How do I modify a button from a function in Google Apps Script UI App

I have created a UI App Form Panel in Google Apps Script with the following following button definition:

  var voteButton = app.createButton('Submit');
  var handler = app.createServerClickHandler('buttonPressed');
  handler.addCallbackElement(formContent);
  voteButton.addClickHandler(handler);

the severClickHandler is set to call the following functio开发者_运维问答n:

buttonPressed(){
   //do something .....
}

This works well, but I need to disable the voteButton once the execution og the buttonPressed() function is completed successfully. How can set voteButton to not visible. Is there a way I can pass the vote button to the buttonPressed function?

Jesse, over at the Google App Script forum, has answered this question: Server Click Handler