Good Intentions II: Enemy of the State

Originally presented at 360iDev in Denver, CO on August 19, 2015

In a world where ViewControllers shoulder the burden of managing ever-changing vagarities of application state logic and complex navigation stacks, one design pattern emerges from the past to lead us toward a better, brighter, and lighter future of app development.

In this sequel to last year’s blockbuster presentation, “Good Intentions: Building Better ViewControllers”, we will revive a venerable programming technique for explicitly defining application behaviors and thereby reducing the responsibilities of our much maligned ViewControllers.

Transcript

1. Good Intensions 2 Enemy of the State Jay Thrash @jaythrash 360iDev, Denver August 2015 Intentions
2. You Survived! 2015
3. You made it! or did you?
4. Good Intentions 2 Enemy of the State Jay Thrash @jaythrash 360iDev, Denver August 2015 “relax”
5. Intention
6. Intention “you keep using that word…”
7. Intention inˈten(t)SH(ə)n/ 1. a thing intended; an aim or plan.
8. Ambiguity Intention
9. BE OBVIOUS Intention
10. Previously, at
11. Jay Thrash @jaythrash 360iDev, Denver August 2014 A Path to Building Better ViewControllers Good Intentions
12. Jay Thrash @jaythrash 360iDev, Denver August 2014 A Path to Building Better ViewControllers Good Intentions Stores Techniques 3 Delegate(v) the DataSources Intentions
13. State
14. State Managing with intent
15. BOOL ENUM & State Managing
16. BOOL ENUM & Managing state
17. BOOL ENUM & Managing state ✓Easy to start ‣Minimal states ‣Quick to Conflict
18. BOOL ENUM & Managing state ✓Easy to start ‣Minimal states ‣Quick to Conflict ✓No Conflicts ‣From Any, to Any ‣No Rules
19. Managing state BOOL ENUM & ✓Easy to start ‣Minimal states ‣Quick to Conflict ✓No Conflicts ‣From Any, to Any ‣No Rules TOO AMBIGUOUS
20. State Machines
21. State Machines ancient art
22. State Machines ancient art
23. State Machines ancient art
24. “A mathematical model of logic. A state machine can be in one of a finite number of states. The machine is in only one state at a time; the state it is in at any given time is called the current state.” State Machines abstract
25. State Machines abstract
26. States State Machines abstract
27. State Machines abstract
28. Current State State Machines abstract
29. Transitions State Machines abstract
30. State Machines practical
31. State Machines  WWDC 2014 Advanced User Interfaces with Collection Views Session 232 practical
32. State Machines AAPLStateMachine practical
33. State Machines ✓ Simple Configuration ✓ Transition Logic “DSL” ✓ Conforms to SRP ✓ Facilitates Automated Testing practical
34. State Machines NSString * const AAPLLoadStateInitial = @"Initial"; NSString * const AAPLLoadStateLoadingContent = @"LoadingState"; NSString * const AAPLLoadStateRefreshingContent = @"RefreshingState"; NSString * const AAPLLoadStateContentLoaded = @"LoadedState"; NSString * const AAPLLoadStateNoContent = @"NoContentState"; NSString * const AAPLLoadStateError = @"ErrorState"; ✓Simple Configuration practical States
35. State Machines self.validTransitions = @{ AAPLLoadStateInitial : @[AAPLLoadStateLoadingContent], AAPLLoadStateLoadingContent : @[AAPLLoadStateContentLoaded, AAPLLoadStateNoContent, AAPLLoadStateError], AAPLLoadStateRefreshingContent : @[AAPLLoadStateContentLoaded, AAPLLoadStateNoContent, AAPLLoadStateError], AAPLLoadStateContentLoaded : @[AAPLLoadStateRefreshingContent, AAPLLoadStateNoContent, AAPLLoadStateError], AAPLLoadStateNoContent : @[AAPLLoadStateRefreshingContent, AAPLLoadStateContentLoaded, AAPLLoadStateError], AAPLLoadStateError : @[AAPLLoadStateLoadingContent, AAPLLoadStateRefreshingContent, AAPLLoadStateNoContent, AAPLLoadStateContentLoaded] }; ✓ Simple Configuration practical Transitions
36. State Machines ✓ Transition Logic “DSL” practical // NSString * const AAPLLoadStateLoadingContent=@“LoadingState”; I (void)somethingHappened { self.stateMachine.currentState = AAPLLoadStateLoadingContent; }
37. State Machines ✓ Transition Logic “DSL” practical // NSString * const AAPLLoadStateLoadingContent = @“LoadingState”; I (void)didEnterLoadingState { [self updatePlaceholder:self.placeholderView]; } I (void)didExitLoadingState { [self thatActionOnLeavingLoadingState]; }
38. State Machines practical AAPLStateMachine AAPLStateMachine Delegate MyClass AAPLStateMachine Delegate •Configure & Conform •Request & React •Validate •Initiate
39. State Machines ✓ Conforms to SRP practical AAPLStateMachine AAPLStateMachine Delegate MyClass AAPLStateMachine Delegate •Configure & Conform •Request & React •Validate •Initiate
40. BE OBVIOUS
41. State Machines Applied
42. State Machines Applied •async Data Sources •branching navigation •session management
43. State Machines Applied: Async Data Source
44. State Machines Applied: Async Data Source
45. State Machines Applied: Async Data Source
46. State Machines Applied: Async Data Source
47. State Machines Applied: Async Data Source
48. State Machines Initial Loading Content Content Loaded Refresh Content Error No Content Applied: Async Data Source
49. State Machines Initial Loading Content Content Loaded Refresh Content Error No Content Applied: Async Data Source
50. State Machines Initial Loading Content Content Loaded Refresh Content Error No Content Applied: Async Data Source
51. State Machines Initial Loading Content Content Loaded Refresh Content Error No Content Applied: Async Data Source
52. State Machines Initial Loading Content Content Loaded Refresh Content Error No Content Applied: Async Data Source
53. State Machines Initial Loading Content Content Loaded Refresh Content Error No Content Applied: Async Data Source
54. State Machines Initial Loading Content Content Loaded Refresh Content Error No Content Applied: Async Data Source
55. State Machines Applied: branching navigation
56. State Machines Applied: branching navigation
57. State Machines Applied: branching navigation
58. State Machines Applied: branching navigation Direct
59. State Machines Applied: branching navigation Direct Indirect
60. State Machines Applied: branching navigation
61. State Machines Applied: branching navigation Appointment Request
62. State Machines Applied: branching navigation Steps Appointment Request
63. State Machines Applied: branching navigation Steps Next Appointment Request
64. State Machines Applied: branching navigation Steps Next Embedded VCs Appointment Request
65. State Machines Applied: branching navigation Appointment Request
66. State Machines Applied: branching navigation Appointment Request
67. State Machines Applied: branching navigation Appointment Request
68. State Machines Whom Initial Whom Valid Direct Search Direct Search Valid Direct Chosen When Indirect Indirect Valid Direct Reason Direct Reason Valid Indirect Reason Indirect Reason Valid Applied: branching navigation
69. State Machines Whom Initial Whom Valid Direct Search When Indirect Applied: branching navigation
70. State Machines Whom Initial Whom Valid Direct Search When Indirect Applied: branching navigation
71. State Machines Whom Initial Whom Valid Direct Search When Indirect Applied: branching navigation
72. State Machines Whom Initial Whom Valid Direct Search When Indirect Applied: branching navigation
73. State Machines Whom Initial Whom Valid Direct Search When Indirect Applied: branching navigation
74. State Machines Whom Initial Whom Valid Direct Search When Indirect Applied: branching navigation
75. State Machines Applied: branching navigation Some time later…
76. State Machines Whom Initial Whom Valid Direct Search Direct Search Valid Direct Chosen When Indirect Indirect Valid Direct Reason Direct Reason Valid Indirect Reason Indirect Reason Valid Applied: branching navigation
77. State Machines Applied: branching navigation Initial When Indirect Indirect Valid Indirect Reason Indirect Reason Valid
78. State Machines Applied: session management
79. State Machines Applied: session management
80. State Machines Unauthent- icated Initial Manual PIN/ TouchID Preloading Running Expired Applied: session management
81. State Machines Applied: session management Unauthenti cated Initial Manual PIN/ TouchID Preloading Running Expired
82. State Machines Applied: session management Unauthenti cated Initial Manual PIN/ TouchID Preloading Running Expired
83. State Machines Applied: session management Unauthenti cated Initial Manual PIN/ TouchID Preloading Running Expired
84. State Machines Applied: session management Unauthenti cated Initial Manual PIN/ TouchID Preloading Running Expired
85. State Machines Applied: session management Unauthenti cated Initial Manual PIN/ TouchID Preloading Running Expired
86. State Machines Applied: session management Unauthenti cated Initial Manual PIN/ TouchID Preloading Running Expired
87. State Machines Applied: branching navigation Some time later…
88. State Machines Unauthent- icated Initial Manual PIN/ TouchID Preloading Running Expired Applied: session management
89. State Machines Unauthent- icated Initial Manual PIN/ TouchID Preloading Running Expired Applied: session management Web Token
90. State Machines Unauthent- icated Initial Manual PIN/ TouchID Preloading Running Expired Applied: session management Web Token
91. State Machines Unauthent- icated Initial Manual PIN/ TouchID Preloading Running Expired Applied: session management Web Token
92. State Machines Unauthent- icated Initial Manual PIN/ TouchID Preloading Running Expired Applied: session management Web Token
93. State Machines Unauthent- icated Initial Manual PIN/ TouchID Preloading Running Expired Applied: session management
94. In Closing
95. State Manage with intent
96. Ambiguous
97. BE OBVIOUS
98. Next Steps Topics to Google ➡ WWDC 2014, Session 232
 Advanced UI with CollectionViews ➡ Soroush Khanlou 
 khanlou.com
99. Thanks! @jaythrash jay@jaythrash.com http://jaythrash.com/talks