Stacked UDI scanning

Some UDI labels split the GS1 data across two stacked barcodes — a primary carrier with the GTIN and a secondary carrier with the lot, expiration, and serial number. The app reads both halves and merges them into a single result.

1. From the Scan tab, slowly pan the camera from one half of the stacked label to the other. Each barcode flashes a confirmation as it's captured.
2. Once both halves are captured, the app aggregates the GS1 Application Identifiers and shows the merged result card with the GTIN, lot (AI 10), expiration (AI 17), and serial (AI 21) all combined.
3. Confirm the data, set the quantity, and tap Save.

If a half is missing or unreadable, tap Cancel and re-scan, or tap the manual entry option from the missing-data warning to fill the gap by hand.

The screenshot above is the merged result card after both halves have been captured. The two-pass camera pan that produces it is camera-driven and is not depicted because the live preview can't run in the screenshot harness.