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No NFC events after lock-screen RRS feed

  • Question

  • Situation:

    • App has subscribed for NFC events
    • User taps NFC tag - app receives event
    • User locks the screen - app stops subscribing for NFC
    • User unlocks the screen - app re-starts subscribing for NFC events
    • User taps NFC tag

    Expected result: app receives NFC event
    Actual result: app does not receive NFC event

    This behaviour worked in WP 8.0, but seems to be broken in WP 8.1 / 8.1 Update DP. It affects both Silverlight 8.0, as well as 8.1 Universal Apps. Receiving events works again after re-starting the app.

    Details: according to the SDK documentation, it should not be necessary to stop and re-subscribe for NFC events. However, it does not work in any case.

    Steps to re-produce: This can easily be re-produced by running the Proximity Sample from: http://code.msdn.microsoft.com/windowsapps/Proximity-Sample-88129731 - choose action "4) Display ProximityDevice events" and execute the steps above. After the screen has been locked / unlocked, the device does not receive events anymore.

    I've also created a sample myself, which listens to the visibility changed events to (re)activate NFC when the app loses visibility due to the lock screen. However, this also does not help to make the phone read NFC messages again: http://1drv.ms/1qLgsRN

    Tested on: Nokia Lumia 930, OS: 8.10.14157.200, FW: 02061.00066.14252.51001, Lumia Cyan.
    Also reproduced on Nokia Lumia 820 with WP 8.1.

    Issue not present on Lumia 820 with WP 8.0.

    Wednesday, September 10, 2014 2:09 PM

All replies

  • Is there already a solution for the problem mention above?
    Friday, January 2, 2015 11:09 PM
  • Unfortunately still no update or known workarounds - it's a major issue / blocker for many NFC apps.

    Can still be easily reproduced on Lumia 930 with OS 8.10.14226.359 & Lumia Denim.

    Tuesday, February 24, 2015 1:12 PM