Event Registration App - No Data Sources

[ChadRobbins]

I need to build a power app that has the following features: 

1) When a user selects a Monday or Tuesday from a date picker control ("DatePicker1"), a Button control ("Button_Register") and a Label control ("Label_OpenSeats") will appear.

2a) When "Label_OpenSeats" appears, it will show the number of available seats that are left for the event.

2b) "Label_OpenSeats" should hold that value between logins from different users. Every Monday and Tuesday should have the same starting value but should have separately stored values (so if a user registers for a specific Monday, that should not affect any value of the following Monday/Tuesday/or any day other than that specific Monday).

3) When "Button_Register" is selected, it will:
3a) Decrease the number of available seats ("Label_OpenSeats") by 1.

3b) Prohibit that same user from registering for the same event.

I already did 1, 2a, and 3a. For 3b, I'd imagine I could store registered users in a collection and check if the current user is in the collection. But there would have to be a collection for each Monday and Tuesday, right? And for 2b, I'm really not sure.

Last but not least... one restriction... no data source outside of Power Apps. No storing users in a SharePoint list, Dataverse table, etc. The above tasks have to be completed using just Power Apps (Power Automate can be used).

I've tried working on the app for days, research various ways of completing the above tasks, just writing this post took a long time because I wasn't even sure how to describe what I need. Not sure I did a very good job but if you need any additional information, please let me know. Thanks!

[EddieE]

@ChadRobbins 

This sounds like a dare and/or a school assignment to me. Trying to do this without any data source/s isn't something I'd take on.

Having said that though, you could use the LoadData & SaveData functions to meet your 2b & 3b requirements, but this would be the only way I can think of to achieve this. To my knowledge, these functions only work on mobile devices so you could only use Tablets / mobile phone and not a laptop.

Also, if you were wanting to have more than one device setup collecting your data then this would be near on impossible! Power Automate may be able to do this but it would be extremely complex and just not worth doing IMO.

You may also have to consider storage / deletion of older records? If you needed copies of who attended when you could email these to yourself then delete, so you have some sort of record?

Anyway, good luck!

[ChadRobbins]

Hey @EddieE! Ha ha, no school assignment or dare! I just tried to frame it in a way that's most easily interpretable. Maybe I failed!

I can't have a data source outside of Power Apps. Can't I create a collection to store the user's email "OnSelect" of "Button_Register", then if the user selects the same date, the "Visible" property of "Button_Register" would just check that collection for that user's email address? I just don't know how to assign a collection to each Monday and Tuesday. I guess I could create a collection when a user selects a Monday or Tuesday from the datepicker control. Not sure how that would look but do either of these not sound feasible?

Hm, I'm not familiar with that process, the storage/deletion of older records. Where am I storing them? And it's not that I need to know exactly who is attending. I just need to know the number of users attending. And the app doesn't need to have the capability to look up past registered users.

Thanks for the help!

[EddieE]

@ChadRobbins 

Fair enough mate, it just sounded odd lol

Collections are just virtual data sources, meaning, if the app is closed for any reason - say someone accidentally closed the app, turned off the device, etc - then all the collection data is lost.

This is why I suggested using Load/Save data functions for every action a user has with your dataset/s. That way, if a user closes your app, the data won't be lost. You mention users logging In/Out so there's a huge potential for data to be lost from collections - depending on how you build your app.

The data that gets Saved & Loaded using SaveData / LoadData is in a special cache on the mobile device. There are size restrictions on how much data you can save but there's no real info on how big that can be, but it would be related to the free storage space on the device. This data acts like a collection so if you are familiar with those then you should be ok with it.

I guess I could create a collection when a user selects a Monday or Tuesday from the datepicker control. Not sure how that would look but do either of these not sound feasible? - Yes, this is feasible

Can't I create a collection to store the user's email "OnSelect" of "Button_Register", then if the user selects the same date, the "Visible" property of "Button_Register" would just check that collection for that user's email address?

How do you envisage your app working? Will users open it from their own device (eg phone)? If so, then you'll need some sort of data source like SharePoint. If users 'login' using a single device, say an iPad, then the Users Email address won't be accessible because the app will have already been logged in by an Admin, or someone similar - hence only the Admin email would be captured.

Can you explain the process your app will follow eg how users will use it?