1. iOS Training
(Intermediate)
Gurpreet Singh
Sriram Viswanathan
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2. Topics
 Protocols and Delegates
 Categories and Selectors
 Views and View Controllers
 Introduction to View Controllers
 Types of View Controllers
 Hands on example for
 Creating a View Controller
 Manipulating Views
 Adding Content to Application
 Working with Images
 Adding Simple Animation
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3. Protocols and Delegates
Protocol
 Protocols declare methods that others are expected to implement
 Similar to interfaces in other languages
 Protocol does not require .m file.
 Protocol can have @optional methods
Delegate
 It allows one object to delegate part of its behavior to be handled by
another object.
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4. Topics
 Protocols and Delegates
 Categories and Selectors
 Views and View Controllers
 Introduction to View Controllers
 Types of View Controllers
 Hands on example for
 Creating a View Controller
 Manipulating Views
 Adding Content to Application
 Working with Images
 Adding Simple Animation
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5. Categories and Selectors
Categories:
 Lets you add methods to class without having access original code
 Access instance variable but can't add new ones
@implementation NSString (NumericComparison)
- (NSComparisonResult) compareNumerically:(NSString *) compareWithString {
// ADD NUMERIC SORTING LOGIC HERE
}
@end
Selectors:
 Selector is a way of specifying a method to call
@selector(methodName)
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6. Topics
 Protocols and Delegates
 Categories and Selectors
 Views and View Controllers
 Introduction to View Controllers
 Types of View Controllers
 Hands on example for
 Creating a View Controller
 Manipulating Views
 Adding Content to Application
 Working with Images
 Adding Simple Animation
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7. Introduction to View Controllers
 Link between application’s data and user interface
 View controllers are traditional controller objects in the MVC design
pattern
 Responsible for fetching/initializing models
 Every view controller that Apple provides extends from the
UIViewController class
 You Manage Your Content Using Content View Controllers
 A content view controller presents content on the screen using a view or a
group of views organized into a view hierarchy.
 Container View Controllers Manage Other View Controllers
 A container view controller contains content owned by other view controllers.
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8. Introduction to View Controllers
 Every view is controlled by only one view controller.
 Each view controller interacts with a subset of your app’s data.
 For example, the Photo controller needs to know only the photo to be displayed.
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9. Topics
 Protocols and Delegates
 Categories and Selectors
 Views and View Controllers
 Introduction to View Controllers
 Types of View Controllers
 Hands on example for
 Creating a View Controller
 Manipulating Views
 Adding Content to Application
 Working with Images
 Adding Simple Animation
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10. Types of View Controllers
Most commonly used UI View Controllers
UINavigationController
 Navigation Controllers Manage Stacks of Other View Controllers
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11. Types of View Controllers
UITableViewController
Interesting features:
•
•
Lazy loading
Grouping
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12. Types of View Controllers
UITabBarController
 Tab Bar Controllers Manage Independent Sets of View Controllers
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13. Types of View Controllers
UIPageViewController
 Page View Controllers Manage Paged Display of View Controllers
 Apps can use a page view controller to present a paged view of content
 The page view controller itself manages the display of one or more
content view controllers, each of which provides a single page of content.
UISplitViewController
 Split View Controllers Manage Two Panes of Information
 Apps can use a split view controller to manage two panes of
information, where both portions of the interface are themselves managed
by view controllers.
 This is interface is similar to a navigation controller, but it takes advantage
of the larger screen size of iPad to present more content at a time.
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14. Types of View Controllers
View Controllers at a glance
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15. Topics
 Protocols and Delegates
 Categories and Selectors
 Views and View Controllers
 Introduction to View Controllers
 Types of View Controllers
 Hands on example for
 Creating a View Controller
 Manipulating Views
 Adding Content to Application
 Working with Images
 Adding Simple Animation
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