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POHow to notify observer when an Object changes?
 

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  1. POHow to notify observer when an Object changes?
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    <p><strong>Short version: Is there a way to make sure an observer gets notified of a change, no matter what, even if Ember doesn't think a property has changed?</strong></p> <p>In general, the ember observer pattern works for me, but here I'm stuck. I'm not sure if this is a bug or whatnot, or feature, but something about this bothers me.</p> <p>I would be very happy with, in this occassion, some form of <code>myinstance.fireNotificationsNoMatterWhat("cache")</code>, but I can't find something like that in the code. Is there something I'm missing?</p> <p>Sample code below showing the problem.</p> <pre><code>&lt;!DOCTYPE html&gt; &lt;html&gt; &lt;head&gt; &lt;title&gt;emberjs notification test&lt;/title&gt; &lt;!-- using current (at the time) version 0.9.5, from emberjs.com starter kit. --&gt; &lt;script src="jquery-1.6.1.min.js"&gt;&lt;/script&gt; &lt;script src="ember-0.9.5.min.js"&gt;&lt;/script&gt; &lt;script&gt; Test = Ember.Application.create({}); // I don't want an arrayproxy this time, and would be happy to find // out if there is some form of ObjectProxy? Test.cacheObject = Ember.Object.create({ "cache": {}, "add": function(key, value) { // In other situations, I don't need // propertyWillChange/propertyDidChange, but here // I'm stuck, and I can't notify listeners when my // cache changes, so I figured I'd try out // these commands, which don't work, either. this.propertyWillChange("cache"); var cache = this.get("cache"); cache[key] = value; this.set("cache", cache); this.propertyDidChange("cache"); }, }); // Contrived watcher. Test.watcher = Ember.Object.create({ // One of the many ways I've tried to bind to the // the object to get the observer to fire. "cacheBinding": "Test.cacheObject.cache", "obs": function() { // Ideally, whenever I call Test.cacheObject.add in different call // stacks I should be notified. console.log("cache has changed:"); console.log(this.get("cache")); }.observes("cache"), }); setTimeout(function() { // I get notified on the first add... Test.cacheObject.add("hello", "world"); }, 500); setTimeout(function() { // ...but I will not get notified on the second, or any subsequent addition. Test.cacheObject.add("and", "universe"); }, 1000); &lt;/script&gt; &lt;/head&gt; &lt;body&gt; &lt;h1&gt;emberjs notification test&lt;/h1&gt; &lt;h2&gt;Please open your console to see the console.log output.&lt;/h2&gt; &lt;/body&gt; &lt;/html&gt; </code></pre> <p><strong>EDIT:</strong> It looks like there are short term fixes to this problem, however after trying out my own "fix", and trying out Roy's suggestion below, I think my core question will not be answerable until this <a href="https://github.com/emberjs/ember.js/issues/466" rel="nofollow">enhancement request</a> gets some love from the busy ember team. I can wait for that if it eventually gives me what the ArrayProxy gives me.</p>
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