Metal Hurlant

Back in the days, Netscape created this neat layer of glue called LiveConnect. Among other things, it would expose javascript objects to Java through a JSObject class.
Fast forward to ActionScript. ExternalInterface provides a way of eventually doing the same thing. Things like FABridge make things somewhat friendlier, but FABridge only deals with accessing ActionScript goodies from JavaScript.

So here’s JSObject. Yes, same name. In fact, it behaves remarkably similarly like its Java counterpart: Get a handle to the browser window, and climb up the DOM from there. However, it distinguishes itself by its transparent syntax.
To the untrained eye, it looks like your javascript objects have been carried over inside the Flash player.
For example, you can do this with it:

[code lang=”actionscript”]
with (JSObject.getWindow()) {
e = document.getElementById(”test”);
b = document.createElement(”button”);
b.innerHTML = “Click me!”;
b.onclick = function(e:*):void {
alert(”clicked on “+this+” at “+e.clientX+”,”+e.clientY);
};
document.body.insertBefore(b,e);
}
[/code]
Except for the typing of the function parameter and return value, there is no difference between this and browser javascript code.
Even neater, if you put a breakpoint inside that code, you can browse through JSObject instances and effectively walk your browser DOM through the flash debugger.
There’s a lame demo that uses the above example.. You should probably browse the source view, though.
At the risk of giving away the ending, this is done by coupling flash.utils.Proxy with ExternalInterface, with a fair amount of javascript glue on the browser side.
It has various performance limitations, but hopefully that can be minimized over time.

Also, I’ve added another compiler to the as3 eval() project. This one is just a straight linkage of the ESC abc files, as made available through the tamarin-central repository. It works, but it’s not particularly more interesting than the AS3 version, for now. However, as time goes by, and the ESC stuff improves, it will be a cheap way to see those improvements in a pretty web UI, without some codemonkey having to port the darn thing over and over again.

Well that’s it for now. Eval and JSObject.. I wonder where I’m going with this.

Explore posts in the same categories: web, flash, actionscript, eval

This entry was posted on Friday, January 4th, 2008 at 3:24 am and is filed under web, flash, actionscript, eval. You can comment below, or link to this permanent URL from your own site.