Kotlin |

Awaiting Kotlin suspend functions in serial, parallel and lazy startup modes

May 12, 2023 · 4 min read · Kotlin ·

Kotlin allows a thread of execution to be suspended until some other asynchronous function completes and returns a result. Suspend functions are most commonly used when a response from an external resource is needed to complete the suspend function. Most often the external resource is a web service API or a connected …

Filtering Collections in Swift, Kotlin and JavaScript

May 12, 2023 · 2 min read · Swift Kotlin JavaScript ·

Share on:

Extracting members of a collection that match some filtering predicate is a common pattern in programming. Traditionally we would iterate over all members (e.g. with a for or foreach loop), and save each member matching some condition. Most programming languages now provide some single step filter function to eliminate …

REPL Tool Reference

May 11, 2023 · 1 min read · Swift Kotlin JavaScript ·

Share on:

It's helpful to experiment with language syntax in a REPL tool before pasting code into your editor. REPL is an acryonym for Read, Evaluate, Print, Loop. REPL tools are simple interactive programming environments primarily used to validate syntax and algorithms. Swift The main Swift REPL tool is the Playground feature …

Android Jetpack Compose View Model Eventing Architecture

Apr 14, 2023 · 5 min read · Kotlin Jetpack Compose ·

Share on:

A common Android architectural pattern is to consume events in a UI View that are triggered from asynchronous web service code in a View Model. While there are many approaches to solving this problem, I wanted to share the approach I often use. You may have another approach that works even better, but this approach has …

Using Firebase Auth claims with Swift, Kotlin and JavaScript

Apr 13, 2023 · 4 min read · Backend JavaScript Swift Kotlin ·

Share on:

Firebase Authentication supports built-in and custom user claims that allow us to conditionally expose functionality to users based on authorization groups. This post demonstrates the syntax to add custom claims in a Firebase backend, and read claims from mobile apps. What are Claims? In identity systems, a …

Simple For Loop in Swift, Kotlin and JavaScript

Apr 8, 2023 · 3 min read · Swift Kotlin JavaScript ·

Share on:

A core feature of all programming languages is the trusty for loop. For loops execute a statement a predefined number of times with some way to exit the loop early. Swift Swift uses range operators to construct simple for loops. 1let start = 0 2let end = 10 3 4for i in start ... end { 5 print(i) // prints 0 through 10 …

Async/Await Syntax in Swift, Kotlin and JavaScript

Apr 6, 2023 · 3 min read · Swift Kotlin JavaScript ·

Share on:

Most modern languages support the ability for asynchronous function calls to be called from synchronous code blocks. This language feature is usually called async/await. This post is a brief syntax scratchpad comparing async/await in different languages. Swift In Swift, an await-able async function is created by adding …

ForEach Syntax in Swift, Kotlin and JavaScript

Apr 3, 2023 · 3 min read · Swift Kotlin JavaScript ·

Share on:

ForEach is a common pattern in programming modern programming languages. Prior to ForEach, the standard approach to iterating over an array of objects was to use a for loop stepping from the first index to the last. ForEach syntax has extra utility in languages that support many types of collections: a list iterated …

Checking for Google Play Services with Kotlin

Aug 5, 2022 · 2 min read · Kotlin ·

Share on:

In many countries we can assume Android users use devices that have Google Play Services pre-installed, but not every Android device in the world actually does. It's possible that code written with the assumption that Play Services is available may crash--something we certainly don't want. What we do want is to have …

Adding a dropdown menu to a Jetpack Compose TopAppBar

Sep 19, 2021 · 4 min read · Jetpack Compose Kotlin ·

Share on:

Adding a dropdown menu to a Jetpack ComposeTopAppBar is quite easy, but simple examples aren't so easy to find! This post has a canonical example to use as a basis for your dropdown menu. Add a Scaffold that Includes a TopAppBar The first step is to create the Compose view as a Scaffold that assigns a new TopAppBar to …