Question

How do you add or subtract from a number when you click on a button. I want to simply say

if (button.click){
    num++;
}

How can I do something like that with the google apps script buttons? Things seem a bit less straightforward to me as I’ve never used a click handler. Its probably some simple thing that I’m missing. Thanks for the help.

Answer 1

please have a look at this demo code :

var sh = SpreadsheetApp.getActiveSheet();
var ss = SpreadsheetApp.getActiveSpreadsheet();
//
function move() {
   var app = UiApp.createApplication().setTitle("move test")
       .setHeight(100).setWidth(400).setStyleAttribute("background-color","beige");
   var panel = app.createVerticalPanel();
   var next = app.createButton('next').setWidth('180');
   var chkmode = app.createCheckBox("moving mode (checked = up/dwn, unchecked=L/R)").setValue(false).setName('chkmode');
   panel.add(next).add(chkmode);
   var handler = app.createServerHandler('click').addCallbackElement(panel);
   next.addClickHandler(handler);
   app.add(panel);
   ss.show(app);
 }
//
function click(e) {
  var app = UiApp.getActiveApplication();
  var activeline = sh.getActiveRange().getRow();// get the row number of the selected cell/range
  var activecol = sh.getActiveRange().getColumn();// get the row number of the selected cell/range
  var chkmode=e.parameter.chkmode;// this returns a string, that's why true is written "true" just below...
  if(chkmode=="true"){
    ++activeline
    }else{
      ++activecol} // the ++ can be before or after the var name, your choice ;-)
  var sel=sh.getRange(activeline,activecol);
  sh.setActiveSelection(sel);// make the next row or column active
  return app;
 }

EDIT : (following your secondary question) to get a Label showing the cell’s content you can use this code in the handler function :

function click(e) {
  var app = UiApp.getActiveApplication();
  var activeline = sh.getActiveRange().getRow();// get the row number of the selected cell/range
  var activecol = sh.getActiveRange().getColumn();// get the row number of the selected cell/range
  var cellvaluestring = sh.getActiveRange().getValue().toString();
  var label = app.getElementById('label');
  label.setText(cellvaluestring);
  var chkmode=e.parameter.chkmode;
  if(chkmode=="true"){
    activeline++
    }else{
      activecol++}
  var sel=sh.getRange(activeline,activecol);
  sh.setActiveSelection(sel);// make the next row active
  return app;
 }

and in the Ui definition you have to create the label like this :

   var label = app.createLabel("test Label with text that will be modified on click").setId('label');
   panel.add(label);