li a").live('mouseover', function(e){
e.preventDefault();

var li_parent_elem = $(this).parent();
li_parent_elem.siblings().removeClass();

switch(true)
{
    case (li_parent_elem.is("#my-div-container .my-sub-div li:first-child") == true):
        //alert("First");
        li_parent_elem.removeAttr("class").addClass("first");
    break;

    case (li_parent_elem.is("#my-div-container .my-sub-div li:last-child") == true):
        //alert("Last");
        li_parent_elem.removeAttr("class").addClass("last");
    break;

    default:
        //alert("Mid");                     
        li_parent_elem.addClass("mid");
}
});

I’m still at a loss why even when I removed the switch statement and used if-else with my earlier code, it didn’t work, but this does.

Maybe it’s a bug or something.