Android Question NFC in background mode

[freedom2000]

Hi,
I am trying to launch an App with an NFC tag.
I started with the NFC lib and added this into the Manisfest editor :

AddActivityText(Main,
<intent-filter>
    <action android:name="android.nfc.action.TECH_DISCOVERED"/>
</intent-filter>
<meta-data android:name="android.nfc.action.TECH_DISCOVERED"
    android:resource="@xml/nfc_tech_filter" />)
CreateResource(xml, nfc_tech_filter.xml,
<resources xmlns:xliff="urn:oasis:names:tc:xliff:document:1.2">
  <tech-list>
  <tech>android.nfc.tech.NfcA</tech>
  </tech-list>
</resources>)

I have then successfully launched my app when I approach the NFC card.
But whenever my phone is locked, the App doesn't start.
Does it mean that when screen off, the NFC hardware is disabled or do I miss something ?

Thanks

 

[JordiCP]

If the tag is always the same and your phone has SmartLock and it accepts an NFC tag as a trusted device (so 3 conditions), perhaps this link can help (not tested since my device fails in the 3rd condition )

https://www.tagstand.com/blog/nfc-tags-unlock-your-android-phonehttps://www.tagstand.com/blog/nfc-tags-unlock-your-android-phone

 

[freedom2000]

Thanks you
But smart lock has been disabled for sec reason on my phone... (Company phone)

 

[Erel]

Quoting Google documentation: https://developer.android.com/guide/topics/connectivity/nfc/nfc.html
"Android-powered devices are usually looking for NFC tags when the screen is unlocked, unless NFC is disabled in the device's Settings menu."

 

[freedom2000]

Quoting Google documentation: https://developer.android.com/guide/topics/connectivity/nfc/nfc.html
"Android-powered devices are usually looking for NFC tags when the screen is unlocked, unless NFC is disabled in the device's Settings menu."

So should we understand that they do not look at NFC when screen is off ?

That's a pity
(but thank you for this interesting link)

 

[Erel]

So should we understand that they do not look at NFC when screen is off ?

Yes.

 

[inakigarm]

In the real world: I go to a gym where the the mobile can connect to gym machines via NFC for registering training in a mobile app. If the screen is off, the mobile app can't connect to the machine (NFC tag); I'd have to open screen on mobile to register to each gym machine.

 

[freedom2000]

In the real world: I go to a gym where the the mobile can connect to gym machines via NFC for registering training in a mobile app. If the screen is off, the mobile app can't connect to the machine (NFC tag); I'd have to open screen on mobile to register to each gym machine.

This is probably the only reason why I never touch a gym machine !