Roman Efimov romaonthego

Howdy howdy, NSHipsters!

If you alloc init an NSCalendar, you'll notice that New Year's Eve falls on a Monday this year, a.k.a. "the day NSHipster is published every week". What fun!

So in celebration of the upcoming year++, I thought it'd be fun to compile a list of some of your favorite tips and tricks of the trade. Submit your favorite piece of Objective-C trivia, framework arcana, hidden Xcode feature, or anything else you think is cool, and you could have it featured in the year-end blowout article. Just comment on this gist below!

Here are a few examples of the kind of things I'd like to see:

StaticObjcMethods from [Apple]((http://developer.apple.com/library/mac/#samplecode/CocoaTipsAndTricks/Introduction/Intro.html): Demonstrates how to use static Objective-C m

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

Hacking UIView animation blocks for fun and profit

In this article, I'm going to explore a way that we can create views that implement custom Core Animation property animations in a natural way.

As we know, layers in iOS come in two flavours: Backing layers and hosted layers. The only difference between them is that the view acts as the layer delegate for its backing layer, but not for any hosted sublayers.

In order to implement the UIView transactional animation blocks, UIView disables all animations by default and then re-enables them individually as required. It does this using the actionForLayer:forKey: method.

Somewhat strangely, UIView doesn't enable animations for every property that CALayer does by default. A notable example is the layer.contents property, which is animatable by default for a hosted layer, but cannot be animated using a UIView animation block.

	// Usage example:
	// input image: http://f.cl.ly/items/3v0S3w2B3N0p3e0I082d/Image%202011.07.22%2011:29:25%20PM.png
	//
	// UIImage *buttonImage = [UIImage ipMaskedImageNamed:@"UIButtonBarAction.png" color:[UIColor redColor]];

	// .h
	@interface UIImage (IPImageUtils)
	+ (UIImage )ipMaskedImageNamed:(NSString )name color:(UIColor *)color;
	@end

	// clang -framework Foundation -fobjc-arc -O3 test.m

	#import <Foundation/Foundation.h>


	@interface Slice : NSObject
	@property NSInteger start;
	@property NSInteger length;
	@end
	@implementation Slice

	// Taken from http://PSPDFKit.com. This snippet is under public domain.
	#define UIKitVersionNumber_iOS_7_0 0xB57
	BOOL PSPDFIsUIKitFlatMode(void) {
	static BOOL isUIKitFlatMode = NO;
	static dispatch_once_t onceToken;
	dispatch_once(&onceToken, ^{
	// We get the modern UIKit if system is running >= iOS 7 and we were linked with >= SDK 7.
	if (kCFCoreFoundationVersionNumber >= kCFCoreFoundationVersionNumber_iOS_7_0) {
	isUIKitFlatMode = (NSVersionOfLinkTimeLibrary("UIKit") >> 16) >= UIKitVersionNumber_iOS_7_0;
	}

	typedef enum _UIBackgroundStyle {
	UIBackgroundStyleDefault,
	UIBackgroundStyleTransparent,
	UIBackgroundStyleLightBlur,
	UIBackgroundStyleDarkBlur,
	UIBackgroundStyleDarkTranslucent
	} UIBackgroundStyle;

	@interface UIApplication (UIBackgroundStyle)
	-(void)_setBackgroundStyle:(UIBackgroundStyle)style;

	<?xml version="1.0" encoding="UTF-8"?>
	<Bucket
	type = "2"
	version = "2.0">
	<Breakpoints>
	<BreakpointProxy
	BreakpointExtensionID = "Xcode.Breakpoint.SymbolicBreakpoint">
	<BreakpointContent
	shouldBeEnabled = "Yes"
	ignoreCount = "0"

	extension Array {

	func first() -> Element? {
	if isEmpty {
	return nil
	}
	return self[0]
	}

	func last() -> Element? {

	//
	// UIApplication+UDCStatusView.m
	// Udacity
	//
	// Created by Oliver Cameron on 12/5/13.
	// Copyright (c) 2013 Udacity. All rights reserved.
	//

	#import "UIApplication+UDCStatusView.h"