This is a short example on calling javascript from flex using ExternalInterface…
Application - Source
Please Note:  Javascript has to be on in your browser and the javascript is in the html-template > index.template.html file.

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The syntax is a little tricky but I found it on the google groups, by searching “get a markers latitude”
marker.getPoint().lat();
it’s very tricky because there isn’t a ton of documentation that show examples of this.

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This function does an alert on what you request… it’s a great little function picked it up from
activsoftware.com

function getQueryVariable(variable) {
var query = window.location.search.substring(1);
var vars = query.split(“&”);
for (var i=0;i<vars.length;i++) {
var pair = vars[i].split(“=”);
if (pair[0] == variable) {
return pair[1];
}
}
alert(’Query Variable ‘ + variable + ‘ not found’);
}
Call a page, page.html?x=test
alert( getQueryVariable(“x”) );

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