Promises with dojo – a lightweight alternative to dojo.Deferred

Update: Micheil Smith had a cool idea to improve this and posted it in the comments. I have updated the test page and the code examples to reflect his idea. Thanks Micheil!

Update II: Ben Hockey proposed to do the whole thing without using the pub/sub system. I for one think its a good idea, but in case you want the topic version, I’ll leave the test page and add another one with the topic-less version. Thanks Ben!

One of the things/ideas/concepts that I really like about CommonJS is Promises.

Promises? A brief explanation from the CommonJS API:

Promises provide a well-defined interface for interacting with an object that represents the result of an action that is performed asynchronously, and may or may not be finished at any given point in time.

To hear more about Promises, I highly recommend these two posts.
Read more

Working with the Curve – Advanced Animation with Dojo

If you use animations, you probably use them to animate CSS properties. But this post is about some real bareknuckle animation – using the dojo toolkit. We’ll have a look into dojo.Animation and talk about the curve, the line, easing and rate, and we’ll check out (the somehow undocumented) dojox.fx._core – and see how to work with multidimensional lines.

Read more

persistent local storage with dojo

Last year, Brian Leroux’s Lawnchair caught my interest – it is an easy and fast way to access local persistant local storage.

Uh, persistant local storage?

Ahm, yeah, in case you don’t know, that means a client-side storage, be it in a browser, or in an Air app. It’s not very popular, but that concept has been around for a long time. So why local? There are two major reasons for it: First, we need this for apps and tools that work offline – and apps and tools that work online but need an offline backup and sync later. Kris Zyp wrote a post about the JsonRestStore and OfflineRest back in 2008, he goes a little into detail there. Secondly, we need it for apps and tools that rely on persistence for other reasons, no matter if online or offline – like it happended to me. When I ran into Lawnchair, I had the idea to build a tool that was monitoring CSS selector usage on websites and apps (you know how you sometimes lose control about CSS selectors in webapps…). To achieve this, I needed to store data locally, and persistent.
Read more

More fun with strings: dojo.string.contains()

In the series “convenience wrappers for small tasks that increase code readability”, today contains() is starring. Having a contains() method could also serve another purpose: to maybe prevent people from using match() to find out if a string contains a given substring (what is still proposed in some JS tutorials out there…). So, I want the contains() method to also have a switch to work case-insensitive.

Besides indexOf(), there are some other ways to achieve this, so – let’s have a competition and find out who’s the fastest!
Read more

Keyboard accessibility for dojox.layout.FloatingPane

Well, I don’t really see a use for FloatingPane, except as a windowing system for projects like LucidDesktop, but I got the impression that many people just love the FloatingPane. However, it caught my attention these days.

One of its major drawbacks – and the one that keeps it pretty far from becoming a joyful member of the dijit namespace – is the lack of keyboard accessibility. It has plenty of other issues and could use some refactoring, but this one is outstanding. Hm, adding keyboard access shouldn’t be too hard I thought and went for it…
Read more

dojo.string.beginsWith()

Most cases where you find String.substr() in the wild are to check if a given string begins with a certain other string. Be it checking for a prefix or sorting out zipcodes that begin with certain numbers. And because code readability is a good thing (really, it is important), it would be nice to have a String.beginsWith() method. Or, because of dojo love, a dojo.string.beginsWith() method.

Consider the following code:

var nearbyZipcodes = dojo.filter(givenZipcodes,function(zipcode){
    return dojo.string.beginsWith(zipcode,'12');
});

Read more

A collapsible fieldset as dojo widget

Though many people would disagree, I for one like to use fieldsets to structure complex forms. Even better do I like fieldsets that are collapsible.

As there is no such fieldset with dojo, I decided to write my own widget. While doing so, I learnt an interesting lesson…

First, I wrote it pretty simple, inheriting the widget from dijit._Widget and dijit._Templated. It had a toggle button next to its legend, which could be clicked. The toggle was a simple display none/block change.
Read more

Safari and window.open – How to do it

There is still some traffic coming in from people who are searching for how to deal with the safari popup blocker. So I thought it might be nice to also tell what you can do about it – as most people want solutions, not backgrounds…

So, here you go:

It’s pretty simple, really. What to do? Well, call window.open() while the popup blocker still allows it, and store a reference to the window object. Then, later, do with it what you want. That is, changing the location in most cases.
Read more

dojox.analytics.Urchin for jQuery

Or: Still ending the ga.js wait…

It has become quiet here the last weeks – due to an awesome trip to Italy. Returning home, I decided to put Google Analytics on this page.

As I always hate waiting for the ga.js to load while visiting websites, I wanted a mechanism to delay the load of it. Why this is a good idea has been discussed often enough elsewhere, so we take it as fact. Peter Higgins once wrote such a wrapper for dojo, and as of dojo 1.3, it’s officially included in dojox (see Alex Russel’s post). But this Wordpress theme runs jQuery, and I didn’t want to have two frameworks in one website – so I searched for something that did the job for jQuery.
Read more

Static data handling in PHP

Bild 17Every now and then I stumble upon PHP Code dealing with config files. Besides being happy that people use config files (uh, yes, it happens too often that people don’t…), I am often unhappy with how they’re dealing with config files. You can find the ugliest things out there, like arrays in .php files (my favorite). However, even if config files are used, there are strange things happening to them, like being read once and serialized into a constant.

So I want to share today a very primitive static data handler that I use for quite some time now, and wich has always served me well. By static, I mean data that doesn’t change during runtime, like smtp server connection data, database connection data and the likes.

Read more