Oliver Steele

I’ve updated my OpenLaszlo utility grab-bag to make browser <-> applet communication even easier. How easy?

Proxies

Put this in your browser JavaScript:

[code language=”javascript”]
var gObject = {

f: function() { console.info(‘gObject.f’, arguments) }, g: function() { console.info(‘gObject.g’, arguments) }
};
[/code]

And this in an OpenLaszlo applet:

[code language=”javascript”]
var gObject = FlashBridge.createRemoteProxy(‘gObject’, [‘f’, ‘g’]);
gObject.f(1, 2);
gObject.g(3);
[/code]

When you run the applet code, it prints this to the browser console:

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Here are some of the weekend projects that I didn’t finish this year. These aren’t good enough to put on my project list or my sources page. Some of these aren’t even working, and some of them I might not finish at all (most of my weekends are spoken for). And some of them I can’t bear to look at (I’m not proud of the code, and don’t want to be judged by it…), but I’m making myself put them out there anyway. I feel bad for the neglected little things, trapped on my hard drive, and I’d like to let them see the sun, even if just briefly before they flicker out and die.

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The two times that I’ve used the WHATWG canvas element recently, I’ve wanted a canvas with string rendering. The most recent time that I’ve used the OpenLaszlo drawview class (which has substantially the same API), I’ve wanted string rendering too.

The graph in reAnimator is a drawview, but with text labels for the edges. And the graph and parse tree in the Graph and Parse tabs of reMatch both use WHATWG canvas for lines, but text for labels. (These tabs are only visible in Firefox, for now.)

TextCanvas.js implements the canvas context extended with labels, for DHTML. And “textdrawview.lzx” implements drawview extended with labels. They share the same API, so that I can write graphics libraries (such as graph drawing) that work with both DHTML and OpenLaszlo. That API is described here.

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The OpenLaszlo application below demonstrates animation along a line, a quadratic Bezier, and a cubic Bezier (the top three paths). It also demonstrates (the bottom path) animation along a path composed of multiple segments.

Drag the slider back and forth to display the point on each path at t=slider.value/100, or click the “Animate” button to animate t from 0 to 1.

I wrote this in order to animate the state markers along the edges of the graph in reAnimator. The GraphViz dot tool, which I’m using for graph layout, generates cubic beziers, so I had to write code to render and evaluate them.

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JSON for OpenLaszlo is a JSON library for OpenLaszlo.

I wrote this in order to implement my regular expression visualizer.

There’s a live example below. Clicking on a button requests some JSON text from the server and parses it on the client. The source code to the example is here.

(When it runs off my web site, the debugger in the example displays a warning about not being able to connect to the LPS server. This means that the debugger can’t evaluate expressions, as it could if you were running it off the SDK. I’m just using the debugger here to print inspectable representations of the JSON parse results, and the warning doesn’t affect this.)

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Here’s something I’ve wanted for a long time. So I finally built it. reAnimator is a tool for visualizing how regular expression engines use finite-state automata to match regular regular expression patterns against text.

This is intended to demonstrate the implementation of regular expressions. If you want to learn how to use them instead, I recommend these references instead:

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Last week I wrote a couple of tools to keep track of subversion checkins:

The Subversion Log Viewer is a master-detail list of recent subversion revisions. It’s based on the OpenLaszlo contactlist example. The nicest feature is really an afterthought: at the last moment, I added faces for authors; I think this makes projects a lot friendlier. Right now it only adds the faces to the OpenLaszlo log; let me know if you’re interested in using this for your own project, and I’ll make a public API for adding faces to a repository.

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Expialidocio.us is a tool for visualizing your del.icio.us posting activity. It displays a graph of your posting activity over time. You can select a timespan from this graph, and it will show you a tag cloud weighted by just those dates.

Expialidocio.us was inspired by a posting by Jon Udell. Coming full circle, Udell has posted since posted about this application.

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openlaszlo.rb is a Ruby library for compiling OpenLaszlo programs. I use it to build this, this, and the toolbar here. This article describes how to use it with Rake.

Update: This is now available as a gem.

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It was months in the conception, weeks in the making, and minutes in the configuration, but the OpenLaszlo project now has a blog.  That blog is intended for project-related news, announcements, documentation, and musings, posted by members of the OpenLaszlo project and some of our co-workers at Laszlo Systems. And I’ll be returning this blog to more personal and broader topics. (Those are two overlapping categories, not one.) Plenty of Laszlo and RIA stuff where it goes beyond the immediate project work, but more other topics too.

On a related topic, Laszlo Systems has launched Laszlo Mail, a high-polish web mail product focused on cross-browser portability and on user experience . I first wrote about Laszlo Mail here. Laszlo Mail is an excellent example of the kind of application that we created OpenLaszlo in order to enable.  As Jonathan Boutelle says :” It feels like a candy-coated swiss army knife, an appealing mix of aesthetics and pragmatic design.”

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