This post is part 77 of 92 in the series Programming by Stealth

My plans for this instalment were to quickly demonstrate so-called callback hell, and then move on to the solution, JavaScript Promises, but in light of some listener feedback I changed my plans a little. There was some confusion in the community about what callbacks really are, so, now seemed like an opportune moment to spend a little time re-familiarising ourselves with some callback basics. This sets things up for a bit of a teaser-ending because we’ll get as far as demonstrating callback hell, but not as far as using Promises to get back out of hell, that will have to wait until the following instalment!

You can download this instalment’s ZIP file here.

Read more

Tagged with:

This post is part 76 of 92 in the series Programming by Stealth

Having laid a very strong foundation in the previous instalment, we’re now ready to learn how to make HTTP requests with JavaScript using a technique known as AJAX.

We’ll start our journey into AJAX using more traditional JavaScript techniques, i.e. we’ll use callbacks to handle HTTP responses. As we’ll discover, this works very well for single AJAX requests, but the model really starts to get complicated when you have multiple inter-dependent requests. We won’t complicate things in this instalment though — we’ll start with just simple stand-alone requests this time.

You can download this instalment’s ZIP file here.

Read more

Tagged with:

This post is part 75 of 92 in the series Programming by Stealth

Having wrapped up our introduction to Mustache templates we’re going to spend the next few instalments learning about AJAX, a very powerful JavaScript technique for loading information from a given URL. In future instalments we’ll use this technique to load external templates and data for use with our Mustache templates.

AJAX is a mechanism for making a HTTP requests via JavaScript, so before we’re ready to learn about AJAX we need to take the time to learn about the HTTP protocol itself. Unless you understand the mechanics and the terminology of HTTP, AJAX-related documentation simply won’t make any sense.

Read more

Tagged with:

This post is part 74 of 92 in the series Programming by Stealth

In the previous instalment we got our first look at Mustache templates. In this instalment we’ll finish our look at this handy little third party library with a look at some of Mustache’s more advanced features. This will set us up perfectly to finally introduce AJAX into this series. This is an extremely common technique for fetching external resources with JavaScript. We’ll learn how to use AJAX to fetch both Mustache template strings and JSON data from URLs.

You can download this instalment’s ZIP file here.

Read more

Tagged with:

This post is part 73 of 92 in the series Programming by Stealth

In the previous instalment we took our first look at using templates with JavaScript to create cookie-cutter content like Toast notifications more easily than building them up piece-by-piece with jQuery. We started our exploration of the topic with a look at HTML5’s new <template> tag. In this instalment we’ll introduce a third-party templating tool, Mustache, and see how it can take our templates to the next level with concepts like conditional and looped sections.

You can download this instalment’s ZIP file here.

Read more

Tagged with:

This post is part 72 of 92 in the series Programming by Stealth

Templating is a very important concept to get to grips with as you move from web pages to web apps. You need the ability to design some generic HTML and then easily inject data into it. Every UI popup has a standard form, but the information being displayed changes each time its invoked. Similarly, apps often use some kind of card interface to show a collection of similar items, those are basically the same piece of HTML being re-used with different data over and over again. Clearly, you want to be able to easily create a template for one card, and then re-use it over and over again.

I’ve been trying to find the perfect moment to insert this topic into the series, and it struck me that Bootstrap Toasts would make a simple but informative example around which to introduce the topic. So far we’ve been generating toasts by building them up piece-by-piece with jQuery, starting with a tag, setting the text, setting some attributes and properties, adding some classes, appending tags together, and so on. The code works, but it’s cumbersome to write, and worse still, difficult to debug and maintain. Hopefully you’ve been thinking to yourself ‘there must be a better way?’, because if you have been, you’ll be very well motivated to ingest this instalment!

You can download this instalment’s ZIP file here.

Read more

Tagged with:

This post is part 71 of 92 in the series Programming by Stealth

The challenge set at the end of the previous instalment was to build a simple timer web app. This was a much more substantial challenge than those I’ve been setting in the previous handful of instalments, and in involved re-familiarising yourself with concepts we’ve learned before, but not used for some time. For those reasons this instalment will primarily revolve around my sample solution to the challenge. I’ll go through it in much greater detail than I have been doing recently.

It would be a shame to go through an entire instalment without any new content though, so we also meet one very simple but very useful little Bootstrap component, the Spinner. Learning about the spinner sets us up nicely for a new challenge — two simple but important improvement to the timer web app we just built.

You can download this instalment’s ZIP file here.

Read more

Tagged with:

This post is part 70 of 92 in the series Programming by Stealth

In this instalment we’ll continue our recent focus on Bootstrap components primarily intended for use in web apps rather than on web pages. We’ll look at a pair of components designed to notify of something — modal dialogue boxes, and so-called toast notifications.

Different notifications require a different UI, hence there being two components, Modal, and Toast. However, both are quite similar in the sense that you will most probably be triggering them via JavaScript. Unlike the other components we’ve seen so far, these will not be visible to the user when the page loads, they’ll make their presence felt at some later time in response to some kind of event.

You can download this instalment’s ZIP file here.

Read more

Tagged with:

This post is part 69 of 92 in the series Programming by Stealth

In the previous instalment we learned how to use Navs for creating navigation bars, and learned how to use Dropdowns to add expandable menus to our Navs. In this instalment we’ll meet Bootstrap’s ultimate navigation component, the Navbar. This is a powerful component designed to act as the menubar at the top of websites or web apps.

You can download this instalment’s ZIP file here..

Read more

Tagged with:

This post is part 68 of 92 in the series Programming by Stealth

In this instalment we’ll get our first look at Bootstrap’s so-call Nav component, a menu designed to facilitate navigation around a website, within a page, or within a web app. In the previous instalment we met Dropdowns for the first time, and saw how Dropdowns filled with buttons can be used within web app UIs. We ended by noting that Dropdowns come in two flavours, buttons and links. In this instalment we’ll learn how to use the link-flavour of Dropdowns within Navs. Finally, we’ll learn how to use Navs to create tabbed content regions within a web page or web app.

You can download this instalment’s ZIP file here.

Read more

Tagged with:

« go backkeep looking »