Khoa Pham
Khoa Pham

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My year in review 2020

Issue #715

I remember this time last year in December 2019, I spent almost every single bit of my free time on Puma because I want a Swift friendly version of fastlane that suits my need and leverages Swift 5 features.

Here’s my review of my …

How to use Tailwind

Issue #909

Resources

Paid

How to handle status bar with custom overlay UIWindow

Issue #908

When we add another UIWindow, then its rootViewController will decide the style of the status bar, not the rootViewController of the keyWindow anymore

childForStatusBarStyle

The usual way to fix this is to defer the decision to the correct …

How to use SwiftUI Charts

Issue #907

Read more

How to make SwiftUI widget in iOS

Issue #906

Read more

How to use actor in Swift concurrency

Issue #905

Protect mutable state with Swift actors

Actor reentrancy

abc

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 …

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 …

How to show animated gif NSImage on Mac

Issue #903

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

How to handle shortcut intents in iOS

Issue #902

iOS 13 Intents Extension & Intents UI Extension

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 …

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": { …

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 …

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: { …

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 …

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 { …

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 …

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. …

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 { …

Essential WWDC sample codes

Issue #892

WWDC21

My favorite WWDC videos

Issue #891

Below are my favorite WWDC videos. My focus is to use SwiftUI to make useful apps with great UX. I don’t pay much attention to new frameworks as they come and go, but the underlying reasons and design principles are worth …

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 …

WWDC22 SwiftUI Q&A

Issue #890

Interesting SwiftUI Q&A during 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 …

Khoa Pham

Hello, I’m Khoa

I’m a thinker and storyteller with a passion for exploring the intersection of creativity and technology

🧑‍💻 I love crafting high quality and useful apps
🔥 I love open source. My GitHub open source has 2.3k 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 2.7k+ followers with tons of articles and 90k+ monthly views.
🖥 Follow me for sharings about Swift, SwiftUI, iOS and macOS development.
Hei