/**
      * Embed the Proxy SWF inside the div. The Proxy SWF is key to the approach as JS does not provide
      * a mechanism to communicate with 2 documents originating from different domains.
      **/
      function embedFlash() {
          var url = "SWFProxy.swf";
          var xiSwfUrlStr = "playerProductInstall.swf";
          var flashvars = {};
          var params = {};
          params.allowscriptaccess = "always";

          var attributes = {};
          attributes.id = "proxySWF";
          attributes.name = "proxySWF";
          attributes.align = "middle";
          swfobject.embedSWF(
                url, "flashContainer",
                "100%", "100%",
                "10.0.0", xiSwfUrlStr,
                flashvars, params, attributes);

      }

http://code.google.com/p/swfobject/

Javascript solution for embedding Flash in HTML

Embedding Flash Content in HTML

javascript, html, flash

JavaScript