google apps script - Function getUi not found in object Form

Question

I'm trying to create a function that's trigerred when its container-bound Form is submited, then retrieves some cells from a spreadsheet and display them to the Form's user in an alert window.

Here's the code :

function displayResult() {
var sheet = SpreadsheetApp.openById("mySheetID");
var lastrow = sheet.getLastRow();
var range = sheet.getRange("BI" + lastrow + ":BM" + lastrow);
var values = range.getValues();
var form = FormApp.getActiveForm();
var ui = form.getUi();
ui.alert('values[0][0]');
}

Nothing happens on Form submission and I'm getting the following error message :

TypeError: Function getUi not found in object Form. at displayResult(Code:7)

Answer 1

Unsolvable problem : As Sandy Good said, custom dialogs do not work on a Google Form except when the Form is in Edit mode.