How to Change the QR code Status into "Already Used!" or "Already Scanned!"

Questions about Thunkable
, ,
1

help with this "if QR code is scanned from your App, if will change the status of your QR Code “Already Scanned!” or “Not Valid! Create a new One”

Thanks.

1 Like
2

https://chart.apis.google.com/chart?cht=qr&chl=[content]&chs=300x300
Content can use com.gmail.xxxxxx.app_name.text
Ex.
App id:com.gmail.1234.qrapp
text: hello
QR code:
https://chart.apis.google.com/chart?cht=qr&chl=com.gmail.1234.qrapp.hello&chs=300x300
:grinning:
圖片

3

If QR code return contain com.gmail.1234.qrapp

`x=replace com.gmail.1234.qrapp`
`if x==hello`
   `Show label text=hello`
`if x==...`
   `then`

...

4

Hi tony,

This is what I wanted to achieve:

My app shows a QR code (a dynamic QR Code). When another person scan it either using their own phone, code scanner or even any scanning machine from a cash register shall we say McD**, it will say the status of the QR code “Not Valid!” or even generate a new QR Code.

5

QR codes are just shortcuts to content such as text or URLs. So I think the only way to do what you’re asking is to have the QR code point to a URL that has a page that gets updated when it’s visited.

So I guess you’d need a unique URL (say, a Firebase key value) that when visited changes the value of the data source. All of this would be done outside of Thunkable. So it’s not something I can help with as I suspect it requires some HTML coding of some sort.

It would be something like:

When web page loads
   Display firebase key (e.g. "unused")
   Change firebase key (e.g. to "already used")
1 Like
6

Thank you for your input Tatiang, I will look into that stream.