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copied!<p>Your code will work but it is not optimal.</p> <p>I forked your jsFiddle code and added logging to demonstrate it:</p> <ul> <li>Open <a href="http://jsfiddle.net/jvandemo/tDhgv/1/" rel="nofollow">http://jsfiddle.net/jvandemo/tDhgv/1/</a></li> <li>Open the console in your browser</li> <li>Type something in the input fields and you will notice that the <code>filterItems</code> runs 9 times every time the <code>$scope.query</code> changes</li> </ul> <p>So why is this?</p> <p>Well, there are 2 reasons:</p> <ol> <li>Your function call is inside an ng-repeat so it gets called multiple times (as expected, no surprises here)</li> <li><p>There is an issue with your <code>filterItems</code> method.</p> <p>You have assigned the <code>filterItems</code> method to the inner <code>ng-repeat</code>. Therefore Angular will automatically watch the result of the function for you and 'refresh' when it changes.</p> <p>However, inside your <code>filterItems</code> code you make an immediate change to the data Angular is watching for you by performing <code>g.filteredItemCount = ret.length</code> causing Angular to perform another 'refresh' since it detects a new change.</p> <p>If you were to comment out that single ine of code, you would immediately see a drop in number of times the method would run.</p></li> </ol> <p>So what's a better way?</p> <p>In your case I would:</p> <ul> <li>Define a watcher for <code>$scope.query</code></li> <li>Filter the data in your watcher and store it separately (to leave the original data untouched)</li> <li>Loop through the filtered data with the <code>ng-repeat</code> tags</li> </ul> <p>Your code will be cleaner, faster and more efficient which is important if your data set would be much bigger.</p> <p>I created a jsFiddle for your convenience: <a href="http://jsfiddle.net/jvandemo/VeLEJ/1/" rel="nofollow">http://jsfiddle.net/jvandemo/VeLEJ/1/</a> </p> <p>If you open the console, you will see that the code only runs once when <code>$scope.query</code> changes instead of 9 times before.</p> <p>Visually the result is the same, but behind the scenes there is quite a difference...</p> <p>Hope that helps!</p> <hr> <p>UPDATE: </p> <p>An approach for better performance is to restructure the data (once after loading the data).</p> <p>I have created a jsFiddle with sample code to demonstrate it: <a href="http://jsfiddle.net/jvandemo/fTE5R/1/" rel="nofollow">http://jsfiddle.net/jvandemo/fTE5R/1/</a></p> <p>The data is restructured to avoid <code>forEach</code> cycles and to avoid as many loops as possible and to allow the <code>query</code> object to be applied directly to the items in the directive.</p> <p>This looks a lot like the original code but without the need for calling filtering functions inside the <code>scope</code>.</p> <p>If your application can deliver the data in the format of <code>$scope.items</code> the whole process would even be faster and the optimization step could be skipped.</p> <p>Hope that helps!</p>

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