Jquery Firefox error in finding position() of a DIV

Question

Hello, I am facing a weird issue with firefox, I have a DIV tag with ID="popup_layer". I'm using Jquery to find this DIV which works fine :

var rightPosition=$j("#popup_layer")

But when I try to find the position of the DIV:

var rightPosition=$j("#popup_layer").position().left;

I get the following exception in Firebug:

[Exception... "Could not convert JavaScript argument arg 0 [nsIDOMViewCSS.getComputedStyle]" nsresult: "0x80570009 (NS_ERROR_XPC_BAD_CONVERT_JS)" location: "JS frame :: http://localhost:20094/Scripts/CombineJS.ashx?JSFiles=/Scripts/jquery-1.2.6.min.js;%20%20%20%20/Scripts/PDP/newModalBox.js;%20%20%20%20/Scripts/CookieHelpers.js;%20%20%20%20popupLayer.js;%20%20%20%20/BE/Scripts/scripts.js; :: anonymous :: line 23" data: no]

Answer 1

For some reason when i remove the style on my div it starts to work

<div id="popup_layer" style="display:none;">

To

<div id="popup_layer">

totally weird !

Answer 2

You cannot retrieve the dimensions or position of a DOM element with display:none. By definition, the element is not supposed to exist rendered on the page, hence it takes no space.

I suggest leaving your element visible initially, getting the dimensions you want, then applying "display:none" after you're done measuring it.

Alternatively you could use "visibility:hidden" instead.