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POWhat's the fastest way in iOS to retrieve the number of songs for a specific artist?
 

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  1. POWhat's the fastest way in iOS to retrieve the number of songs for a specific artist?
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    <p>I am trying to retrieve all the artists on the local iOS device, and for each artist, the number of songs available for that artist.</p> <p>I currently am doing this in a straight-forward fashion, by querying for all artists, and for each artist, counting the number of items (songs) in its collection:</p> <pre><code>MPMediaQuery *query = [[MPMediaQuery alloc] init]; [query setGroupingType:MPMediaGroupingArtist]; NSArray *collections = [query collections]; for (MPMediaItemCollection *collection in collections) { MPMediaItem *representativeItem = [collection representativeItem]; int songs = [[collection items] count]; // do stuff here with the number of songs for this artist } </code></pre> <p>However, this doesn't seem very efficient, or at least, it's slower than I had anticipated.</p> <p>On a demo iPhone 4 device with several hundred artists, the above code took about 7 seconds to run. When I commented out the line that obtains the count of "collection items," the time is reduced to 1 second. </p> <p>So I am wondering if there is a faster way to retrieve the song counts for artists than what I am doing above?</p> <hr> <p><strong>Update 09/27/2011.</strong> I see that I can simplify the song count retrieval for an artist using this:</p> <pre><code>int songs = [collection count]; </code></pre> <p>Rather than what I was doing:</p> <pre><code>int songs = [[collection items] count]; </code></pre> <p>However, in reality this has had little effect on performance.</p> <p>I borrowed an iPhone 3G to try the performance of this issue on a slower device. </p> <p>My code takes 17.5 seconds to run on this 3G with only 637 songs spread across 308 artists.</p> <p>If I comment out the line that retrieves the number of songs, the same device finishes in only 0.7 seconds...</p> <p>There must be a faster way to retrieve number of songs per artist on an iOS device.</p>
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    1. USMason G. Zhwiti
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