Merging content and layout to create the final presentation, Collection View Programming Guide for iOS
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The layout object provides layout metrics, Collection View Programming Guide for iOS
————————————————Messages sent during stack changes, View Controller Catalog for iOS
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Responder chains in an app, Using Responders and the Responder Chain to Handle Events
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View object, Cocoa Application Competencies for iOS
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Cocoa version of MVC as a compound design pattern, Concepts in Objective-C Programming
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