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Make SF Symbols and custom images adapt to different font sizes while maintaining layout balance, keeping key icons clear, and providing more space for higher-priority content when needed.

Learn how to define custom environment values in SwiftUI, eliminate boilerplate with the @Entry macro in Xcode 16, and pass data through the view hierarchy efficiently.

Set a custom background, like an image or a translucent material, for SwiftUI sheets, popovers, and full-screen covers, and explicitly control the presentation color scheme.

Implement a high-performance lazy scrolling list in SwiftUI by efficiently reusing views for smooth scrolling with large datasets.

Detect window focus with the appearsActive environment value to adjust UI and handle focus changes.

It’s already the end of February, which means it’s time for the second issue of this newsletter! We’ve been enjoying the last days of summer here in New Zealand, and it has been a busy month for us at Nil Coalescing. The biggest news this month is the release of my new book - "SwiftUI Fundamentals".

"SwiftUI Fundamentals" is a new book by Natalia Panferova that explores SwiftUI’s core principles and APIs in depth. It will help you build a solid foundation for using SwiftUI effectively in your projects.

Learn how to build a macOS menu bar app in SwiftUI using MenuBarExtra, customize its icon, hide it from the Dock, and add essential features like a quit option.

Verify SwiftUI app state restoration using the Xcode simulator by following the correct steps, including backgrounding the app and relaunching it.

Build reusable, type-safe components for extracting and validating UUID values using Swift's RegexBuilder framework.

Welcome to the very first issue of this newsletter, I’m so excited to have you on board! In this newsletter, I’ll be sharing updates from our small team at Nil Coalescing, cool projects we’ve worked on, interesting technical learnings, blog posts, and special discounts on my Swift and SwiftUI books, exclusively for newsletter subscribers.

Handle multiple concurrent WebSocket messages per connection with Django Channels.

Extend your app’s functionality to the entire macOS system by implementing services that users can access from the context menu or the Services menu in other apps.

Starting with iOS 16.4, we can use the presentationCompactAdaptation(_:) modifier to tell SwiftUI that we prefer popover presentation even in compact size classes.

Register your macOS app as a login item using SMAppService.

Display grammatically correct text effortlessly with Foundation's automatic grammar agreement, handling pluralization without extra logic.

Learn how to add Codable conformance to Swift enums, including automatic synthesis, customizations, and fully manual implementations for complex cases.

Apply a translucent background to macOS windows using SwiftUI APIs, and adjust the toolbar background and title visibility to customize the window's appearance.

Lighten or darken colors in SwiftUI views using the brightness(_:) modifier.

Explore noncopyable types in Swift and learn how they enforce stricter ownership rules to avoid unintended errors and resource conflicts.

To copy a string to the clipboard on macOS, we need to first clear it using clearContents(), unlike on iOS, where UIPasteboard automatically overwrites the existing data.

SwiftUI provides a simple way to set a view's background to a shape, like a capsule or rounded rectangle, using the background(_:in:fillStyle:) modifier.

Learn how to use matchedGeometryEffect() in SwiftUI to animate a capsule background that highlights the selected option in a custom segmented control.

With iOS 18, we can now use SwiftUI animations to animate UIKit views, making it easier to bring SwiftUI’s expressive and flexible animations into UIKit projects.

Configure a file target membership in Xcode to restrict it to specific platforms, avoiding the need for conditional compilation checks when the file contains platform-specific code.

Learn how to resolve the issue of using lazy variables in @Observable classes by annotating them with @ObservationIgnored.

Xcode 16 introduced the @Previewable macro, making it easier to preview SwiftUI views with bindings.

"Integrating SwiftUI into UIKit Apps" by Natalia Panferova has been updated, featuring the latest tools like Observable, the Preview macro, and a new section on animating UIKit views with SwiftUI animations in iOS 18.

Font modifiers in SwiftUI let us style text directly at the font level, offering precise control over typography in our apps.

Use localizedStandardRange(of:) in Swift for flexible, locale-aware, case and accent-insensitive string searches, providing a user experience similar to system-wide searches.

Explore different ways to work with SwiftUI environment, including reading and setting values, creating custom environment keys, and using the environment to pass down actions and observable classes.

Sorting arrays in Swift can be made more concise and readable by using comparison operators as closures in the sorted(by:) method.

Discover how to use the @Observable macro in SwiftUI and its advantages over ObservableObject, such as more efficient view updates and simplified code management.

This post explains how to use recursive enums in Swift, including the indirect keyword, to effectively model and manage complex, hierarchical data structures.

A simple method for rendering quadratic Bézier curves on the GPU in Metal without pre-processing geometry.

Efficiently count the number of elements in a sequence that satisfy the given condition with the new count(where:) method introduced in Swift 6.

Learn how to adjust size, color, rendering modes, variable values, and design variants of SF Symbols in SwiftUI apps.

Discover Strolly, our new free app that generates unique daily walking routes, providing variety and adventure while keeping user privacy in mind.

Using the overlay() modifier in SwiftUI, we can elegantly wrap text within another view, ensuring the text is positioned and sized relative to the primary content.

SwiftUI custom scenes enable the creation of modular, maintainable code, allowing for precise management of complex user interfaces and behavior across different platforms.

Leverage the new magic replace symbol effect in iOS 18 for smooth transitions of slashes and badges in SF Symbols.

Sheet sizing became more flexible in SwiftUI on iPadOS 18, with the default size now matching a form sheet and presentationSizing() allowing explicit size customizations.

Take advantage of the new macOS 15 API to update SwiftUI views when modifier keys are pressed.

Learn how to use MapKit and SwiftUI to apply a gradient that follows a polyline, enhancing the visual appeal of your maps.

When we need to compare arrays based on custom criteria in Swift, we can use elementsEqual(_:by:) method. It allows us to define custom comparison logic with a closure, offering more flexibility than using == operator.

Discover how to leverage SwiftUI's versatile scene types, like WindowGroup, DocumentGroup, Settings, Window, and MenuBarExtra, to create efficient and dynamic macOS applications.

Use convertFromSnakeCase in JSONDecoder to automatically map JSON snake case keys to Swift camel case properties, simplifying model definitions and ensuring naming consistency.

I recently gave a talk at Code Camp Wellington on how starting a technical blog can transform your career development. Since it wasn't recorded, I've summarized my insights in this post to inspire others to share their technical knowledge online.

Learn how to use NWPathMonitor as an async sequence for real-time network status updates in your SwiftUI views.

Swift's tuples are a convenient way to group multiple values, and their true utility shines with the language's built-in ability to compare tuples.

"Swift Gems" is a new book by Natalia Panferova for seasoned Swift developers. It offers over 100 tips and techniques to improve code efficiency and robustness, ideal for those looking to advance their Swift expertise.

By taking advantage of provisional authorization for notifications, we can provide a gentle introduction to our app's notifications without upfront permission from the user.

Guide users through resolving issues and make your Swift applications more intuitive and supportive by defining user-friendly descriptions and recovery suggestions for custom errors.

Explore the practical applications and distinctions of self, Self, and Self.self in Swift, clarifying their roles in instance referencing, protocol conformance, and metatype access.

Discover how string comparison methods from Foundation outperform basic case conversion, ensuring precise, efficient, and culturally aware comparisons in our applications.

Define custom logic for matching different types of data in switch cases by overloading the Swift pattern matching operator (~=).

Property observers like willSet and didSet aren't triggered during initialization in Swift, but if we need to execute logic from property observers at this stage, we can use some workarounds.

Learn how to wrap withObservationTracking() into an AsyncStream to iterate over changes with an async for loop.

Monitor changes to specific properties of an observable class using withObservationTracking() function from Observation framework in iOS 17.

Use the new instance properties of the ShapeStyle in iOS 17 to access hierarchical system background styles, such as secondary and tertiary background.

Take advantage of the new improvements in the debug console in Xcode and learn how to filter logs by type, category or message, show and hide similar items and view log metadata.

This post will walk you through all the necessary setup so that you can enable remote push notification functionality in your iOS project.

Add icons to buttons in actionable push notifications using the UNNotificationActionIcon class to make notifications more intuitive and visually appealing.

Add custom foreground styles such as gradients to words inside Text view in SwiftUI in iOS 17.

In Xcode 15 code completion we can view all the possible permutations of function parameters by pressing the right arrow key.

The focusable() modifier now available on iPadOS 17 allows us to provide full keyboard navigation, even including custom views not focusable by default.

Starting from iOS 17 and iPadOS 17 we can now use ControlGroup to display a horizontal collection of actions in a context menu.

Swift 5.9 introduces the use of if/else statements as expressions, simplifying value returns, variable assignments, and enhancing code readability.

Xcode 15 automatically generates static properties on ColorResource and ImageResource types for colors and images that we store in asset catalog. This lets us access them in SwiftUI, UIKit or AppKit code without using string literals.

Let's look into the new inspector() presentation API in iOS 17, iPadOS 17 and macOS 14 and see how to customise its width on iPad and Mac, and how to change the sheet style it defaults to on iPhone.

Discover the power of precise pattern matching with Swift enums as we look into using the where clause in switch statements and for-in loops, and adding extra conditions in while loops and if-case statements for more expressive code.

Ensure that complex SwiftUI buttons have the correct blending in pressed state by applying the compositingGroup() modifier.

Starting from Xcode 14, iOS simulator can generate a device token, allowing us to test remote push notifications coming from a server without a real device or a need to use .apns payload files and simctl push command.

Explore how to replace the position() modifier with a custom AnchoredPosition layout to improve flexibility in aligning views relative to an anchor point, and adjust the alignment dynamically based on available space.

Learn about different use cases for foregroundColor(), foregroundStyle() and tint() modifiers in SwiftUI to be able to choose the right API for the right purpose.

Build an interactive bar chart in Swift Charts that displays detailed annotations when the user is hovering over bar marks.

Enable modified actions, such as command + click or shift + click, in a SwiftUI lifecycle application on iPad using GCKeyboard from the Game Controller framework.

Register when the pointer enters and exists view's bounds and get the mouse cursor location with onContinuousHover() modifier.

Adjust the the default appearance of the ShareLink button using SwiftUI view modifiers such as labelStyle(), imageScale() and symbolVariant().

Find out how text modifiers are different from view modifiers in SwiftUI and how we can use them in our code to style portions of text.

When we add an image name to a Localizable.strings file, SwiftUI automatically uses it for the image accessibility label.

Define custom sizing logic for UIViewRepresentable views in SwiftUI apps with the new iOS 16 sizeThatFits() API.

Create a chart with the Swift Charts framework to show UV index throughout the day inspired by the iOS Weather app that dims the area up to the current time.

Permanently position a view at the bottom of the screen in a SwiftUI app by placing it inside the safeAreaInset() modifier.

Use the accessibilityShowButtonShapes environment value to change the appearance of custom buttons and links embedded in Text views to make them more accessible.

Make sure that all of the necessary strings are localizable in a SwiftUI app by previewing your UI in the accented pseudolanguage.

Add a gradient to a bar chart that stretches from top to bottom of the plot area rather than filling each individual mark.

Generate xcloc files that can be sent to translators directly from SwiftUI code and import translations back to create Localizable.strings files.

Programmatically dismiss presentations and pop views from the navigation stack in both pure SwiftUI and hybrid UIKIt/SwiftUI apps with the help of the dismiss action.

Display a self-updating date and time inside a SwiftUI Text view and prevent the UI from moving as the digits in the date change.

Let users rename items from the navigation title in the toolbar using the new navigationTitle() modifier that takes a binding.

Make all parts of your app readable for users with low vision using the large content viewer APIs.

Set a custom background for TextEditor in SwiftUI by using a combination of scrollContentBackground() and background() view modifiers.

We can use the new Duration type from Foundation to represent an elapsed time value and format it using the new TimeFormatStyle.

We can customize how the user navigates through focusable views in our macOS apps with the help of the new focusSection() modifier.

Build a bar chart using data with values of type Measurement<UnitDuration> that doesn't conform to Plottable by default.

Let users configure the visible items in the center area of the toolbar on iPadOS 16 to suit their personal workflows.

To sort an array based on a particular property in Swift, we can use the KeyPathComparator API from Foundation in combination with sorted(using:) method.

Learn how to use the new openWindow action in SwiftUI to programmatically present new windows in macOS 13.

Make use of the new clock APIs in Swift 5.7 to delay an async task by a certain duration without calling the old method that accepts nanoseconds.

Take advantage of the new URL APIs in iOS 16, which let us obtain paths to system directories more easily without the need to use FileManager methods.

Learn how to change the default position of y-axis in Swift Charts by using chartYAxis() modifier.

Read and set the color scheme in SwiftUI by accessing the environment value, applying preferences for presentations, and customizing specific views or toolbars.

Visualise data distributions by building a histogram and a 2D density plot with the new Swift Charts framework.

The default alignment of SwiftUI List row separators has changed in iOS 16. We also have some new APIs to customize separator insets.

Starting from iOS 16 and macOS 13 we have a SwiftUI API to request App Store reviews. We can read requestReview property from the environment and call it as a function at the appropriate time.

In Swift 5.7 that comes with Xcode 14 we can check if two values of type Any are equal, because we can cast values to any Equatable and use any Equatable as a parameter type.

Tap gesture in SwiftUI now provides the tap location and we can request it in local or global coordinate space.

Starting from iOS 16 and macOS 13 SwiftUI List view can automatically generate move and delete operations without the need of onDelete() and onMove() closures.

With enhanced text modifiers in iOS 16 and macOS 13, it's easy to animate changes to text styles such as font size and weight.

Find and replace feature is automatically supported by SwiftUI TextEditor, but we also have some APIs to customize its behavior, such as disable replace or present the find UI programmatically.

Draw a custom SwiftUI view to replace the symbols in a scatter plot in Swift Charts.

New ViewThatFits API introduced at WWDC 2022 lets us create more flexible layouts in constrained space. It can even help us detect if text is truncated and adapt our views accordingly.

Build a custom ridge chart with the new Swift Charts framework to show the distribution of a numeric variable for several groups.

SwiftUI’s resizable sheet APIs let us present half sheets, define custom detents, and control sheet behavior across different device configurations.

Use the new NavigationSplitView API with a column visibility parameter to programmatically control the visibility of the sidebar in multicolumn navigation in SwiftUI.

Explore the capabilities of the new Swift Charts framework introduced at WWDC 2022 while making a stream graph with custom colour gradient and text labels.

Present a half-sheet in SwiftUI by specifying supported detents with the new presentationDetents() modifier in iOS 16.

Set custom background for a navigation bar in iOS 16 using new SwiftUI toolbarBackground() modifier.

Let's try out the new SwiftUI navigation APIs introduced in beta 1 for iOS 16 and macOS 13: NavigationStack, NavigationSplitView and ways to set up programmatic navigation.

Trigger actions with onChange() modifier in SwiftUI that depend on multiple properties changing by combining the logic in a computed property.

Find out about different ways we can provide feedback about new APIs to Apple engineers, ask questions during WWDC and get help from Apple experts and wider developer community.

Explore different ways to iterate over items and indices in a collection and learn why enumerated() is not a good fit for it.

Take a closer look at AttributedString type and different attribute scopes it can contain. Explore how Apple system frameworks interpret available attributes and how to create your own.

Learn how to size and scale symbol images in SwiftUI and why we shouldn't use resizable() modifier with SF Symbols.

Add custom encoding and decoding logic for SwiftUI Color that is not Codable by default to be able to save it to disk or remote database.

Hide and show a view based on a setting or state without shifting the layout by using opacity() modifier in SwiftUI.

Look into how to insert images, formatted data, attributed strings etc. inside SwiftUI Text views by leveraging the power of string interpolation in LocalizedStringKey.

Present multiple sheets at the same time one on top of the other like, for example, in Apple Calendar app when adding a new calendar.

We have several ways to customize the visual style of links placed inside Text views in SwiftUI: tint() modifier, different Text modifiers and attributes in AttributedString.

SwiftUI Text views can automatically parse Markdown strings when created with LocalizedStringKey. Markdown isn't parsed when created with a String variable or with verbatim initializer.

Customize actions for links inside Text views in SwiftUI by using openURL environment value.

Set underline and strikethrough styles in AttributedString and display it with SwiftUI Text view.

Set a keypath to your model properties as FocusState value to avoid declaring custom enums to programmatically set focus and respond to focus changes.

Build sidebar navigation for your macOS app with the help of selection binding in List view and use SceneStroage for state restoration.

Allow users to select the contents of SwiftUI Text view, to be able to copy or share it, by applying textSelection() modifier.

Learn how to rapidly evaluate a polynomial function of variable size on the GPU without needing to write C++ Metal shaders.

Explore how to get around the Swift language limitation of not being able to define static mutable properties in generic types and protocol extensions.

Make use of the focused scene value API to pass data from the focused scene to the commands section of the app.

Build a system for conforming polymorphic types to Codable protocol, that can be reused in multiple situations.

Customize encoding and decoding logic for individual fields of codable types in Swift by defining codable property wrappers.

Avoid the conflict between the drag gesture and editing of text fields inside list rows and make focusing on text fields easier.

Make use of Xcode shortcuts to correct code indentation quickly.

Change the style of navigation view in document based apps, by hiding the default view and adding our own.

Make an editable list of items in SwiftUI that automatically adds an empty text field for users to easily add new entries.

Define your own operator that lets you use String as default value for any Optional type in debug prints.

Add custom information and copyright to your app's About window on macOS when using the SwiftUI app lifecycle.

Integrate with UndoManager in SwiftUI by building a reusable UndoProvider view that can be used with any binding.

Add RawRepresentable conformance to a custom type that represents a setting or a view state in SwiftUI to be able to save it in AppStorage or SceneStorage.

Remove the default TextEditor background on iOS and add a placeholder that is not currently supported in TextEditor out of the box.

Let users preview various file formats such as Images, Live Photos, PDFs etc. in your SwiftUI app using QuickLook framework.

Provide state restoration for expanded rows in a SwiftUI List view with SceneStorage property wrapper.

Explore how to add support for local network privacy if, for example, your app uses URLSession to access local servers.

Programmatically scroll SwiftUI ScrollView to a newly added item by combining ScrollViewReader and onChange() view modifier.

Implement state restoration in an example tab-based app that stores records of different types of trips.

Build an example social network with Django Channels Rest Framework that lets you subscribe to a hashtag in realtime.

In this article we will look into how to create a custom hover effect in SwiftUI and how to abstract this logic into a reusable view modifier.

View and manage files created by your app on the simulator, browse the Documents folder or Core Data SQLite Database.

Programmatically scroll SwiftUI List to a particular item, using the fact that its internal implementation is based on UITableView.

Publish database changes to subscribed WebSocket clients using Django Channels Rest Framework.

Explore the features of Django Channels REST Framework for building WebSocket API consumers with Django.

Add keyboard shortcuts to a SwiftUI iOS/iPadOS app to improve user experience when using your app with an attached hardware keyboard.

If you need to release an app built with an older version of Xcode, but want to test the app on the beta iOS simulators, you can follow the steps described in this article to transfer your build to the beta simulator.

Build a WebSocket server in Node.js using the ws library and test it with a WebSocket client app.

Make a scrollable view in SwiftUI scroll the active text field into visible range when the keyboard appears on screen in iOS 13.

Buttons inside a List row can cause the entire row to become tappable and trigger multiple buttons at once, but applying a specific button style ensures each button works independently.