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I wrote up two different ways to do this, using either a List Picker or just a few Buttons.
The List Picker option allows you to add any number of scans, you can even write it up so that the end user can decide how many and what to name the scans(on a setup page) That's part of the power of using Lists, they can grow and be changed by the user and not be hard coded.
Here we make up two lists, one for the Names of the Scans and the other for the results.
In Screen1.Initialize we link the List Picker to the List of Names, it will automatically update as needed.
When you press the Scan Button it shows you the list of items to scan, (in a final program I would have it update the list to something like 'Code1:empty' 'Code2:1234' so the user doesn't have to remember what is what sense you can't see the main screen.)
Do the Scan and Display the results.
When the btnNewItem is pressed, save your work and reset things.
The Source Code:https://sites.google.com/site/blocks123/bar-code-scanner/ListBarcode_One.zip
The Buttons is easier, but it must be hard coded, so if you know just what you want it can be set up like this.
The Source Code:https://sites.google.com/site/blocks123/bar-code-scanner/ListBarcode_Buttons.zip
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