MVC + BDSM = MVVM?

Overview of architecture principles applied to Apple MVC. Common pitfalls and our vision of iOS Architecture evolution

1. MVC + BDSM = MVVM? July 2015
2. Alexey Demedeckiy iOS Developer Mentor
3. Agenda Architecture definition Process of development MVC approach Model layer BDSM practices MVVM
4. Architecture
5. Code is a set of entities that can store and transform data. Code is a set of entities that can store and transform data.
6. Design is a set of relationships between entities. Design is a set of relationships between entities.
7. Architecture is a set of rules which defines design. Architecture is a set of rules which defines design.
8. Architecture is meta design.
9. Architecture Quality checklist Simple Constant Predictable
10. Big architecture Relationships between classes Roles and contracts Files layout
11. Small architecture Code layout Code style
12. Process
13. Knowledge sharing
14. Iterations
15. KISS
17. Code should not predict changes
18. Architecture - should
19. Extreme architecture
20. Bad architecture
21. Bad Sprint 1 Sprint 2 Sprint 3 Design 1 Design 2 Design 3 + + Code = Design =
22. Extreme Sprint 1 Sprint 2 Sprint 3 Design 1 Design 2 Design 3 Code = Design =
23. MVC
24. Model View Controller View Controller Model update state actions updates commands
25. Massive ViewController Controller Network Database Business rules
26. Many ViewControllers Controller Network Database Business rules Controller Controller
27. Change cost Time cost Number of relationships
28. Do not change root. Change leafs.
29. Many ViewControllers Controller Network Database Business rules Controller Controller
30. Model Layer
31. Model of something is description of important parts.
32. Model can: hide process details abstract actions hide unneeded data
33. Many ViewControllers Controller Network Database Business rules Controller Controller
34. Many Models Model Network Database Business rules Model Model
35. Changes Soft changes Hard changes
36. Model is soft change buffer
37. Model View Controller View Controller Model update state actions updates change
38. MVC - FIXED!
39. BDSM Practices that helps
40. Bindings
41. Controller binds view to model data. Controller call model actions. Model change it’s data. View hook up changes.
42. Data-driven model
43. All model actions is -(void) Model data is always valid Model data is formatted for view
44. Stateless Controller
45. Model data is enough to fill UI Model store intermediate state View can animate from state to state
46. Mandatory
47. Code review B, D and S Architecture has priority over feature Task can`t be closed without code review.
48. BDSM Use bindings for model observations Delegate all process handling to Model Delegate all state handling to Model Keep all code in project consistent.
49. MVVM
50. Multiple Models Model Network Database Business rules Model Model
51. Single model Application Model Network Database Business rules
52. Application model has wide interface
53. Controllers problem
54. Application Model Controller Controller Controller
55. Each Controller can do anything
56. View Model to the rescue!
57. Application Model View Model View Model View Model
58. View model has thin interface
59. View model is Application model adapter for specific controller
60. View Controller View Model update state actions updates change
61. AM-VM-V-C ?
62. VC is a View from Application model perspective
63. MVVM = MVC
64. Summary
65. Abstraction level Ownership chain UIKIT Controller View Model Application Model Service Framework Service Interface
66. Questions and propositions skype: nobidon e-mail: dalog@me.com