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Dusko Licanin
SaaS MVP Developer for Founders | Web & Mobile Apps
A push notification model usually breaks in one of two ways: a second phone stops receiving anything, or notifications keep arriving for the account that just signed out. Both come from storing one push address per user. Store one row per app installation instead, with the user...
duskolicanin.com
Keep Flutter Push Tokens Correct Across Devices
Fix Flutter push notifications that miss a second device or follow the previous user: store one FCM installation ID per device and prune unregistered IDs.
One walk through Pasadena. Two ways to design it.
A: Field Guide, with the map up front.
B: Departure Board, with the itinerary up front.
Same places, same features. Which would you choose: A or B?
Download the Flutter source code for both versions for free.
https://contra.com/products/7ySCJSxh-switchback-two-flutter-app-designs
4 voted
50%
4 voted
50%
8 votes
Closed
Each stock adjustment should get its ID when the person taps Confirm and keep it through every retry, because the Firestore transaction recognizes a repeated write only by finding that ID already recorded.
duskolicanin.com
Build a Flutter QR Inventory Scanner Without Duplicates
Stop duplicate stock entries from a Flutter QR scanner: lock detections until the user confirms, validate the payload, and retry Firestore writes with one ID.
Because Firestore evaluates security rules on the server, a write queued offline can be refused after reconnection, so hold the saved label until a snapshot shows hasPendingWrites and isFromCache both false, which your listener sees only with includeMetadataChanges: true.
