iOS Programming: The Big Nerd Ranch Guide, Second Edition

Zooming

To add zooming, you need to give the scroll view a delegate. In HypnosisterAppDelegate.h, declare that HypnosisterAppDelegate conforms to the UIScrollViewDelegate protocol:

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 ​ ​ ​ ​<​U​I​A​p​p​l​i​c​a​t​i​o​n​D​e​l​e​g​a​t​e​,​ ​U​I​S​c​r​o​l​l​V​i​e​w​D​e​l​e​g​a​t​e​>​

Figure 6.5  HypnosisView in UIScrollView

Open HypnosisterAppDelegate.m. In application:​didFinishLaunchingWithOptions:, set the delegate and the limits of the zoom:

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