Hi @Akbulut,
Do you want to change the Barcode type within the Drop down automatically based on the barcode value?
I have made a test on my side, if you want to change the Barcode type within the Drop down automatically based on the barcode value, I afraid that there is no way to achieve your needs in PowerApps currently.
When you use the Barcode control within an app, you need to specify a Barcode type for it (e.g. UPC, code 128, etc).
If you specify UPC Barcode type for the Barcode control, you could only scan the UPC barcode with the Barcode control within your Mobile Device (could not scan other types of Barcode). So we could not detect which type it is based on the barcode value within the app.
If you would likw this feature to be added in PowerApps, please submit an idea to PowerApps Ideas Forum:
https://powerusers.microsoft.com/t5/PowerApps-Ideas/idb-p/PowerAppsIdeas
Best regards,
Kris