Hi there, I’m Khoa aka onmyway133 👋

  • 🧑‍💻 I love crafting high quality and useful apps

  • 🔥 I love open source. My GitHub open source has 1.6k followers with packages that are integrated by 45k+ apps and over 3.4m+ downloads on CocoaPods.

  • ✍️ I write here on my blog and on Medium, which has over 2.4k+ followers with tons of articles and 90k+ monthly views.

  • 🖥 Follow me for sharings about Swift, SwiftUI, iOS and macOS development

How to use SwiftUI Charts

Issue #907 Read more https://swdevnotes.com/swift/2022/customise-a-line-chart-with-swiftui-charts-in-ios-16/ https://github.com/jordibruin/Swift-Charts-Examples

October 30, 2022 · 1 min · Khoa Pham

How to make SwiftUI widget in iOS

Issue #906 Read more https://developer.apple.com/documentation/widgetkit/making-a-configurable-widget What is the purpose of getSnapshot method from WidgetKit

October 30, 2022 · 1 min · Khoa Pham

How to use actor in Swift concurrency

Issue #905 Protect mutable state with Swift actors Actor reentrancy Imagine we have two different concurrent tasks trying to fetch the same image at the same time. The first sees that there is no cache entry, proceeds to start downloading the image from the server, and then gets suspended because the download will take a while. While the first task is downloading the image, a new image might be deployed to the server under the same URL....

October 5, 2022 · 4 min · Khoa Pham

How Task use thread in Swift concurrency

Issue #904 Consider this code where we have an ObservableObject with fetch1 and async fetch2, and a fetch inside ContentView Here the observation in Xcode 14 ViewModel.fetch1: run on main thread ViewModel.fetch2: run on cooperative thread pool ContentView.fetch: run on main thread import SwiftUI import CoreData import Combine class ViewModel: ObservableObject { @Published var string = "" func fetch1() { let url = URL(string: "https://google.com")! let data = try!...

October 4, 2022 · 4 min · Khoa Pham

How to show animated gif NSImage on Mac

Issue #903 let image = NSImage(contentsOf: url) let imageView = NSImageView(image: image) image.animates = true

September 25, 2022 · 1 min · Khoa Pham

How to handle shortcut intents in iOS

Issue #902 iOS 13 Intents Extension & Intents UI Extension Donate Shortcuts at the Right Time Siri can predict shortcuts to actions that a user may want to perform using your app, and suggest those shortcuts to the user in places such as Spotlight search, Lock Screen, and the Siri watch face. Siri learns about the shortcuts available for your app through donations that your app makes to Siri....

September 14, 2022 · 3 min · Khoa Pham

How to use Universal Links in iOS

Issue #901 Apple app site association https://com.example/.well-known/apple-app-site-association Supporting Associated Domains New format from iOS 13 Can also remove components section if we match all URLs { "applinks": { "details": [ { "appIDs": [ "ABCDE12345.com.example.app", "ABCDE12345.com.example.app2" ], "components": [ { "/": "/*", "comment": "Match all URLs" } } ] }, } Application Identifier Prefix appID is in form <Application Identifier Prefix>.<Bundle Identifier> For Application Identifier Prefix , you can find it in https://developer....

August 9, 2022 · 3 min · Khoa Pham

How to find previous frontmost application in macOS

Issue #900 Listen to didActivateApplicationNotification and check that it is not our app NSWorkspace.shared.notificationCenter .publisher(for: NSWorkspace.didActivateApplicationNotification) .sink(receiveValue: { [weak self] note in guard let app = note.userInfo?[NSWorkspace.applicationUserInfoKey] as? NSRunningApplication, app.bundleIdentifier != Bundle.main.bundleIdentifier else { return } self?.frontMostApp = app }) .store(in: &bag)

August 2, 2022 · 1 min · Khoa Pham

How to show view below title bar for macOS in SwiftUi

Issue #899 Use NSTitlebarAccessoryViewController var titleBarAccessoryVC: NSTitlebarAccessoryViewController { let vc = NSTitlebarAccessoryViewController() let view = HStack { Spacer() Button { } label: { Text("Save") } .buttonStyle(.borderedProminent) .controlSize(.large) } .padding(.horizontal) vc.view = NSHostingView(rootView: view) return vc } let window: NSWindow = ... window.addTitlebarAccessoryViewController(titleBarAccessoryVC)

July 30, 2022 · 1 min · Khoa Pham

How to drag using DragGesture in SwiftUI

Issue #898 Change element position using either offset or position, and use DragGesture Use GestureState to store the updating startDragLocation to keep the start location when drag begins, so we can add translation struct MoveModifier: ViewModifier { @Binding var position: CGPoint @GestureState private var startLocation: CGPoint? func body(content: Content) -> some View { content .gesture(gesture) } private var gesture: some Gesture { DragGesture() .onChanged { value in var position = startLocation ?...

July 28, 2022 · 1 min · Khoa Pham

How to handle slow large dataset Picker when dragging in SwiftUI

Issue #897 During continuous events like dragging or TextField typing, and we have a Picker onscreen with large data set, it will slow down main thread. One option is to explicitly conform that view to Equatable struct FontPicker: View, Equatable { @Binding var fontFamily: String var body: some View { Picker("", selection: $fontFamily) { ForEach(NSFontManager.shared.availableFontFamilies, id: \.self) { family in Text(family) .tag(family) } } } static func == (l: FontPicker, r: FontPicker) -> Bool { l....

July 28, 2022 · 1 min · Khoa Pham

How to pass FocusState binding in SwiftUI

Issue #896 Use underscore _focus we get access to underlying FocusState object, but underscore _ is private to a View hence can’t be used in extension If we want to pass FocusState to another View or in extension, we can pass its Binding enum FocusElement: Hashable { case name case email } struct ParentView: View { @FocusState var focus: FocusElement? var body: some View { ChildView1(focus: _focus) ChildView2(focus: $focus) } } struct ChildView1: View { @FocusState var focus: FocusElement?...

July 28, 2022 · 1 min · Khoa Pham

How to move reversed List in SwiftUI

Issue #895 Apply .move on reversed array List(selection: $viewModel.selectedBook) { ForEach(viewModel.books.reversed()) { book in BookCell(book: book) } .onMove { source, dest in var reversed = Array(viewModel.books.reversed()) reversed.move(fromOffsets: source, toOffset: dest) viewModel.books = reversed.reversed() } }

July 25, 2022 · 1 min · Khoa Pham

How to set popoverPresentationController sourceView in SwiftUI

Issue #894 Use a UIView as source view and set it in background class ViewModel { lazy var sourceView = UIView() } struct SourceView: UIViewRepresentable { let viewModel: ViewModel func makeUIView(context: Context) -> UIView { viewModel.sourceView } func updateUIView(_ uiView: UIView, context: Context) {} } Button(action: { onShowAlert(viewModel.sourceView) }) { Image(systemName: "bookmark") } .background(SourceView(viewModel: viewModel)) let alertController = UIAlertController(title: nil, message: nil, preferredStyle: .actionSheet) alertController.popoverPresentationController?.sourceView = viewModel.sourceView

July 8, 2022 · 1 min · Khoa Pham

Essential WWDC sample codes

Issue #892 WWDC21 Building a Great Mac App with SwiftUI Add Rich Graphics to Your SwiftUI App

June 10, 2022 · 1 min · Khoa Pham

My favorite WWDC videos

Issue #891 WWDC18 Designing Fluid Interfaces Testing Tips & Tricks WWDC22 The craft of SwiftUI API design: Progressive disclosure Writing for interfaces Read more https://onmyway133.com/posts/favorite-wwdc-2017-sessions/ https://onmyway133.com/posts/favorite-wwdc-2018-sessions/ https://onmyway133.com/posts/favorite-wwdc-2019-sessions/ https://www.hackingwithswift.com/articles/239/wwdc21-wrap-up-and-recommended-talks https://www.hackingwithswift.com/articles/190/the-best-wwdc-videos-of-all-time

June 10, 2022 · 1 min · Khoa Pham

WWDC swiftui-lounge

Issue #890 In WWDC21, WWDC22 Apple provide a Slack channel https://wwdc22.slack.com/ for people to interact with Apple engineers in digital lounges. Here I note down some interesting Q&As WWDC22 What’s the difference between a custom ViewModifier vs View extension Q: What’s the difference between a custom ViewModifier (without DynamicProperty) that uses some built-in modifiers in body(content:), and a custom View extension func that just use those built-in modifiers? Similarly, what’s the difference between a custom ViewModifier with some DynamicProperty and a custom View with some DynamicProperty (also has a @ViewBuilder content property to receive content to modify) ?...

June 10, 2022 · 32 min · Khoa Pham

What's new in SwiftUI iOS 16 at WWDC22

Issue #889 What’s new in SwiftUI New EnvironmentValues TextField inside Alert List uses UICollectionView See gist https://gist.github.com/onmyway133/fc08111964984ef544a176a6e9806c18 ButtonStyle composition Section("Hashtags") { VStack(alignment: .leading) { HStack { Toggle("#Swiftastic", isOn: $swiftastic) Toggle("#WWParty", isOn: $wwdcParty) } HStack { Toggle("#OffTheCharts", isOn: $offTheCharts) Toggle("#OneMoreThing", isOn: $oneMoreThing) } } .toggleStyle(.button) .buttonStyle(.bordered) } Customize Charts struct MonthlySalesChart: View { var body: some View { Chart(data, id: \.month) { BarMark( x: .value("Month", $0.month, unit: .month), y: .value("Sales", $0.sales) ) } ....

June 9, 2022 · 5 min · Khoa Pham

How to use any vs some in Swift

Issue #888 Embrace Swift generics This generic pattern is really common, so there’s a simpler way to express it. Instead of writing a type parameter explicitly, we can express this abstract type in terms of the protocol conformance by writing “some Animal”. The “some” in “some Animal” indicates that there is a specific type that you’re working with. func feed<A>(animal: A) where A: Animal {} func feed(animal: some Animal) An abstract type that represents a placeholder for a specific concrete type is called an opaque type....

June 8, 2022 · 5 min · Khoa Pham

How to use Swift

Issue #887 What’s new https://www.whatsnewinswift.com https://www.hackingwithswift.com/articles/249/whats-new-in-swift-5-7 https://www.hackingwithswift.com/articles/247/whats-new-in-swift-5-6

June 7, 2022 · 1 min · Khoa Pham