Coordinate your app

Introduction to Coordinator's approach for resolving navigation in iOS applications.
Presented on internal tech talks at Freeletics.

Transcript

1. Coordinate your app Aydar Mukhametzyanov
2. • Intro to iOS navigation • Problems • Classic solution • Solution with Coordinators • Demo Agenda
3. • Intro to iOS navigation • Problems • Classic solution • Solution with Coordinators • Demo
4. Intro to iOS navigation UIViewController UINavigationController UIViewController UIViewController UIViewController UIViewController Navigation stack
5. UINavigationController Intro to iOS navigation UIViewController UIViewController Push - Pop
6. UINavigationController Intro to iOS navigation UIViewController Present - Dismiss UINavigationController UIViewController
7. • Intro to iOS navigation • Problems • Classic solution • Solution with Coordinators • Demo
8. Problems 1. Push next 2. Go back
9. E new D E new new D C Problems A B C visible Push next A B visible +1 +n
10. D E C E D Problems A B C visible Go back A B visible -1 -n
11. Problems 1. Push next 2. Go back +1 +n -1 -n
12. • Intro to iOS navigation • Problems • Classic solution • Solution with Coordinators • Demo
13. Classic solution Chained navigation
14. Classic solution Chained navigation E D A B C let vc = E() push(vc) +1
15. Classic solution Chained navigation E A B C D
16. Classic solution Chained navigation E A B C D P M N O D
17. D Classic solution ... func showNext() { let vc: UIViewController if isOneFlow { vc = E() } else { vc = P() } push(vc) } ... Chained navigation
18. Classic solution Chained navigation D E P … + Conditions
19. Classic solution Chained navigation E D A B C pop() -1
20. Classic solution Chained navigation E D A B C pop(to: c) -n
21. Classic solution Chained navigation E C … + How it was presented
22. Classic solution Chained navigation Screen object knows and does too much
23. • Intro to iOS navigation • Problems • Classic solution • Solution with Coordinators • Demo
24. Solution with Coordinators E D A B C
25. Solution with Coordinators E D A B C
26. Solution with Coordinators E D A B C Coordinator 1. done 2. init push 3. done 4. init push
27. Solution with Coordinators E D A B C Coordinator 1. done 2. init push 3. done 4. init push
28. Solution with Coordinators B Coordinator private let onDone: () -> () ... func donePressed() { onDone() } ... private func configuredA() -> A { let a = A(onDone: { self.navigationController? .push(configuredB()) }) return a } private func configuredB() -> B { let b = B(onDone: { self.navigationController? .push(configuredC()) }) return b } …
29. Solution with Coordinators E D A B C Coordinator
30. Solution with Coordinators E D A B C Coordinator I F G H
31. Solution with Coordinators E D A B C Coordinator I F G H Coordinator 2
32. Solution with Coordinators Coordinator Child coordinator private func startChildCoordinator() { let coord = ChildCoordinator(onFinish: { self.navigationController?.dismiss() }) navigationController?.present(coord.start()) } init(onFinish: @escaping () -> ()) { self.onFinish = onFinish } ... private func configuredI() -> I { let i = I(onDone: { self.onFinish() }) return i }
33. Solution with Coordinators E D A B C Coordinator Coordinator 2
34. Solution with Coordinators A B Coordinator Coordinator 2 Coordinator 3
35. Solution with Coordinators 1. Push next 2. Go back +1 +n -1 -n
36. Solution with Coordinators +1 +n E D A B C Coord A onDone() push(e) visible -1
37. Solution with Coordinators E D A B C Coord A +1 +n -1
38. Solution with Coordinators E D A B C Coord A P M N O D Coord B +1 +n -1
39. Solution with Coordinators 1. Push next 2. Go back +1 +n -1 -n
40. Solution with Coordinators A Coordinator E B C D visible -n
41. Solution with Coordinators D E Coordinator 2 A Coordinator B C -n visible onDone()
42. Solution with Coordinators Coordinator private func startChildCoordinator() { let topVC = navigationController!.topViewController let coord = ChildCoordinator(onFinish: { self.navigationController?.pop(to: topVC) }) navigationController?.push(coord.start()) } -n
43. Solution with Coordinators 1. Push next 2. Go back +1 +n -1 -n
44. Solution with Coordinators +1 +n -1 -n Chained navigation Coordinators OK, but dependencies OK, but dependencies OK NOT OK OK OK OK OK
45. • Intro to iOS navigation • Problems • Classic solution • Solution with Coordinators • Demo
46. Demo https://github.com/aydarin/mvvm-demo
47. Thank you! Questions