Question

I have a Google Apps Script that dynamically generates buttons and assigns for each a ClickHandler which in turn calls a function.
My problem is that because every button calls the same function I can’t find a way to indentify which of them actually made the call. Here is a code sample:

var handler = app.createServerHandler("buttonAction");
for (i=1,...) {
  app.createButton(...).setId(i).addClickHandler(handler);
}
function buttonAction() {
  //How do I know what button made the call?
}

Answer 1

Another option is to use the e.parameter.source value to determine the ID of the element that triggered the serverHandler to be called.

Here’s an example:

function doGet(e) {
  var app = UiApp.createApplication();
  var handler = app.createServerHandler("buttonAction");

  for (var i = 0; i < 4; i++) {
    app.add(app.createButton('button'+i).setId(i).addClickHandler(handler));
  }
  return app;
}


function buttonAction(e) {
  var app = UiApp.getActiveApplication();
  Logger.log(e.parameter.source);    
}

e.parameter.source will contain the ID of the element, which you could then use to call app.getElementById(e.parameter.source) …