Browser-less Unit Testing your React/Redux Code with Mocha, Chai, and Enzyme

A lot of JavaScript applications out there require having a browser available to run your unit tests.  For years it seemed like the de-facto configuration for unit testing was some combination of Karma, PhantomJS, and either QUnit or Jasmine.  While I think that there is definitely value in making sure that your application runs properly in a browser, given that that is how your users will interact with it, my personal opinion is that the majority of your test suite should be able to be run outside of a browser environment.  This article will describe what Enzyme brings to the table in terms of unit testing your React/Redux code without needing a browser.

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Using Aurelia’s Dependency Injection Library In Non-Aurelia App, Part 2

In my last post, we looked at Aurelia’s dependency injection library and how you might be able to use it as a standalone library in your vanilla JavaScript application.  Now, however, I want to take a look at how you might be able to wire it into your React application, and then finally how you might hook it into React/Redux application.

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Using Aurelia’s Dependency Injection Library In Non-Aurelia App, Part 1

If you are anything like me then you like to try to keep your code loosely coupled, even your JavaScript code.  The ES2015 module spec helped solve a lot of issues with dependency management in JavaScript apps, but it did not really do anything to prevent having code that is tightly coupled to the specific imports. When Aurelia was originally announced, one of the things that first caught my eye was that it included a dependency injection library that was designed to be standalone so you could use it even if you were not including the rest of the Aurelia framework.  Now that Aurelia has had some time to mature, I decided to see how exactly it might look to use the dependency injection library in a variety of non-Aurelia applications.

In this two-part blog series, I will unpack a few basics about the library itself, and then show how it might be used in three different apps: a vanilla JavaScript app, a React app, and then a React app that uses Redux for its state management.

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Coping with Device Rotation in Xamarin.Android

You think that you have your Android application in a state where you can demo it to your supervisor when you accidentally rotate your device and the app crashes. We have all been there before and the good news is that the fix is usually pretty simple even if it can sometimes take awhile to find.

This has always been an issue for Android developers, but I have found that, due to the unique interaction between your C# classes and the corresponding Java objects, it seems to be a little more sensitive with Xamarin.Android apps. In this post, we will discuss what happens when you rotate your device and cover the different techniques that you might choose to use to manage your application state through device rotations as well as the ramifications of each of them.

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A Dive into SystemJS – Production Considerations

Previously we have looked at the basic configuration of SystemJS and what happens when you attempt to load modules. What we have covered so far is good enough for a development system, but things are different when you try to push your code to production and performance is much more important. It might be fine for a development system to make XHR requests for each individual script file, but that is not ideal for most production systems. This article will attempt to evaluate the production setup that is needed to attain good performance. [Read more…]

A Dive into SystemJS – Loading and Translating

In the last article we took a look at some of the basic configuration options of SystemJS and also the high level workflow of what happens when you attempt to import a module. This article is going to walk through what happens from when a script has been fetched by the browser until a module instance is returned, as well as provide some information on creating plugins for SystemJS. [Read more…]

A Dive into SystemJS – Part 1

The ECMA2015 module syntax for JavaScript was a much needed addition to the language. For years now the JavaScript community has tried to make up for the lack of a standard module format with several competing formats: AMD, CommonJS, and then UMD which tried to wrap both of the others. The introduction of an official module syntax, details of which can be found at the MDN imports documentation page, means that there is going to be a new module loader required to load the new format. Unfortunately the ECMA2015 specification ended up not including a module loader, but there is a proposal with the WhatWG team to add a module loader to the browser. SystemJS is a module loader built on top of the original ES6 module loader polyfill and soon to be the polyfill for the WhatWG module loader. This series of articles is going to take a deep dive into SystemJS and see what all it has to offer. [Read more…]

Working with the HTML Selection API

The HTML Selection API gives developers the ability to access highlighted text within the browser and perform some DOM and text manipulation on the selected text. These useful features are available now in any modern browser as well as legacy browsers back to IE9. While there are more complex things that can be done with this API this blog article will hopefully illustrate some possible uses of the API and give you an idea of how to start using some of these features.
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Sencha Touch

Mobile applications are everywhere these days and the number of development frameworks geared towards mobile audiences is growing as well. This can make it difficult for us developers who have to spend valuable training time learning one or more of these frameworks in order to be able to do our jobs. Sencha Touch is one of these frameworks and it allows a developer to code in HTML, CSS, and Javascript, and then package up the application to run on different mobile devices. This article is intended to provide a general feel for what Sencha Touch is and what it does.
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Garbage Collection and the Finalizer

One aspect of modern web development that sometimes seems to be taken for granted is memory management. While you might not need to create a custom boot disk anymore in order to run your application on a modern machine, it is still important to understand how your memory allocations are cleaned up. Two of the main components to cleaning up memory allocation are the garbage collector and the finalizer.
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