As a courtesy, this is a full free rendering of my book, Programming iOS 6, by Matt Neuburg. Copyright 2013 Matt Neuburg. Please note that this edition is outdated; the current books are iOS 13 Programming Fundamentals with Swift and Programming iOS 13. If my work has been of help to you, please consider purchasing one or both of them, or you can reward me through PayPal at http://www.paypal.me/mattneub. Thank you!
This part of the book is about the things that appear in an app’s interface. All such things are, ultimately, views. A view is a unit of your app that knows how to draw itself. A view also knows how to sense that the user has touched it. Views are what your user sees on the screen, and what your user interacts with by touching the screen. Thus, views are the primary constituent of an app’s visible, touchable manifestation. They are your app’s interface. So it’s going to be crucial to know how views work.