HelsinkiOS21#January#2015

Useful'Code'Snippetsby#Jouni#Mie+unen#@jomtwi

Random'Color'(Theory)

Github:(Generate(a(random(color((UIColor)(in(Objec9ve;C

CGFloat h = ( arc4random() % 256 / 256.0 ); // 0.0 to 1.0CGFloat s = ( arc4random() % 128 / 256.0 ) + 0.5; // 0.5 away from whiteCGFloat b = ( arc4random() % 128 / 256.0 ) + 0.5; // 0.5 away from blackUIColor *c = [UIColor colorWithHue:h saturation:s brightness:b alpha:1];

• NSHipster:,How,Do,I,Generate,a,Random,Number,in,Objec<ve>C

• Julienne,Walker:,Using,rand()

Random'Color'(Code)- (UIColor *)randomColor{ // 0-255 to 0.0 - 1.0 CGFloat h = arc4random_uniform(256) / 255.f; // 0-127 to 0.5 - 1.0, away from white CGFloat s = arc4random_uniform(128) / 255.f + 0.5f; // 0-127 to 0.5 - 1.0, away from black CGFloat b = arc4random_uniform(128) / 255.f + 0.5f; return [UIColor colorWithHue:h saturation:s brightness:b alpha:1];}

Debug&at&Debug&(Theory)• StackOverflow:/How/to/print/out/the/method/name/and/line/

number/and/condi:onally/disable/NSLog?

• StackOverflow:/Why/isn't/ProjectNameEPrefix.pch/created/

automa:cally/in/Xcode/6?

• Github:/CocoaLumberjack:/A/fast/&/simple,/yet/powerful/&/

flexible/logging/framework/for/Mac/and/iOS

Debug&at&Debug&(Code)// DLog will output like NSLog only when DEBUG variable is set#ifdef DEBUG# define DLog(fmt, ...) NSLog((@"%s [Line %d] " fmt),\n __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__);#else# define DLog(...)#endif

// ALog will always output like NSLog#define ALog(fmt, ...) NSLog((@"%s [Line %d] " fmt),\n __PRETTY_FUNCTION__, __LINE__, ##__VA_ARGS__);

Who$Is$This$App$(Code)- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{ DLog(@"===== %@: %@ (%@)", [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleName"], [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleShortVersionString"], [[NSBundle mainBundle] objectForInfoDictionaryKey:@"CFBundleVersion"]);}

2015%01%20&23:36:30.891&Sample&App&ALPHA[96352:1016265]&%

[AppDelegate&applica>on:didFinishLaunchingWithOp>ons:]&[Line&

102]&=====&Sample&App&ALPHA:&2.1.2&(2411%task1364)

• 2411%task1364:-"number-of-git-commits"-%-"branch-name"

Who$Is$This$App$(Build$Script)

"Run%script%phase"%a/er%“Copy%Bundle%Resources”:# current branch name, to make collisions less likely across feature branches.

git=`sh /etc/profile; which git`appBuild=`"$git" rev-list --all |wc -l`if [ $CONFIGURATION = "Debug" ]; then branchName=`"$git" rev-parse --abbrev-ref HEAD` /usr/libexec/PlistBuddy -c "Set :CFBundleVersion $appBuild-$branchName" "${TARGET_BUILD_DIR}/${INFOPLIST_PATH}"else /usr/libexec/PlistBuddy -c "Set :CFBundleVersion $appBuild" "${TARGET_BUILD_DIR}/${INFOPLIST_PATH}"fi

Jared&Sinclair:&The&Best&of&All&Possible&Xcode&Automated&Build&Numbering&Techniques

Who$Is$This$App$(CI)

if [ -z $JENKINS_BUILD ]; then # Local build number is not set at jenkins CIfi

• Krzysztof*Zabłocki:*Overlaying*Applica;on*Version*On*Top*Of*Your*Icon

Main%Thread%Detector%(code)

Peter%Steipete:%Simple%main%thread%usage%detector%that%I'm%using%in%PSPDFKit%to%find%performance%problems%early%on.

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions{ // ... [PSPDFHangDetector startHangDetector]; // ...}

• Crash'when'UI'code'called'in'non2UI'thread

• No5fy'when'UI'thread'has'been'blocked'(0.5'sec)

Main%Thread%Detector%(code)@interface PSPDFHangDetector : NSObject+ (void)startHangDetector;@end

@implementation PSPDFHangDetector

+ (void)startHangDetector {#ifdef DEBUG NSThread *hangDetectionThread = [[NSThread alloc] initWithTarget:self selector:@selector(deadThreadMain) object:nil]; [hangDetectionThread start];#endif}

#ifdef DEBUGstatic volatile NSInteger DEAD_SIGNAL = 0;+ (void)deadThreadTick { if (DEAD_SIGNAL == 1) { NSLog(@"***** Main Thread doesn't answer *****"); } DEAD_SIGNAL = 1; dispatch_async(dispatch_get_main_queue(), ^{DEAD_SIGNAL = 0;});}

+ (void)deadThreadMain { [NSThread currentThread].name = @"PSPDFHangDetection"; @autoreleasepool { [NSTimer scheduledTimerWithTimeInterval:0.5 target:self selector:@selector(deadThreadTick) userInfo:nil repeats:YES]; [[NSRunLoop currentRunLoop] runUntilDate:[NSDate distantFuture]]; }}#endif

@end

No#fica#ons)(code)

Peter%Steipete:%Hook%onto%NSNo/fica/onCenter%to%see%all%no/fica/ons

[[NSNotificationCenter defaultCenter] addObserverForName:nil object:nil queue:nil usingBlock:^(NSNotification *note) { NSLog(@"%@: %@", note.name, note.userInfo); }];

Remember&NOT&to&use&NSLog()

Xcode&Code&Snippet&Library

__weak typeof(self) weakSelf = self;

__strong typeof(self) strongSelf = weakSelf;if (strongSelf){ <#code#>}

• NSHipster:,Xcode,Snippets

• Github:,Third7Party,Xcode,Snippets

Thank&You!Any$ques)ons?

Slides'will'be'available'via'SlideShare'by'Jouni'Mie2unen

@jomtwi