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Category Archive for ‘Recipes’ rss

Introducing Core Image

Barcodes with iOSI published a section from my book Barcodes with iOS on DZone. My book is not only about barcodes but also gives short introductions to a plethora of other frameworks which you might not normally come into contact with.

The Core Graphics framework is written in pure C, meaning that it’s impossible to use CGImage instances directly with UIKit. Apple created UIImage as an Objective-C wrapper class around CGImage to bridge the gap. We explore Core Image in this article.

My book currently available at a discount via the promo code mentioned on DZone.

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Skipping Copy Phase Strip

If your app contains frameworks or extensions you are recently beginning to notice a new warning popping up when building for releases: “skipping copy phase strip, binary is code signed”. Here’s how to fix it.

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Implementing an In-App App Store

If you have an app like, which shows a timeline of user’s messages you probably want interactive hyperlinks. In two previous posts I showed how I am customizing UILabel to customize hyperlinks drawing, as well as how to make them react to touches. For most links a UIWebView will do to show the content.

But not for content that people can purchase and/or download from iTunes or the Apple App Store. For this, there is SKStoreProductViewController. This post shows how to implement it.

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Making App Previews

Last year, at WWDC 2014, Apple presented a cool new way how we can show off our brilliant apps to an unsuspecting audience. After working on the official app for the better part of 3 months, today I created and published my first app preview video. Here’s how.

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Tappable UILabel Hyperlinks

In the previous blog post of this series, I have demonstrated how to modify the way UILabel draws hyperlinks. In this article I am showing how to implement function to make the hyperlinks tappable.

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Customizing UILabel Hyperlinks

For the ProductLayer app I wanted to show a timeline of user opines. Opines are – in spirit – similar to tweets and as such can also contain hyperlinks. In this post I am discussing how to customize hyperlink drawing for UILabels. In a second article on this subject I will then show how to implement tappable hyperlinks for UILabel as well.

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iPhone Downsizing

I admit it, I belong to the group of people who use their iPhone singlehandedly. That is, a single-thumb-typer. Also, I scoffed at the idea of a super-sized iPhone 6+. But I am somebody to apply the scientific method for examine the validity of your own beliefs. So I purchased and used an iPhone 6+ (Gold, 128 GB) for almost 2 months. Here’s my verdict as well as an intro do size classes.

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Dismissal Completion Handler

While working on an additional section for my book, I encountered a tricky situation. Pause for a moment and ponder how you would solve this: You present a modal view controller. Some action within it communicates via delegate to the presenting view controller and this dismisses it. You need to present a new modal view controller right after the first one has animated out.

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Development Pods

When integrating your own CocoaPods into your apps you often find some things you’d like to tweak in your component from within the app project/workspace. This would allow you to immediately test the fix in the context of the app. This blog explains how to work with Development Pods which allow you to do exactly that.

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Understanding OAuth 1.0a

Chapter 6 in my book deals with how to build a solid wrapper around a RESTful web service and how to unit-test it. I thought I had finished principal writing on my book when I handed in chapter 7, soon too appear in the Manning Early Access Program (MEAP) for readers who have preordered.

I walk you through implementing a wrapper – using NSURLSession – for searching for CDs on Discogs by scanned barcode. Until now the Discogs search API did not require any sort of authentication, which made it ideal for this example. Then a fateful email arrived on Friday, June 20th.

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