How to make scrolling through images as fast as Apple's Photos app

Posted by clozach on Stack Overflow See other posts from Stack Overflow or by clozach
Published on 2010-05-21T22:57:18Z Indexed on 2010/05/21 23:00 UTC
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Filed under:

iphone

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uiscrollview

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slow

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image-loading

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three20

The Goal — On an iPhone, to browse through several hundred locally-stored jpgs using a UIScrollView.

The Problem — Like many others before me, I've tried implementing a scroll view based on Apple's Page Control sample code and found it lacking. The biggest issue I'm currently up against is that the sample code's architecture doesn't seem to scale. With just a few images loaded from disk, everything's fine. Once the number of images gets into the dozens, though, scrolling suffers terribly: the scrollview stutters mid-scroll with each new swipe.

The only code I've toyed with that comes even close to being reasonably responsive is Three20, but even there the performance doesn't hold a candle to Photos.

For now, I'm just using Three20, but a faster, custom solution would definitely be preferable.

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