Upgrade to Pro
— share decks privately, control downloads, hide ads and more …
Speaker Deck
Features
Speaker Deck
PRO
Sign in
Sign up for free
Search
Search
Cocoa Touch: The Good, The Bad and The Ugly
Search
Chris Eidhof | @chriseidhof
December 16, 2013
Programming
2
190
Cocoa Touch: The Good, The Bad and The Ugly
This is a talk I gave at Alt Tech Talks London, as a try out for MCE.
Chris Eidhof | @chriseidhof
December 16, 2013
Tweet
Share
More Decks by Chris Eidhof | @chriseidhof
See All by Chris Eidhof | @chriseidhof
Dutch FP Day 2015
chriseidhof
2
380
Tiny Networking in Swift
chriseidhof
2
19k
Functional Swift - Brooklyn
chriseidhof
3
1.2k
Functional Swift - SF
chriseidhof
6
26k
Functional Swift
chriseidhof
6
1.3k
Functional Swift
chriseidhof
1
140
Functional Programming in Swift
chriseidhof
40
19k
Lighter View Controllers
chriseidhof
4
190
Parsing with Blocks
chriseidhof
2
230
Other Decks in Programming
See All in Programming
Rails産でないDBを Railsに引っ越すHACK - Omotesando.rb #110
lnit
1
100
What Spring Developers Should Know About Jakarta EE
ivargrimstad
1
620
技術懸念に立ち向かい 法改正を穏便に乗り切った話
pop_cashew
0
830
テスト分析入門/Test Analysis Tutorial
goyoki
12
2.7k
Agent Rules as Domain Parser
yodakeisuke
1
350
漸進。
ssssota
0
1.2k
MLOps Japan 勉強会 #52 - 特徴量を言語を越えて一貫して管理する, 『特徴量ドリブン』な MLOps の実現への試み
taniiicom
2
570
技術的負債と戦略的に戦わざるを得ない場合のオブザーバビリティ活用術 / Leveraging Observability When Strategically Dealing with Technical Debt
yoshiyoshifujii
0
160
Doma で目指す ORM 最適解
nakamura_to
1
160
AIにコードを生成するコードを作らせて、再現性を担保しよう! / Let AI generate code to ensure reproducibility
yamachu
7
6.1k
マテリアルって何者?RealityKitで扱うマテリアル入門
nao_randd
0
140
複数アプリケーションを育てていくための共通化戦略
irof
3
760
Featured
See All Featured
The Psychology of Web Performance [Beyond Tellerrand 2023]
tammyeverts
47
2.8k
Done Done
chrislema
184
16k
Facilitating Awesome Meetings
lara
54
6.4k
The Art of Delivering Value - GDevCon NA Keynote
reverentgeek
14
1.5k
Music & Morning Musume
bryan
47
6.6k
Writing Fast Ruby
sferik
628
61k
GitHub's CSS Performance
jonrohan
1031
460k
The Pragmatic Product Professional
lauravandoore
35
6.7k
The Straight Up "How To Draw Better" Workshop
denniskardys
233
140k
The Illustrated Children's Guide to Kubernetes
chrisshort
48
50k
CSS Pre-Processors: Stylus, Less & Sass
bermonpainter
357
30k
10 Git Anti Patterns You Should be Aware of
lemiorhan
PRO
656
60k
Transcript
None
Cocoa Touch The Good, The Bad and The Ugly Chris
Eidhof
Cocoa Touch The Ugly, The Good and The Bad Chris
Eidhof
commit c416c1d259bddaa74833e6df5acd770f85622293 Author: Chris Eidhof <
[email protected]
> Date: Wed Jan 7
11:54:34 2009 +0100 Empty project
None
None
I thought I was a pretty good programmer
I knew PHP, Ruby and Haskell
How hard can it be?
None
The ugly
Example code @interface HiscoreTableViewCell : UITableViewCell { IBOutlet UIImageView *badge;
IBOutlet UILabel *badgeTitle; IBOutlet UILabel *name1; IBOutlet UILabel *name2; IBOutlet UILabel *name3; IBOutlet UILabel *position1; IBOutlet UILabel *position2; IBOutlet UILabel *position3; IBOutlet UILabel *score1; IBOutlet UILabel *score2; IBOutlet UILabel *score3; }
Example code (continued) @property (nonatomic,readonly) UIImageView* badge; @property (nonatomic,readonly) UILabel
*badgeTitle; @property (nonatomic,readonly) UILabel *name1; @property (nonatomic,readonly) UILabel *name2; @property (nonatomic,readonly) UILabel *name3; @property (nonatomic,readonly) UILabel *position1; @property (nonatomic,readonly) UILabel *position2; @property (nonatomic,readonly) UILabel *position3; @property (nonatomic,readonly) UILabel *score1; @property (nonatomic,readonly) UILabel *score2; @property (nonatomic,readonly) UILabel *score3;
Example code (continued) @synthesize badge; @synthesize badgeTitle; @synthesize name1; @synthesize
name2; @synthesize name3; @synthesize position1; @synthesize position2; @synthesize position3; @synthesize score1; @synthesize score2; @synthesize score3;
There's more
//TODO: as of here, it is completely broken if ([gameView
superview] != nil) { [[SoundBoard sharedSoundBoard] startMenuTune]; [menuViewController viewWillAppear:YES]; [gameViewController viewWillDisappear:YES]; [gameView removeFromSuperview]; [gameViewController viewDidDisappear:YES]; [menuViewController viewDidAppear:YES]; } else {
NSURL *cgiUrl = [NSURL URLWithString:POST_SCORE_URL]; NSMutableURLRequest *p = [NSMutableURLRequest requestWithURL:cgiUrl];
[p setTimeoutInterval:4]; [p setHTTPMethod:@"POST"]; [p setHTTPBody:requestData]; NSURLResponse *response = nil; NSError *error = nil; NSData *responseData = [NSURLConnection sendSynchronousRequest:p returningResponse:&response error:&error];
Memory Management 1. Add an instance variable 2. Add a
property 3. Add a synthesize 4. Add a dealloc call
Memory Management 1. Add an instance variable 2. Add a
property 3. Add a synthesize 4. Add a dealloc call
Memory Management
Animations [UIView beginAnimations:@"GameOver" context:NULL]; [UIView setAnimationDuration:0.3]; [UIView setAnimationRepeatCount:2]; [UIView setAnimationRepeatAutoreverses:YES];
// Call animateOtherStuff when the animation is done [UIView setAnimationDelegate:self]; [UIView setAnimationDidStopSelector: @selector(afterGameOverAnimation:finished:context:)];
Animations 2013 [UIView animateWithDuration:0.3 animations:^{ timesUp.alpha = 1; } completion:^(BOOL
finished) { [self.milkGlass removeFromSuperview]; }]
None
The Good
If there's only one thing you'll remember Write code for
the person after you
▸ Write a lot of code ▸ Work with other
people ▸ Write articles ▸ Read books and code
Write a lot of code ▸ Lots of production code
▸ Lots of throwaway code
Throwaway code
Collaborate ▸ With people who are better than you ▸
Or who aren't better than you
Write Forces you to think.
Absolute Knowledge
Perceived Knowledge
Strive to become better
Ship
Frameworks
2013 ▸ Use ARC ▸ Use properties
Core Data
What prevents me from using Core Data at this point
is my concern for scalability and performance. It’s possible I’m just being thick-headed. — Brent Simmons, 27 Sep 2013
So last weekend I switched from SQLite/FMDB to Core Data.
This may come as a surprise. — Brent Simmons, 05 Oct 2013
None
Core Data ▸ Relationships ▸ Batching ▸ NSFetchedResultsControlle r ▸
Speed of use
Code style
My model was the NSURLConnectionDelegate Model should not know about
the webservice
Using NSDictionary everywhere Create value objects
Value Objects @interface Person : NSObject @property (nonatomic,copy,readonly) NSString* name;
@property (nonatomic,strong,readonly) NSDate* birthDate; @property (nonatomic,readonly) NSUInteger numberOfKids; - (instancetype)initWithName:(NSString*)name birthDate:(NSDate*)birthDate numberOfKids:(NSUInteger)numberOfKids; @end
Immutable Objects Use lots of them.
Deep code paths - (void)alertView:(UIAlertView *)alertView didDismissWithButtonIndex:(NSInteger)buttonIndex { if (alertState
== submitScore && game.score > 0) { // 20 lines if (result != nil && [resultKeys containsObject:@"position"] && [resultKeys containsObject:@"neededPoints"] && [resultKeys containsObject:@"deviceHighscore"] && [resultKeys containsObject:@"personalHighscore"]) { // 10 lines if (position == 1) {
Deep code paths Pull out things into separate, well-named methods
Building everything in code Use Interface Builder
Writing fast code Write clear code, only optimize after measuring.
None
Tips and Tricks
Initializers [[HiscoresViewController alloc] initWithNibName:@"HiscoresView" bundle:nil]
Initializers // In HiscoresViewController.m - (id)init { self = [super
initWithNibName:@"HiscoresView" bundle:nil]; if (self) { } return self; }
Use constants if (buttonIndex == 0)
Use constants if (buttonIndex == StartButton)
Pull out variable names if ([game state] == running ||
self.trainingMode)
Pull out variable names BOOL shouldPauseGame = [game state] ==
running || self.trainingMode; if (shouldPauseGame)
Pulling out protocols For example: UITableViewDataSource
@interface FetchedResultsControllerDataSource : NSObject <UITableViewDataSource, NSFetchedResultsControllerDelegate>
- (NSInteger)numberOfSectionsInTableView:(UITableView*)t { return self.fetchedResultsController.sections.count; }
- (NSInteger)tableView:(UITableView*)tableView numberOfRowsInSection:(NSInteger)sectionIndex { id<NSFetchedResultsSectionInfo> section; section = self.frc.sections[sectionIndex]; return
section.numberOfObjects; }
- (UITableViewCell*)tableView:(UITableView*)tableView cellForRowAtIndexPath:(NSIndexPath*)ip { id object = [self objectAtIndexPath:indexPath]; id
cell = [tableView dequeueReusableCellWithIdentifier:ruI forIndexPath:ip]; [self.delegate configureCell:cell withObject:object]; return cell; }
Write small files I aim for a 100 line limit
Write small files 154 ./ViewControllers/THUserPrioritiesViewController.m 154 ./ViewControllers/THZoomingNavigationController.m 155 ./Extensions/NSArray+Extensions.m 155
./Extensions/UIView+Extensions.m 168 ./Controllers/THPriorityTimelineCollectionController.m 179 ./Controllers/THUserScreenInstancesController.m 183 ./ViewControllers/THRootViewController.m 183 ./ViewControllers/THScreenInstanceViewController.m 185 ./Model/User+Extensions.m 192 ./ViewControllers/THEditPriorityViewController.m 221 ./ViewControllers/THScreeningBarViewController.m 243 ./Views/THTimeLineView.m 263 ./ViewControllers/THCardsViewController.m 279 ./Views/THSkillboxView.m
Write small files find . -name "*.m" -exec wc -l
"{}" \; | sort -n
Keep your view controllers light This is the least reusable
code you'll write
Use protocols instead of inheritance
None
The Bad
None
None
About me ▸ @chriseidhof ▸ http://www.objc.io ▸ http://chris.eidhof.nl
Questions?