pdf thumbnails like in ibooks on the ipad or iphone

i need to create a pdf reader with an overview page showing thumbnails of the pdf. like with the pdfs in ibooks. what would be the best approach for that? i am thinking about using a uiscrollview and placing uiviews with tiledlayers for pdf rendering? 开发者_如何学Pythonhow can i best determine which view is visible and recycle them accordingly?

thanks

joerg

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Apple has sample code to get a PDF thumbnail on their developer site. I believe it is in the Quartz2d Programming Guide (unfortunately the site is down for me at the minute so I can't confirm).