Localization is a great way to expand the potential customer base of your apps. Xcode makes it easy to add localization to an app, but what if you want to provide reusable localizations in a framework? You may be using the same strings in multiple apps or on multiple platforms, or you may be writing an open-source framework . . .
Wherever users can enter text in our apps, we usually need to respond to keyboard events. Adjusting our app's UI when the keyboard is shown and dismissed is necessary to maintain a good user experience. But what if we have multiple screens in our app that need to respond to keyboard events?
Almost every app we write needs to retrieve and serialize data from an API. Networking and serialization are not easy problems to solve, which is why open-source frameworks like Alamofire, Moya, and SwiftyJSON have been written to simplify this task. However, using URLSession and the new Codable protocol introduced in Swift 4 . . .
PDFKit has been available to Mac developers since 10.4, but with iOS 11 Apple brought its support for viewing, editing, and authoring PDFs to iPhone and iPad. Previously, viewing PDF files meant rendering each page yourself with Core Graphics and Core Text, using an indirect solution like UIWebView or QuickLook, or . . .
Most apps need to store sensitive user information at some point. Most commonly it's a service-specific credential like a password or authentication token, but it could also be an encryption key, expiration date, or really anything private to the user that shouldn't be easily accessible on the device.