Vertical aligning an absolute positioned div inside a containing div

Question

I'm using the jQuery Cycle plugin to rotate images in a slideshow type fashion. That works fine. The problem I'm having is getting these images (of different sizes) to center in the containing div. The images are inside a slidshow div that has it's position set to absolute by the Cycle plugin.

I've tried setting line-height/vertical-align and whatnot but no dice. Here is the relevant HTML and CSS

HTML:

<div id="projects">
  <div class="gallery">
     <span class="span1">&#9668;</span><span class="span2">&#9658;</span>
        <div class="slideshow">
          <img src="images/img1.png"  />
          <img src="images/img1.png"  />
          <img src="images/img1.png"  />
        </div>
  </div>
</div>

CSS:

#main #home-column-2 #projects
{
  width: 330px;
  background: #fefff5;
  height: 405px;
  padding: 12px;
}

#main #home-column-2 #projects .gallery
{
  width: 328px;
  height: 363px;
  position: relative;
  background: url('images/bg-home-gallery.jpg');
}

#main #home-column-2 #projects .gallery img
{
  position: relative;
  z-index: 10;
}

And in case you want to see it, the jQuery:

$('#home-column-2 #projects .gallery .slideshow').cycle(
{
   fx: 'scrollHorz',
   timeout: 0,
   next: "#home-column-2 #projects .gallery span.span2",
   prev: "#home-column-2 #projects .gallery span.span1"
});

Any ideas on getting these images to center?

Answer 1

Try this:

http://www.brunildo.org/test/img_center.html

Vertical centering is a pain! Here's what the W3C page says about the vertical center:

CSS level 2 doesn't have a property for centering things vertically. There will probably be one in CSS level 3. But even in CSS2 you can center blocks vertically, by combining a few properties. The trick is to specify that the outer block is to be formatted as a table cell, because the contents of a table cell can be centered vertically.

Answer 2

This method involves a little jquery, but works fantastic in most situations... let me explain:

if all the images of the slideshow are contained within their own element div pos:absolute and those images are pos:relative, then on a $(window).load() you can run a .each() and find each img in the slideshow and adjust it's top positioning to be offset a certain number of pixels from the top..

jcycle automatically sets each parent div containing the image to pos:absolute on every onafter() so it's useless to apply this pos adjustment to them... instead target each img you have set to pos:relative...

Here is the example:

$(window).load(function() {

  // move all slides to the middle of the slideshow stage
  var slideshowHeight = 600; //this can dynamic or hard-coded

  $('.slideImg').each(function(index) {

    var thisHeight = $(this).innerHeight();
    var vertAdj = ((slideshowHeight - thisHeight) / 2);
    $(this).css('top', vertAdj);

  });

});

and this is the html it's working on...

<div class="slideshow" style="position: relative; ">

   <div style="position: absolute; top: 0px; left: 0px; display: none; width: 1000px; height: 600px; " id="img0">
       <img class="slideImg" src="/images/picture-1.jpg" style="top: 0px; "><!-- the style=top:0 is a result of the jquery -->
   </div>


   <div style="position: absolute; top: 0px; left: 0px; display: none; width: 1000px; height: 600px; " id="img1">
       <img class="slideImg" src="/images/picture-1.jpg" style="top: 89.5px; "><!-- the style=top:89.5px is a result of the jquery -->
   </div>


   <div style="position: absolute; top: 0px; left: 0px; display: none; width: 1000px; height: 600px; " id="img2">
       <img class="slideImg" src="/images/picture-1.jpg" style="top: 13px; "><!-- the style=top:13px is a result of the jquery -->
   </div>


</div>

just make sure

.slideImg {
    position:relative;
}

I think that's everything... I have an example, but it's on a dev site.. so this link might not last.. but you can take a look at it here: http://beta.gluemgmt.com/portfolio/rae-scarton-editorial.html