Animate/Ease an element to position when other elements disappear

Question

Please take a look at this fiddle: http://jsfiddle.net/dhcyA/

Try clicking on a block. What I want is that when the other elements disapear, the selected block will animate/ease to his giving position instead of just jumping like it does now. Then the same animation repeats itself when clicking again on the box, but then back to place.

Maybe to keep in mind:
I'm using a reponsive design, which means those blocks can be vertical and horizontal after scaling the window.

Any redevisions on the fiddle or suggustions would be great!

Answer 1

Here is my solution.

On your existing markup, I added a wrapper division to calculate the position of boxes inside the wrapper. Like this

<div id="wrapper">
    <div class="block">
        <h2>I'm block 1</h2>
    </div>
    ....
</div>

To maintain the fluidness of the block, I created a function to position the block on the wrapper. Here is the function for position of the blocks:

var reposition = function() {
    wrapper = $("#wrapper");
    console.log(wrapper.innerWidth());
    pLeft = 0;
    pTop = 0;
    maxRowHeight = 0;
    $(".block").each(function(){
        if($(this).data('active')) {
            $(this).data('top', pTop);
            $(this).data('left', pLeft);
        } else {
            $(this).stop(0,0).animate({
              'top' : pTop + 'px',
              'left' : pLeft + 'px'
            });
        }
            pLeft += $(this).outerWidth() + parseInt($(this).css('marginLeft'));
            if($(this).height() > maxRowHeight) maxRowHeight = $(this).outerHeight() + parseInt($(this).css('marginTop')); //Find out the longest block on the row

            if(pLeft + $(this).next().outerWidth() + parseInt($(this).next().css('marginLeft')) >= wrapper.innerWidth()) {
               pLeft = 0;
               pTop += maxRowHeight;
               maxRowHeight = 0;
            }

    });    
};

Finally, the script to toggle the block

$(".block").click(function() {

    $(this).siblings().slideToggle('slow'); //Toggle other blocks

    if(!$(this).data('active')){ //if the block is not active
        $(this).data('left', $(this).position().left); //sets its left
        $(this).data('top', $(this).position().top);   // and top position
        $(this).animate({ //animate at the top and bottom
            top:0,
            left:0
        },'slow');

        $(this).data('active',true);

    }else{

        $(this).animate({ //animate to its last known position
            top:$(this).data('top'),
            left:$(this).data('left')
        },'slow');

        $(this).data('active',false);
    }
});

Demos

• Demo[Full] (Resize this to see the fluidness maintained)
• Demo[Full] (version showing variable heights)

Here is what this solutions gives:

• Remembers the last position and gradually animate to/from this position
• Block positions are calculated and animated on load and every resize
• Repositioning happens on $(window).resize() thus maintaining the fluid nature of the block, despite the use of position absolute
• Support variable heights
• Minor change on existing markup & CSS

Also fixed two issues extended by Gaby

• Accounts for each block margin independently
• Recalculates the position of the element after resize

Answer 2

Final Update

Here is a full working solution (pretty straight forward in my opinion) with JS to set the positioning (a simple calculation) and CSS transitions for the rest..

Demo at http://jsfiddle.net/gaby/pYdKB/3/

It maintains the fluidity of float:left and works with any number of elements, and you can keep the :nth-child for the styling, and it will also work if you want to leave more than one element visible..

javascript

var wrapper = $('.wrapper'),
    boxes = wrapper.children(),
    boxWidth = boxes.first().outerWidth(true),
    boxHeight = boxes.first().outerHeight(true); 

function rePosition(){
    var w = wrapper.width(),
        breakat = Math.floor( w / boxWidth ); // calculate fluid layout, just like float:left

    boxes
        .filter(':not(.go)')
        .each(function(i){
            var matrixX = ((i)%breakat)+1,
                matrixY = Math.ceil((i+1)/breakat);

            $(this).css({
                left:(matrixX-1) * boxWidth ,
                top: (matrixY-1) * boxHeight
            });
        });
}

$('.box').click(function(){
    $(this)
        .siblings()
        .toggleClass('go');// just add the go class, and let CSS handle the rest

    rePosition(); // recalculate final positions and let CSS animate the boxes
});

$(window).resize(rePosition);
$(window).trigger('resize');

CSS

.wrapper{
    position:relative;
}

.box{
    width:200px;
    height:100px;
    position:absolute;
    margin:5px;
    cursor:pointer;
    overflow:hidden;
    text-align: center;
    line-height: 100px;

        -moz-transition-property: top,left,width,height;
     -webkit-transition-property: top,left,width,height;
         -ms-transition-property: top,left,width,height;
          -o-transition-property: top,left,width,height;
             transition-property: top,left,width,height;

        -moz-transition-duration: 1s;
     -webkit-transition-duration: 1s;
         -ms-transition-duration: 1s;
          -o-transition-duration: 1s;
             transition-duration: 1s;
}

.go{
    height:0;
    width:0;
}

note: As @Athari correctly mentioned in the comments, you should include all browser prefixes for the widest support. (my initial answer only included moz / webkit and the standard)

---

Original Answer

You can not do it directly with your current HTML structure. The floated concept does not support it.

But if you can afford an extra wrapper, then it is no problem..

Just slide the contents of your extra wrapper element..

Put the float code on the wrapper element and use

$(document).ready(function() {

    $(".block-wrapper").click(function() {
        $(this).siblings().find('.block').slideToggle("slow");
    });

});

Demo at http://jsfiddle.net/gaby/t8GNP/

---

Update #1

If you need to move the clicked element to the top left and back, then you cannot really do it with CSS.

You will need to manually position them (through JS), set CSS transitions (or jquery), and apply the new positions once you click.

Later on you might want more than one to remain visible and reposition as well..

So you might want to take a look at the great Isotope plugin which can handle this and a multitude of more situations/layouts