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    <p>The biggest thing you can watch out for is events, and how you assign them.</p> <p>For instance, take this scenario (since you haven't provided one):</p> <pre><code>&lt;div id="ajaxResponseTarget"&gt; ... &lt;/div&gt; &lt;script type="text/javascript"&gt; $(someButton).observe('click', function() { new Ajax.Updater($('ajaxResponseTarget'), someUrl, { onSuccess: function() { $$('#ajaxResponseTarget .someButtonClass').invoke('observe', 'click', function() { ... }); } }); }); &lt;/script&gt; </code></pre> <p>This will create a memory leak, because when <code>#ajaxResponseTarget</code> is updated (internally, Prototype will use <code>innerHTML</code>) elements with <code>click</code> events will be removed from the document without their events being removed. The second time you click <code>someButton</code>, you will then have twice as many event handlers, and garbage collection can't remove the first set.</p> <p>A way to avoid this is to use event delegation:</p> <pre><code>&lt;div id="ajaxResponseTarget"&gt; ... &lt;/div&gt; &lt;script type="text/javascript"&gt; $('ajaxResponseTarget').observe('click', function(e) { if(e.element().match('.someButtonClass')) { ... } }); $(someButton).observe('click', function() { new Ajax.Updater($('ajaxResponseTarget'), someUrl); }); &lt;/script&gt; </code></pre> <p>Because of the way DOM events work, the "click" on <code>.someButtonClass</code> will fire also on <code>#ajaxResponseTarget</code>, and Prototype makes it dead simple to determine what element was the target of the event. No events are assigned to elements <em>within</em> <code>#ajaxResponseTarget</code>, so there is no way for replacing its contents to orphan events from targets within.</p>
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    1. CO+1 Good info, although I'm never creating any new events after the initial page load. Still trying to figure out what I'm doing that would cause the issue.
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    2. COIf you're not creating any events... why did you accept this as your answer?
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Detail views are divided into sections. All the information in the data section comes from columns in the selected row. The other sections display data from other, related rows.

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