Articles about iOS development in Swift or Objective-C
Sometimes you may find it useful to transfer an existing app you deployed on a particular simulator, to another simulator without having to build and run the app again in Xcode. The main scenario I have in mind is during beta time, when you want to check how an existing app, built with the current
Sometimes you may need to display HTML content in your app, even if you don’t use a framework to make hybrid apps. Usually you can just open the mobile version of your website to show a particular page, but what if your app need to work offline? Turns out it is still a requirement, even
This post is about a couple of project I put on GitHub to implement authentication via biometric (FaceID or TouchID on the iPhone) and to save login information on the KeyChain. I wanted to have some fun with SwiftUI so I implemented a custom keypad to enter a PIN, with a button to invoke biometric
In this article I’ll show you how to integrate ARKit in a SwiftUI app. With this simple app, you’ll be able to tap on two points of the AR scene and calculate the distance between them. As usual, the code is available on GitHub. ARKit view Let’s start with ARKit. The example is quite simple,
UPDATE: WWDC21 introduced refreshable, a view modifier to implement pull to refresh in a List, see the example at the end. This article is still valid if you want to target iOS 13 and 14 as the new modifier is only iOS 15 compatible. Pull down to refresh a list is something quite common for
I’ve written about CoreML and Vision in the past and this time I decided to use both of them to perform object recognition in images in a simple iOS app. You can find the post about Vision at this link, in the example I used Vision to perform barcode detection and OCR. My first post
This article is about an app I decided to make in order to play with CoreML and SwiftUI. I wanted to make a reader for RSS feeds, and I though it would be a good idea to include a model to automatically label the entries of the feed. The app, and the playground I used
Today I felt like experimenting with ARKit and I couldn’t figure out a sample project to start with. When I want to start exploring a new framework or a new API, my approach is usually to start with something simple, but starting with an actual use case.So I though, what about a video player that
If you follow me you know I like sharing code on GitHub and distribute small utilities via Swift Package Manager (by the way this is my article about SPM).Sometimes though, we cannot share our source code and need our customers to integrate our package. We can’t share the code via SPM, so we need to
In this post I’m going to show you how I implemented OCR, both on an image or live from the camera feed, by using Vision, and I’ll use the same view controller to perform live scan of barcodes. I already wrote about barcodes in the past so I won’t go into details about that part
Inspired by an episode of ATP and by this blog post by Alex Chan I decided to write a simple app to find out which lenses I use the most on my iPhone.The post linked above teach you how to use exiftool, and if you have your photo library on the Mac this is a great option.But what if
Nowadays, we take for granted that our phones are always connected to the internet, it may be WiFi, 4G or even 5G if you have an iPhone 12 🙂Being offline is not something that happens too frequently, but it is a possibility. While we can always show an error message, it can be nice to
This article is about one of the new features of iOS 14: Widgets. I’ll show you how to write a simple widget in SwiftUI, and how to update the widget data from your iOS app.As usual, all the code is available on GitHub. Intro What is a Widget? Is an extension to your app, showing
This article is about one of welcome additions to SwiftUI in 2020: LazyVGrid and LazyHGrid. As the name suggest, you can compose vertical and horizontal grid layout in a lazy way with those views. If you’re interested in lazy layout, check out my previous article on the topic. The sample project In this article I’ll
SwiftUI introduced from the very beginning the components HStack and VStack to group views in an horizontal or vertical stack. Those components load all their children up front, so they’re not suitable for implementing a long list of items, as you’d rather have lazy loading.One alternative was using the List component, which implements lazy loading,
This article is about some news in SwiftUI app cycle. With the second release of SwiftUI, is finally possible to make an app entirely in SwiftUI, without having to embed it in UIKit or AppKit on the Mac. We’ll see how to create a SwiftUI only app, manage independent Scenes and share data between them.As
This post is about enhancements in Function Builders in Swift 5.3. I wrote two articles about Function Builders in the past so you may want to check them out before continuing with this one. Introduction to Function BuildersCreate a DSL with Function Builders UPDATE: the feature finally made it to the language and is now
As you know if you follow me I have many hybrid apps, with native code and web content. Recently I encountered a problem: I needed to show a web page and download a file from it. As most developer do these days, I looked for this very post title on Google, and I couldn’t find
I like the fact that Apple takes accessibility quite seriously. We have talks during WWDC, and tools like the Accessibility Inspector to help us test and audit our apps.In this article I’ll show you how to write your CSS in order to support dynamic fonts in iOS, so when your user changes the preferred font
Using lists is very common in an iOS app. UITableViews are great and have been there from the very beginning, so you can find tons of articles about infinite scrolling. But what about SwiftUI?You don’t have UITableView, but you can use List. Although you can achieve a similar result you don’t have the concept of
I’ve written another article about Function builders so you may want to have a quick read to that as well. The example I used in the article is really simple, but I go into more details about Function Builders. UPDATE: the feature finally made it to the language and is now called Result Builders. You
Swift Package Manager is a tool for helping distributing Swift code and has been around since Swift 3, but with Xcode 11 Apple finally integrated it into the IDE we all use to make iOS apps so it is easier than ever to adopt SPM.In this article I’ll talk about how to integrate packages distributed
One of the new features of Xcode 11 is the ability to see a live preview of a SwiftUI view in what is called the Canvas. This is really convenient while working with a UI as you can modify the code and have an immediate feedback about the result.Wouldn’t it be cool to have a
One of the things I like about iOS development is that the latest version of the operating system has usually a very good adoption rate, but iOS 13 doesn’t support a pretty popular model like iPhone 6 and sometimes your customers need to use older devices, I still have to support iOS 9 so devices
Sometimes you need to share code between iOS and Android, or you have business logic for a customer already written in JavaScript because it is used on the web.If you need to run JavaScript code on your app loading a page into a WkWebView is one of your options and you can read my previous
As you probably know UIWebView has been deprecated in iOS 13, I’ve use it in my projects for years and it was really convenient to display HTML pages inside an app but even to interact with Javascript, for example to perform operations on JSON files sharing the same login with Android and even with the
Back in July I wrote a post about Navigation in SwiftUI trying to explain the difference between NavigationLink and DynamicNavigationDestinationLink. The latter has been deprecated, so the article is now useless, you can still find it here https://www.gfrigerio.com/navigation-in-swiftui-deprecated/I updated the repository on GitHub to remove the deprecated code and provide a few examples of various
Almost every iOS app needs to display images, you can have them in your app’s bundle or you load them from an external URL, and that’s what this article is all about.As usual you can find the source code on GitHub at this link Building the UI In the example I’m presenting a list of
WWDC 2019 was really packed with new stuff for iOS and the new data sources for TableViews and CollectionViews didn’t get the same attention as SwiftUI but are a really nice addition for people still working with UIKit. I’m going to focus my post on UITableViewDiffableDataSource but there is a similar API for CollectionViews and
If you are a registered developer Apple sent you an email reminding you to update your app to implement Dark Mode. There is a WWDC session dedicated to that, this post is a quick introduction to the topic with an example on how to implement a theme manager in your app. I think it is
One of the topics I wanted to explore about SwiftUI was how to integrate CoreData in it, and I want to describe two approaches you can follow: a direct one using property wrappers and another one by having a class hide the existence of Core Data to the user.I usually prefer the latter, as it
If you came across this blog post and you’re happy because you didn’t think it was possible to use NSAttributedString in SwiftUI I have a bad news: it isn’t supported yet. Text in SwiftUI accept a String and there isn’t the equivalent of attributedText you can find in UILabel. So what is this article about?
Progress bars and activity indicators is something we tend to use a lot in iOS applications and it is nice to customise them instead of using all the time the standard UIActivityIndicatorView.I think SwiftUI makes it really easy to build this kind of views and I implemented 4 of them in my sample GitHub project
UPDATE: DynamicNavigationDestinationLink has been deprecated so most of this article is useless. I wrote a new one and updated the GitHub repository In this post I want to explain the difference between NavigationLink and DynamicNavigationDestinationLink in SwiftUI with a quick example and point out the differences between them.You can find the sample code on GitHub
SwiftUI was one of my favourite announcements during WWDC 2019 alongside Combine. At the time I’m writing this post, mid July, beta 4 has just been released and although it isn’t yet stable I think SwiftUI is starting to get interesting. I think it will be hard to drop iOS 12 support soon, but SwiftUI
I want to share my experience building and distributing apps with xcodebuild hoping to help some iOS developer struggling with automating build and distribution via command line. There are two ways to distribute a test version of your app for iOS: TestFlight and Ad Hoc.The former allows you to submit a build to App Store
Here’s a quick guide to implement Push notifications on iOS. Every now and then I need to implement push notification and I always forget how to create the certificate and convert it to use with python, so this guide will be helpful to the future myself and hopefully to some fellow developers 😉Actually, creating the