I am using a Bar-code scanner on my mobile app (Android) to update items at a remote server. The user can either want to scan to increase the item's quantity by 1 or decrease by 1 each time they scan.
I wanted to be able to straight away scan the item 10 times and increase the item quantity by 10. This doesn't work as each time a single scan is made, the page switches out of the Bar-code scanning page to previous page. So I got to make do with 1 item scan at a time, go back to previous page and come back again for 2nd scan and so on.
Concept One - 1 way I could go about it is to make a main page with 2 separate buttons, 1 for "scan to add" and another for "scan to remove".
Pressing 'scan to add' would divert me to "ADD" page with a button. Clicking the button activates the scanner where I scan 1 at a time, update the server and go back to the "ADD" page again.
Same for the 'scan to remove' where it will have moved the user to a "REMOVE" page with a button.
I just don't find the concept of an entire page with 1 button appealing.
Another way is to have a single "Bar-code Scanner" button on the main page which immediately brings user to the scanning page where they scan item. Upon scanning, a Dialogue box appears asking to "add or remove"? Once the user chooses, item is updated and back to main page.
I feel both ways looks cumbersome and not user friendly. Is there any better way to tackle this? I am not even able to find applications with similar situation to compare and find ideas.