You should be able to do it. Here is an example panel:
<abs contexttype="opengear" gridsize="20">
<meta>
<params>
<param access="1" maxlength="0" name="URL" oid="URL" type="STRING" value="http://www.google.com" widget="text"/>
</params>
</meta>
<param height="40" left="20" oid="URL" right="101" top="20"/>
<button buttontype="push" height="40" name="Go" right="21" top="20" width="80">
<task tasktype="ogscript">ogscript.getComponentsById('browser')[0].setUrl(params.getValue('URL', 0));</task>
</button>
<browser bottom="10" id="browser" left="10" right="10" top="80" url="http://www.rossvideo.com"/>
</abs>
If your URL has quotes in it, it may screw up the URL. You may have to escape them somehow.
#DashBoard