Before using the BarcodePicker, you must set the application key to the key you have obtained from the Scandit website. If you do not do this, license registration will fail and you will not be able to use the barcode picker. Setting the license key itself does not activate the device yet. Device activation only happens when a barcode picker is used for the first time. So it is safe to set the license key at application start, irrespective of whether the user is going to scan barcodes or not.

Note that currently it is not possible to change the app key after a picker has been instantiated. Only the app key set when the first picker is instantiated will be used. You will have to close the application and restart it before changing the app key.

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