javascript

Scala.js tutorial: How to start building single-page web applications

Table of Contents1 - Single-page applications2 - 1. Getting started (dependencies)3 - 2. Create hello3.html4 - 3. Create Hello3.scala5 - 4. Run the code!6 - Summary/Discussion7 - Resources8 - More facades9 - Other tutorials in this series10 - Bonus!11 - Source code

In this final, third part of my three-part introductory series on Scala.js I’ll demonstrate a technique that can help you build single-page web applications with Scala.js. That is, the body of your HTML page will look like this:

<body>
    <div id="root"></div>          

    <script type="text/javascript" src="./target/scala-2.12/scala-js-hello-world-jsdeps.js"></script>
    <script type="text/javascript" src="./target/scala-2.12/scala-js-hello-world-fastopt.js"></script>
</body>

After that, your entire application will then be written in Scala/Scala.js, which is converted into JavaScript code in the scala-js-hello-world-fastopt.js file.

A Scala.js tutorial: “Hello, world” with an HTML button click

Table of Contents1 - 1. Create a new HTML page2 - 2. Make updates to use jQuery3 - 3. The new Scala code4 - 4. Setting the main class5 - 5. Running this example6 - Discussion7 - Summary

In my first “Hello, world” Scala.js tutorial I showed how to get started with Scala.js, including some necessary setup/configuration work. That tutorial ended by showing how to get the string “Hello, world” displayed in a browser.

In this tutorial I’ll take this a little further and show how to create an HTML button you can click that results in the string “Hello, world” being displayed in a JavaScript alert window. When the button is clicked, the alert window will be displayed by your Scala/Scala.js code.

Getting started with Scala.js (a “Hello, world” example)

This is the first tutorial in a three-part series on getting started with Scala.js. This tutorial will demonstrate the proverbial “Hello, world” introduction. After this “Hello, world” tutorial, the next two tutorials will show some more powerful things you can do with Scala.js.

How to use `curl` scripts to test RESTful web services

There may be better ways to do this, but when I was writing a mobile app, with the JavaScript client written in Sencha Touch and the server written with the Play Framework, I wrote some curl scripts to simulate GET, POST, DELETE, and PUT request (method) calls to my Play Framework REST/RESTful web services.

The lack of type safety was difficult to scale ...

From this AirBnB article about using React Native: “JavaScript is an untyped language. The lack of type safety was both difficult to scale and became a point of contention for mobile engineers used to typed languages who may have otherwise been interested in learning React Native ... A side-effect of JavaScript being untyped is that refactoring was extremely difficult and error-prone.”

Using structs in JavaScript (example, syntax) alvin May 15, 2018 - 4:28pm

Bearing in mind that I rarely use JavaScript and I’m not an expert in it, I like the idea of using something like a C-like “struct” in my JavaScript code, so I used the following approach on a recent project. First, I define my JavaScript struct:

function Book(title, href, imageUri, description) {
    this.title = title;
    this.href = href;
    this.imageUri = imageUri;
    this.description = description;
}

Then I define an array of Book types:

How to get multiple, random, unique elements from a JavaScript array alvin April 18, 2018 - 3:39pm

As a note to self, this JavaScript code gets multiple, random, unique elements from a JavaScript array and displays three of those elements in the second div: