Build Multiple Asset Picker
Learn how to request device photo library permissions from the user, then fetch the photo library's collections when authorized.
In this episode, learn how to display the various image collection titles in the asset picker's table view.
Set up the picker's table to navigate to the various photo collections, then set up the picker's collection view to load and display the collections' photos.
Persist photo selections between asset picker collections such that selection checkmarks display appropriately.
Use PHCachingImageManager to cache the images in and adjacent to the visible scrolling window, then load the collection view's images from that cache.
Manipulate Assets to Generate Collages
Create a photo album for the collages (i.e. "Stitches") or fetch the album if it already exists, then set up a collection view to display that album's images.
Create a new photo asset with a collage of the selected images, save it to the Stitches album, then load a high quality version of the image for display.
"Favorite," "unfavorite" and delete images; set the photo picker's selected image set to the assets referenced in the collage's adjustment data so the user can edit the selections to update the collage.
Implement observers to detect changes in the device's photo library, then update the app's photo preview, table view and collection view appropriately.
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算法技术手册
George T. Heineman、Gary Pollice、Stanley Selkow / 杨晨、李明 / 机械工业出版社 / 2010-3 / 55.00元
《算法技术手册》内容简介:开发健壮的软件需要高效的算法,然后程序员们往往直至问题发生之时,才会去求助于算法。《算法技术手册》讲解了许多现有的算法,可用于解决各种问题。通过阅读它,可以使您学会如何选择和实现正确的算法,来达成自己的目标。另外,书中的数学深浅适中,足够使您可以了解并分析算法的性能。 较之理论而言,《算法技术手册》更专注于应用。《算法技术手册》提供了高效的代码解决方案,使用多种语言......一起来看看 《算法技术手册》 这本书的介绍吧!