jQuery: Get height of hidden element in jQuery

I ran into the same problem with getting hidden element width, so I wrote this plugin call jQuery Actual to fix it. Instead of using

$('#some-element').height();

use

$('#some-element').actual('height');

will give you the right value for hidden element or element has a hidden parent.

Full documentation please see here. There is also a demo include in the page.

Hope this help :)

You are confuising two CSS styles, the display style and the visibility style.

If the element is hidden by setting the visibility css style, then you should be able to get the height regardless of whether or not the element is visible or not as the element still takes space on the page.

If the element is hidden by changing the display css style to "none", then the element doesn't take space on the page, and you will have to give it a display style which will cause the element to render in some space, at which point, you can get the height.

I've actually resorted to a bit of trickery to deal with this at times. I developed a jQuery scrollbar widget where I encountered the problem that I don't know ahead of time if the scrollable content is a part of a hidden piece of markup or not. Here's what I did:

// try to grab the height of the elem
if (this.element.height() > 0) {
    var scroller_height = this.element.height();
    var scroller_width = this.element.width();

// if height is zero, then we're dealing with a hidden element
} else {
    var copied_elem = this.element.clone()
                      .attr("id", false)
                      .css({visibility:"hidden", display:"block", 
                               position:"absolute"});
    $("body").append(copied_elem);
    var scroller_height = copied_elem.height();
    var scroller_width = copied_elem.width();
    copied_elem.remove();
}

This works for the most part, but there's an obvious problem that can potentially come up. If the content you are cloning is styled with CSS that includes references to parent markup in their rules, the cloned content will not contain the appropriate styling, and will likely have slightly different measurements. To get around this, you can make sure that the markup you are cloning has CSS rules applied to it that do not include references to parent markup.

Also, this didn't come up for me with my scroller widget, but to get the appropriate height of the cloned element, you'll need to set the width to the same width of the parent element. In my case, a CSS width was always applied to the actual element, so I didn't have to worry about this, however, if the element doesn't have a width applied to it, you may need to do some kind of recursive traversal of the element's DOM ancestry to find the appropriate parent element's width.

You could do something like this, a bit hacky though, forget position if it's already absolute:

var previousCss  = $("#myDiv").attr("style");

$("#myDiv").css({
    position:   'absolute', // Optional if #myDiv is already absolute
    visibility: 'hidden',
    display:    'block'
});

optionHeight = $("#myDiv").height();

$("#myDiv").attr("style", previousCss ? previousCss : "");