Slides from a talk about reducing the complexity in UIViewController classes for iOS using a pattern of smaller view coordinators

1. Avoiding oversized
view controllers
in iOS
Stewart Gleadow
Email:
sgleadow@thoughtworks.com
Twitter:
@stewgleadow

3. What makes a class
easy to maintain?

4. UIView
UIViewController
Model

6. What makes a
controller easy to
maintain?

9. UIViewController
- (id)init;
- (void)loadView;
- (void)viewDidLoad;
- (void)viewWillAppear:(BOOL);
- (void)viewDidAppear:(BOOL);
- (void)viewWillDisappear:(BOOL);
- (void)viewDidDisappear: (BOOL);
- (void)viewDidUnload;
- (void)dealloc;

10. UIViewController
- (id)init;
- (void)loadView;
- (void)viewDidLoad;
- (void)viewWillAppear:(BOOL);
- (void)viewDidAppear:(BOOL);
- (void)viewWillDisappear:(BOOL);
- (void)viewDidDisappear: (BOOL);
- (void)viewDidUnload;
- (void)dealloc;

11. UIViewController
- (id)init;
- (void)loadView;
- (void)viewDidLoad;
- (void)viewWillAppear:(BOOL);
- (void)viewDidAppear:(BOOL);
- (void)viewWillDisappear:(BOOL);
- (void)viewDidDisappear: (BOOL);
- (void)viewDidUnload;
- (void)dealloc;

13. - (id)init;
{
if ((self = [super init]))
{
// create data related objects
}
return self;
}
- (void)dealloc;
{
// release any data related objects
[super dealloc];
}

15. - (void)loadView;
{
[super loadView];
// create all your views
// assign delegates
}
- (void)viewDidUnload;
{
// release any view related
[super viewDidUnload];
}

17. @interface MatchViewController : UIViewController
<UITableViewDelegate,
UITableViewDataSource,
UIScrollViewDelegate,
TTModelDelegate,
...>

18. Coordinated Views
View One
View Two
View Three

19. Coordinator
- (id)init;
- (UIView *)view;
- (void)releaseView;
- (void)dealloc;

21. ViewController Coordinator
- (id)init; - (id)init;
- (void)loadView; - (UIView *)view;
- (void)viewDidLoad; - (void)releaseView;
- (void)viewWillAppear:(BOOL);
- (void)viewDidAppear:(BOOL); - (void)dealloc;
- (void)viewWillDisappear:(BOOL);
- (void)viewDidDisappear: (BOOL);
- (void)viewDidUnload;
- (void)dealloc;

22. ViewController Coordinator
- (id)init; - (id)init;
- (void)loadView; - (UIView *)view;
- (void)viewDidLoad; - (void)releaseView;
- (void)viewWillAppear:(BOOL);
- (void)viewDidAppear:(BOOL); - (void)dealloc;
- (void)viewWillDisappear:(BOOL);
- (void)viewDidDisappear: (BOOL);
- (void)viewDidUnload;
- (void)dealloc;

23. ViewController Coordinator
- (id)init; - (id)init;
- (void)loadView; - (UIView *)view;
- (void)viewDidLoad; - (void)releaseView;
- (void)viewWillAppear:(BOOL);
- (void)viewDidAppear:(BOOL); - (void)dealloc;
- (void)viewWillDisappear:(BOOL);
- (void)viewDidDisappear: (BOOL);
- (void)viewDidUnload;
- (void)dealloc;

24. Demo

25. Stewart Gleadow
Email:
sgleadow@thoughtworks.com
Twitter:
@stewgleadow