Create a seat booking form with Google Forms, Google Sheets and Google Apps Script

Google Forms, Google Sheets, Google Apps Script: SpreadsheetApp, FormApp

In this tutorial, we are going to build a simple seat booking Google Form. It will contain a registeree’s name and the session that they wish to attend.

Each time a registeree submits a request to book a seat for a session, that seat is taken from the list displaying only the remaining seats for that session for when the next user submits the form.

Take a look at the example below (click to expand the image):

Basic Seat Booking Form Google Forms

If all the seats have been booked for a seminar, then that seminar will not appear on the form. If all seats have been booked for all seminars, then the Google Form will close.

We will even create a  live list of attendees that we can embed on our website using Google Sheets.

Google Forms can’t do this for you out of the box. We will need to use Google Sheets to store our bookings and do some manipulation of the data. Then, we will use Google Apps Script to update the Google Form with the number of seats each time the form is submitted.

The Google Apps Script script has been prepared in a way that someone with limited coding skills can use it as a template by plugging in a few global variables. Alternatively, a more advanced user can incorporate the code into a larger project.

I’ll assume you have the basic abilities to create a simple Google Form and have used Google Sheets.

This tutorial can be followed as a useful step-by-step guide or if you are more confident, you can simply jump to the code using the contents below.

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Google Apps Script: How to force subscribe Google Group Members to a Google Calendar for G Suite [Update 06 Apr 2022]

Google Apps Script, G Suite Admins, Google Calendar, Calendar API,  AdminDirectory, GroupsAp

Note! This approach no longer force subscribes users to a Calendar. The new approach can be found here. [update 06 Apr 2022]

It appears that the approach below no longer force-subscribes users in a Group to a calendar. Google Made this change in March of 2020, some 7 months after the post was written.

Service accounts created on or after March 2, 2020 are only able to invite guests using domain-wide delegation of authority .

There is also a note in the Sharing Calendars chapter of the Calendar API information stating:

Note: Sharing a calendar with a user no longer automatically inserts the calendar into their CalendarList. If the user should be able to see and interact with the shared calendar, you will also need to call the CalendarList: insert() method.

While this explanation is no doubt helpful for general use, using the insert() method in CalendarList requires that the script be run by the user that needs to be shared.

One hint to a workaround can be found in the update notes referring to the ability to invite guests using domain-wide authority using a service account.

This is a pretty gnarly process to set up and write about and has taken some time to write about and test, but you can now find the tutorial here:

Having said all that, the script below does still contain some interesting use cases for using the Admin SDK service and Advanced Calendar API service in Google Apps Script, so I will leave it up until I can publish a solution.

The script below can now be modified to to extract the users in a group and then use a Service Account on each user to force subscribe them using the code in the tutorial link above.

Big thanks to Jeremy for bringing this to my attention and apologies, I could not find a quick fix.

~ Yagi 06 April 2022

Note! This article is for G Suite users and admins. You won’t be able to apply the same code to Consumer accounts. 

Google Groups in  G Suite can be a really convenient and clean way to share users to drive folders and file locations, email users and set up Google+ community locations. However, I have come across some issues with sharing Google Calendar to Google Groups.

When you assign a Google Group email to a Google Calendar it sends out an email inviting the users in the group to accept the calendar into their list of shared calendars. The user must then accept the invitation before the calendar is added to their Google Calendar list of shared calendars…calendar.

The users receive an email message like this:

Hello Goat_GroupAlpha,

We are writing to let you know that has given you access to view events on the Google Calendar called “Test”.

Click this link to add the calendar.

– The Google Calendar Team

The Problem

In a large organisation, not all users in a group will add the calendar using the link. This might be okay but if the calendar is important or the user, as is often the case, simply just forgot to add it, then there will be emails to you the admin in the future asking you why they don’t have the calendar that everyone else has and has now missed some important event…sigh.

Another issue is that when a new user is added to a group when the group has already been added to a calendar, then that user will not receive an email invitation to the calendar and won’t be able to see the calendar.

Almost a Solution

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Google Apps Script: Google Standard Color Palette Picker for Sidebar and Dialog Boxes in Google Sheets, Google Docs and Google Slides (Updated Feb 2022)

Google Apps Script: Dev Tools, Color Picker, Side Bar, Custom Prompt, HtmlService, onOpen, Sidebar, Dialog Box

I wanted to update one of my free Google Add-on apps that works with colour. What I had is just the standard HTML color input element where the user selects from the palette and that hexadecimal colour code is returned to Google Apps Script to be used in the App. The problem is that it is really hard to get a good colour match between the palette and Google’s own colour range that is accessible from the fill or text colour buttons.

Take a look at the comparison between the HTML color input element and the Google Sheet background colour palette in the image below.

Color input vs google sheet palette colours

That’s not a user-friendly tool to match colours with the standard Google palette.

So in the back of my mind, I had always wanted to create a tool for a sidebar or dialogue box that would allow the user to easily access the standard colours or use the custom palette provided by the HTML color input.

After finding a bit of time in my recent summer break I came up with this.

Google Color array picker

And this is how it looks in action:

(Note: add-ons has been updated to Extensions)

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Google Apps Script: Create a Select All Checkbox to Tick Checkboxes in Any Desired Range in Google Sheets

Google Apps Script: isChecked(), switch, filter, map

One Checkbox to Rule them All

Now that’s a fantasy novel I could be my gums into.

Have you ever created a Google Sheet projects where you could really use a select all checkbox (they call them ‘Tick-boxes’ in Google Sheets)? Sure you can copy a range of tickboxes and paste the same range etc. But can you really trust your users not to mess that up?

People are used to select-all checkboxes in their computerised lives. It’s always better to work with familiarity to provide a better user experience rather than try and teach the user on the fly how to do something your way.

With this in mind, I went about creating a select-all checkbox for Google Sheets. Here is a little demo of how it all works. All the black background Tick boxes are select All boxes. These boxes have been assigned a range of other checkboxes that will be either checked or unchecked depending on the main select-all boxes state.

Google Select All Demo with Google Apps Script
Select All Demo

As you can see, the select all checkbox only changes the tick boxes in the assigned range. It does not affect any other non-tick box data in the same range.

To get this up and running on your own project, all you need to do is copy and paste in the two code files in your Google Apps Script editor. The first code file is the function that runs the check-all code. The other file stores all the select-all checkboxes and the ranges that they will affect.

Let’s take a look at the code and then run through a quick use guide before finishing off with an example.

Those of you who want to dive into the nuts and bolts of the code, there will be more explanation of each element of the code at the end.

The Code

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Google Apps Script: How to check if there is a Tick Box (Check Box) in a cell or range

Google Apps Script: checkbox, Google Sheets

This is something  I came across today when working on a project. I needed my Google Apps Script to look at a cell or range and determine whether there is a checkbox in that Google Sheet cell. If there is, then my script would do something. Otherwise, I would throw an error alert to the user.

Off I went searching through the Google Apps Script docs hoping to find something like an isCheckbox() method.

No such luck on such an obvious solution, but after playing around with some of the other checkbox methods, I did find a solid alternative.


I didn’t feel that the docs were up to their usual amazing standard here. Thus the explanation below (Yes, I am also procrastinating from my project, but I’m also making an online note for myself).

isChecked() takes a range or a cell and returns:

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