As an app developer there is always pressure to understand and be able to address both major platforms. At first blush, coding for iOS seems quite different than for Android, perhaps due to the language differences between Objective-C and Java, and of course there is a different IDE and framework. With the introduction of Swift, this chasm seems much smaller. This talk will map Android and Java functionality to similar concepts in iOS using Swift. We’ll see the similarities and differences, focusing on framework concepts, and migrate a simple Android app to iOS.

1. iOS for Android
Developers
with Swift
David Truxall, Ph.D.
http://bit.ly/androidToIos

2. About Me
@davetrux
blog.davidtruxall.com

3. You
● Know Java
● Know Android
● Don’t know Swift
● Don’t know iOS
● Need a Mac

4. Goal
Learn basic iOS concepts for someone
familiar with Android
(using Swift)

5. Why?
● Do I hate Android now?
● Neither platform is “the winner”
● Clients want both platforms
● You can make more money
● Swift is the new hotness in mobile
● Objective-C

6. Agenda
1. Brief language intro
2. Project/Tool Structure
3. App Architecture
4. Coding Demo

7. Swift
● Object-oriented AND Functional
● C family
● Cleaner, simpler, safer than Objective-C
● Modern features

8. Compare
- (NSString*) concatenateString:(NSString*)stringA withString:(NSString*)stringB
{
NSString *finalString = [NSString stringWithFormat:@"%@%@", stringA, stringB];
return finalString;
}
func concatenateString(stringA: String, stringB: String) ->String {
let result = stringA + stringB
return result
}

9. Swift Features
● Closures
● Tuples and multiple return values
● Generics
● Structs that support methods
● Functional programming patterns

10. Java/Android Swift/iOS
import com.package.name; import frameworkname
int counter; var counter :Int
static final int LEVELS = 8; let levels = 8
private private
public public
- internal (*)
protected -
Language

11. Java/Android Swift/iOS
class Foo extends Bar {} class Foo : Bar
interface Baz{} protocol Baz
class Foo implements Baz{} class Bar : Baz {}
Foo(); init()
void doWork(String arg){} func doWork(arg: String) -> Void
Foo item = new Foo(); var item : Foo = Foo()
item.doWork(arg); item.doWork(arg)
Objects

12. Optionals
? - Has a value or no value at all (nil)
! - Implicitly Unwrapped Optional

13. Swift OO
class VideoMode {
var resolution : Resolution = Resolution()
var interlaced = false
let frameRate = 60.0
var name: String?
func setUpMode(modeName: String) -> Void {<do stuff>}
}

14. Swift Functional
func addTwoInts(a: Int, b: Int) -> Int {
return a + b
}
var addFunction: (Int, Int) -> Int = addTwoInts
func printMath(mathFunction: (Int, Int) -> Int, a: Int,
b: Int) {
println("Result: (mathFunction(a, b))")
}
printMath(addTwoInts, 3, 5)

15. Xcode
● Free
● It’s an IDE
● Click not double-click
● Virtual file organization

16. Demo

17. Application Architecture
Model - View - Controller
UI Organization and Plumbing

18. Model - View -Controller
Controller
ModelView
Update
User Action
Update
Notify

19. Android != Model-View-Controller
Activity
Provider
Layout
Update
Notify

20. iOS Model - View -Controller
ViewController
Custom ClassesUIView
Update via IBOutlet
Respond to IBAction
Update
Notify

21. UI Organization
Android iOS
Layout XML XIB (NIB)
- Storyboard
- IBOutlet
- IBAction
Intent ~ Segue

22. Lifecycle Events
Android iOS
onCreate (onCreateView) viewDidLoad
onStart viewWillAppear
onResume viewDidAppear
onPause viewWillDisappear
onStop viewDidDisappear

23. UI Elements
Android iOS
TextView UILabel
EditText (single line) UITextField
EditText (multi-line) UITextView
Button UIButton
RadioGroup SegmentedControl
CheckBox, ToggleButton UISwitch

24. Delegation
● Class has a property that is a protocol
● Second class implements the protocol
● Second class assigned to the variable in
the first class

25. Converting an App

26. Yet Another Shameless Plug
@davetrux
blog.davidtruxall.com
http://bit.ly/androidToIos

27. Resources
Apple's Swift iBook
Swift Developer Center
Migrating to Swift from Android Book
Empty Application template
http://bit.ly/androidToIos