For a tvOS app I needed to efficiently group by a certain column and then count the resulting rows or sum the value. And since I do everything in Swift 3 these days, I couldn’t find any suitable example on line. But I eventually figured it out.
Category Archive for ‘Recipes’ 
Firebase Tutorial
Since the official Parse shutdown, many people are looking for alternatives. Google established Firebase as one such option for your web-based backend. In this tutorial we will be exploring how to build an iOS app that uses Google Firebase as backend.
iTunes Connect Encryption Info
Apps on Apple’s App Store are technically originating in the US. Therefore they are affected by US rules governing the export of encryption technology. For a long while, I remember, Apple asked developers during app submission if the app was using encryption.
Asynchronous NSTextAttachments (2/2)
In the first part of this two-part blog post, you saw how NSAttributedString works with remote images when parsing HTML, namely synchronously downloading them. I teased that I found a way to have NSTextAttachment also work asynchronously. In this second part I will walk you through how this is achieved.
Asynchronous NSTextAttachments (1/2)
In iOS 7, Apple introduced the NSTextAttachment class for embedding images into attributed strings. OS X, pardon macOS, did have this feature much earlier, already as early as 2001 in version 10.0 “Cheetah”. I suspect that they needed 7 years to migrate because the first needed to revamp the inner workings of UITextView and UITextField to natively work with attributed text, as well as modernize CoreText into what is nowadays referred to as TextKit.
With iOS 10 being released, we now have 3 major iOS releases supporting text attachment in standard UIKit views. About time, that we start using text attachments for displaying inline images in rich text.
An Update on Custom Modal Presentations
Customizing a modal presentation of a view controller would be tricky before iOS 7. It got much easier with the addition of the transitioningDelegate protocol. This delegate would be able to vend an animation controller and an interaction controller for presentation and dismissal on the view controller which implemented them.
Without that, if you wanted a “burger menu” then you had to implement a custom container controller like I did with DTSidePanel in DTFoundation 1.4, three years ago. Things have gotten much easier a year ago.
A client of ours liked the way the Linked In app showed related apps in a modal side panel and so I went to research how you would that most reusably nowadays.
App-Level Passcode
In the latest version of iWoman we are finally coming around to implementing TouchID. Or more precisely: device owner authentication.
iOS 8 introduced the ability to let us use the user’s finger print for authentication. But if that wasn’t set up or otherwise unavailable, we still had to fall back to displaying a keypad via DTPinLock. iOS 9 finally gave us the ability to fall back on the device passcode, just like the user would use to unlock iPhone without TouchID.
Swift Golf
For a project I needed a way to get a reference to a UISwitch contained in the contentView of a UITableViewCell. I remembered from my research for my Swift talk that there was this handy is operator, so I was excited to tweet that I had finally found the first good use for it.
