Hi, this is different for launching by system event 'onLaunched'. Suppose applications should open application window inside the 'onLaunched' event handler of the main page(this is Chromium way that application is launched by event.).

var onLaunched = new xwalk.app.events.Event("onLaunched");
onLaunched.addListener(function() {
  // open application window.
  app.window.open("...")
});  

In this case, the ApplicationService::Launch will open the application window.  Whereas the RunMainDocument  won't call the listener function and no window opens.