jQuery how to make slideToggle applies one each item and hide others when one selected
<p>I have asked a question here: 
<a href="http://stackoverflow.com/questions/16532223/jquery-how-to-make-slidetoggle-applies-one-each-item/16532308#16532308"><strong>jQuery how to make slideToggle applies one each item</strong></a></p>

<p>and I have got the right answer here: <a href="http://jsfiddle.net/az8T7/3/" rel="nofollow"><strong>FIDDLE</strong></a></p>

<pre><code>&lt;div class="items"&gt;
    &lt;div class="warp"&gt;
        &lt;span class="change"&gt;Tester&lt;/span&gt;
         &lt;span class="click"&gt;expand&lt;/span&gt;
    &lt;/div&gt;
    &lt;div class="invisible"&gt;
        &lt;div class="red"&gt; red &lt;/div&gt;
        &lt;div class="black"&gt; black &lt;/div&gt;
    &lt;/div&gt;
&lt;/div&gt;

&lt;div class="items"&gt;
    &lt;div class="warp"&gt;
        &lt;span class="change"&gt;Tester&lt;/span&gt;
         &lt;span class="click"&gt;expand&lt;/span&gt;
    &lt;/div&gt;
    &lt;div class="invisible"&gt;
        &lt;div class="red"&gt; red &lt;/div&gt;
        &lt;div class="black"&gt; black &lt;/div&gt;
    &lt;/div&gt;
&lt;/div&gt;

&lt;div class="items"&gt;
    &lt;div class="warp"&gt;
        &lt;span class="change"&gt;Tester&lt;/span&gt;
         &lt;span class="click"&gt;expand&lt;/span&gt;
    &lt;/div&gt;
    &lt;div class="invisible"&gt;
        &lt;div class="red"&gt; red &lt;/div&gt;
        &lt;div class="black"&gt; black &lt;/div&gt;
    &lt;/div&gt;
&lt;/div&gt;
</code></pre>

<p>jQurey </p>

<pre><code>$(".warp").click(function () {
    var $warp = $(this);

    $warp.next(".invisible").slideToggle("slow", function () {
        if ($(this).is(':visible')) {
            $warp.removeClass('bg');
        }else{            
            $warp.find('span.click').css('visibility', 'visible');  
            $warp.addClass('bg');
        }
    });

    $warp.find('span.click').css('visibility', 'hidden');      
  });
</code></pre>

<p>My question is that, when one is selected how to slideToggle the other <code>invisible</code> divs
Thanks</p>
