Webmaster Forum / HTML, CSS, Scripts / JavaScript / November 2005

I do not think it is possible to resolve that contradiction.
You have to decide what is more important to your task.

No, ECMAScript implementations like JavaScript 1.5+ (Mozilla/5.0)
and JScript 5.5+ (IE/5.5+) are single-threaded.

PointedEars

[snip]

There are only two hacks I can think of which might help:-

1.    If you are using the HTTPRequest object to download the XML file,
this can be set to synchronous or asynchronous (i.e. the function that
called the HTTPRequest can still keep running) download.

2.    You could spawn a pop-up window/modeless dialogue box or
IFRAME(?) to do the download, as these are in some implementations
effectively a separate thread.

For instance, I use a pop-up window to provide a progress bar for a
function in the parent window.  The parent window function can send an
update to the pop-up window without interrupting the parent window
function.

Regards

Julian Turner

These are mutually exceptive requirements: the whole idea of
synchronized method (not in JavaScript only) is that the program flow
doesn't proceed until the method has returned the result. A
synchronized method that allows the sequent statements executions w/o
waiting for results is a non-sense (it is not synchronized then).

What you really want I guess is to prevent data access until new data
is ready. This is usually achieved by setting and checking flags.

Pseudo-code:

if (data update needed) {
glbFlagDataState = 'updating';
make XMLHttpRequest with callback function itsDone;
}

function itsDone() {
glbFlagDataState = 'ready';
}

function usingData() {
if (glbFlagDataState == 'ready') {
 // do what you want
}
else {
// try your luck on the next system tick:
setTimeout(usingData);
}
}

install an infinite bandwidth connection between the cient machine and the
server. :) , live with the delay, or figure out how to do it asynchronously.

possibly.

Bye.
  Jasen