Rob Gravelle

Script Debugging Using the Internet Explorer Developer Tools If you’ve done much JavaScript development, you’re probably quite familiar with Firefox’s excellent Firebug tool for debugging your scripts. Microsoft’s Internet Explorer browser has a similar feature called Internet Explorer Developer Tools. It’s purpose it to help debug JScript code, the version of ECMAScript that runs on […]

Create a Win/Loss Chart with PlotKit I recently wrote an article entitled Customizing PlotKit Chart Axes in which I briefly addressed how to set up chart axes to accommodate negative dataset values. While PlotKit can certainly work with negative values, I found that bar charts did not manifest themselves as expected. Instead of originating at […]

2/22/13 When I chose to compare some of the more well-known HTML5 libraries, I really didn’t have a firm grasp of what I was in for! There is a seemingly endless supply of worthy charting libraries, both of the open source and commercial varieties. In the hopes of keeping this article from expanding to book […]

2/18/13 The HTML Canvas element has given Web developers the ability to affect images in the browser much like expensive graphics software like Photoshop, all without altering the original file. In the Display Images in Black & White Using the HTML5 Canvas article, we saw how to create a really good grayscale effect using a […]

In the A Quick Tour of Douglas Crockford’s JSLint article, I ran some of my own code through Douglas Crockford’s JSLint, an online code quality tool for JavaScript. The analysis revealed quite a number of deviations from established JavaScript best practices in my code. In that article, I only described a few error messages and […]

In the Testing JavaScript Using the Jasmine Framework article, we learned how to test our JavaScript code using a JavaScript enabled browser and the Jasmine Testing Framework. In this article, we’re going to move on to spying on our methods using mocks. Re-Mock-able One of the primary aims of unit testing is to isolate a […]

In most Android devices, your location-based or map applications can determine the current geolocation using either GPS (Global Positioning System), cell tower triangulation, or wifi networks. With regards to GPS, Eclipse provides a tool to simulate coordinates in a way that mimics real-life usage. It’s called the GPS Emulator Control. The tool features a Dalvik […]

The Variable Naming Conventions in JavaScript article only scratched the surface of Variable Naming conventions in JavaScript. This article introduces more in-depth info on how to make your code both more readable and maintainable. Objects vs. Instances While all variables are written in Camel Case (e.g. CamelCase), object identifiers have the distinction of starting with […]

In the Accessing Private Functions in JavaScript article, we explored a means of gaining access to an object or method’s inner helper functions in order to be able to test them using a framework such as Jasmine. In today’s follow up, we’re going to learn how to fetch nested functions using an iterative solution. Revisiting […]

Following in the footsteps of Three JavaScript Anti-Patterns and How To Avoid Them, this article presents some useful patterns that are specifically aimed at aiding in the creation of Objects. Remember that a programming pattern represents a template for how to solve a problem that can be used in many different situations. The specific patterns […]

As mentioned in my Passing JavaScript Function Parameters By Reference article, objects are passed to functions by reference in JavaScript. In other words, the function receives a pointer that references the original object. The benefit to this approach is that it saves memory and processing resources. Unfortunately, it can lead to trouble if the function […]

11/27/2012 There are two ways that a function argument, or parameter, can be passed to it: by value or by reference. In the first instance, a copy of the variable is made when the function receives it. Hence, any changes made to the passed variable within the function end when the function returns or exits […]