Re: NfcMessageData

Hi Don,

Thank you for the feedback. I am sorry to be a bit late to announce
that the spec has been pulled from under you, and there is a new
draft.

On Mon, Dec 15, 2014 at 11:17 PM, Don Coleman
<dcoleman@chariotsolutions.com> wrote:
> http://w3c.github.io/nfc/index.html#the-nfcmessagedata-interface
> Does the NfcMessageData.arrayBuffer contain the raw bytes for the NDEF
> record?

No.

>
> Does the NfcMessageData.blob contain only the payload data?

Yes.

>
> How do I get additional TNF and/or Record Type data from the NfcMessageData
> to interpret the Blob? For these 2 records, I'd need different logic to
> parse the payload into something usable.
>
>    TNF: 4 (External)
>    Type: example.com:patientRecord
>    Payload: <some binary content>
>
>    TNF: 2 (Media-type)
>    Type: text/led
>    Payload: <some binary content>
>
> Will TNF External (TNF=4) records end up as a Blob?

Yes.
I was under the impression this (TNF=4) was also listed in section
6.1. but it's not. I will fix this.

When reading NFC data, implementations will have the full NDEF
records, and can do a translation to NfcMessageData. They can use
NfcMessageData.contentType (e.g. application/octet-stream) in order to
indicate the type of content delivered to applications.

When writing data, NfcMessageType needs to be translated to NDEF
records by the implementation. Perhaps we could to list recommended
mappings (like with read), but as a first draft, I thought it can be
regarded as an implementation detail.

Best regards,
Zoltan

Received on Tuesday, 16 December 2014 11:10:28 UTC