       domain: "kopi.com"
     tracker.load()
     tracker.pageview("/xs/46/")
-    tracker.event("book", "download", )
+    tracker.event("book", "download", "1")
   ###
   class Tracker
 

      s.parentNode.insertBefore(ga, s)
      return

    setVar: (slot, key, value, level=kls.PAGE_LEVEL) ->
      win._gaq.push ['_setCustomVar', slot, key, value, level]
      this

        slot++
      this

    ###
    Track page view
    ###
    pageview: (url) ->
      logger.info "Track page: #{url}"
      win._gaq.push ["_trackPageview", url]
      return

    ###
    Track event
    ###
    event: (category, action, label="", value=0) ->
      logger.info "Track event: #{category}:#{action}:#{label} (#{value})"
      win._gaq.push ["_trackEvent", category, action, label, value]
