Scanner external object

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Scanner external object enables to programmatically scan barcodes (2D and QR Codes) using the device's camera.
See also Scanner Control to associate an Edit control (attribute or variable) the possibility to enter barcode information to the field directly from the camera.

Scannerexternalobject-Location_png image_201861294135_1_png


It does not have any.


ScanBarcode method

Scans a linear barcode or QR code and optionally filters a specific list of Barcodes.

Return value VarChar(200)
Parameters [ barcodeTypes:Collection(BarcodeTypes) ]

Read more in HowTo: Use ScanBarcode method from Scanner external object in Native Mobile applications.

ScanInLoop method

Scans several barcodes at once, optionally using a specific list of barcodes. User intervention is not required until it decides to stop reading.

Return value ScannedBarcodes
Parameters [ beepOnEachRead:Boolean ] [ , barcodeTypes:Collection(BarcodeType) ] 

Read more in HowTo: Use the ScanInLoop method from Scanner external object in Native Mobile applications.


It does not have any.

Code example

In the shopping cart scenario, suppose we have a Scan button in the Layout, to read a product barcode, add it automatically to the cart and finally edit the product in the cart to show the product info and to indicate the quantity:

Event 'Scan'
    &ScanBarcode = ScannerAPI.ScanBarcode(&EANBarcodeTypes)
    &CartItemId = CartItem_InsertButNotConfirmed(&ScanBarcode,&Messages)
    WorkWithDevicesCartItem.CartItem.Detail(&CartItemId, &ScanBarcode)


BarcodeType domain

Supported barcode types.

Aztec Aztec code linear barcode.
Code128 Code 128 linear barcode.
Code39 Code 39 linear barcode.
Code39Mod43 Code 39 mod 43 linear barcode.
Code93 Code 93 linear barcode.
DataMatrix Data Matrix 2D barcode.
EAN_13 European Article Number 13 digits code  linear barcode.
EAN_8 European Article Number 8 digits code linear barcode.
Interleaved2of5  Interleaved 2 of 5 code linear barcode.
ITF14 ITF-14 code linear barcode.
PDF417 PDF147 code 2D barcode.
QR QR code 2D barcode.
UPC_E UPC-E linear barcode.

Structured Data Types


  • Collection( Barcode:VarChar(200) )
    A set of scanned barcodes values.


The device camera can be used in multiples scenarios in order to enter information more easily without the user requiring typing; for instance:

  • Retrieve store's product information from its linear barcode and adding to the shopping cart (app example: Tienda Inglesa)
  • Add contact information reading personal cards/tags including QR Codes (app example: GeneXus Event)
  • Read a sequence of several codes (linear or QR codes) until the user decides to stop reading. This can be useful to emulate a supermarket cashier.


Generators:  AndroidApple


This external object is available since GeneXus X Evolution 2 Upgrade 3.

See also