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 sign in with Apple and Firebase and Supabase

Issue #977

Show ASAuthorizationController with a simple nonce. Once we have the idToken, create an OAuthProvider.appleCredential and pass to Firebase Auth

final class AppleLoginService: NSObject {
    static let shared = AppleLoginService() …

How to serve a local development environment over https using pnpm and webpack

Issue #976

When developing locally, especially when interacting with third-party services that have CORS restrictions, serving your development environment over a custom domain with HTTPS can be crucial. Let’s walk through the steps to achieve this …

How to use React Custom Hooks as the View Model pattern

Issue #975

When building a React application, separating the logic and state management from the UI can make your code easier to manage, test, and reuse. This is where the view model pattern comes in handy. By using a custom hook as a view model, you …

How to use memory in lowdb

Issue #974

In lowdb 7, we can use MemorySync https://github.com/typicode/lowdb/blob/main/src/examples/in-memory.ts

import { LowSync, MemorySync, SyncAdapter } from '../index.js'
import { JSONFileSync } from '../node.js'

declare …

How to detect Barcode and QR code

Issue #973

Before iOS 11, we used to use CIDetector and CIDetectorTypeQRCode to detect QR code

CIDetector

An image processor that identifies notable features, such as faces and barcodes, in a still image or video.

CIDetectorTypeQRCode

A detector …

How to make swifty UserDefaults

Issue #972

We want to have a swifty UserDefaults API that works with subscript and in a type safe manner.

extension Defaults.Keys {
    static let string = Defaults.Key("string", default: "0")
}

XCTAssertEqual(defaults[.string], …

How to use act vs waitFor using React Testing Library

Issue #971

When testing React components, dealing with tasks that happen at different times is super important to make sure your tests give reliable results. React Testing Library gives you two important tools for dealing with these situations: act …

How to use OSLog and OSLogStore in Swift

Issue #970

We can use Logger to log and OSLogStore to retrieve logs

import OSLog
import ReuseAcross

final class LogService {
    static let shared = LogService()
    
    let logger = Logger(
        subsystem: "com.example.myapp", …

How to include custom error payload in hapi Boom

Issue #969

Hapi.js, commonly referred to as Hapi, is an open-source, back-end web application framework for building and deploying web applications and APIs in Node.js

In Hapi.js, you can use the Boom module to create and return error responses in a …

How to read image paste from clipboard in React

Issue #968

Are you looking to grab images directly from your clipboard with a button click on your web page? The Async Clipboard API makes this quite easy and efficient. Let’s break it down into simpler steps:

Requesting Permission

The first …

How to create user gitignore

Issue #967

Git is a helpful tool for managing code and projects, but sometimes you want to ignore certain files or folders only on your computer without affecting everyone else. That’s where the .user_gitignore file comes in. It allows you to …

How to use useCallback in React

Issue #966

The use of useCallback and useMemo in React hooks is an adaptation to address certain limitations inherent in the functional programming style adopted by React. In JavaScript, every entity, whether it’s a function, variable, or any …

How to extend class in Javascript

Issue #965

In JavaScript, classes are a template for creating objects. They encapsulate data with code to work on that data. ES6 introduced a class syntax to the JavaScript language to create classes in a way that’s similar to other …

How to use export all and export default in Javascript

Issue #964

In JavaScript, particularly in modules used in frameworks like React, export statements are used to expose code—such as functions, classes, or constants—from one module so that they can be imported and reused in other modules.

export *

The …

How to escape characters in json and regex with Swift string

Issue #963

In the world of Swift programming, we often come across situations where we need to work with string literals that contain special characters. These characters can include new lines, tabs, backslashes, and quotes — all of which need to be …

How to use nextjs Image

Issue #962

Fill parent div

A boolean that causes the image to fill the parent element, which is useful when the width and height are unknown.

The parent element must assign position: “relative”, position: “fixed”, or position: …

How to check NSTextField is first responder

Issue #961

NSTextField uses NSFieldEditor under the hood, you can check currentEditor if it is the firstResponder

extension NSTextField {
    var isFirstResponder: Bool {
        currentEditor() == window?.firstResponder
    }
}

Building an iOS camera calculator with Core ML’s Vision and Tesseract OCR

Issue #960

Also written on Fritz


Math might be scary, but it’s an essential part of everyday life. Wouldn’t it be cool if we could build an app, point our phone’s camera at an expression, and let the app compute the result? Whenever I’ve needed to …

How to decode dynamic JSON key with JSONDecoder

Issue #959

Decoding JSON in Swift is most of the time very straightforward with help of Codable protocol and JSONDecoder.

Sometimes the json contains dynamic key, like

{
    "shipmunk": {
        "name": "Shipmunk", …

How to bundle js for use in JavaScriptCore in Swift

Issue #958

We can use any bundler, like Parcel, Webpack or Vite. Here I use Webpack 5

Install Webpack and Babel

npm install @babel/polyfill webpack webpack-cli --save-dev

@babel/polyfill is a package provided by Babel, a popular JavaScript compiler. …

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