Added in API level 14
Deprecated in API level 29

CreateNdefMessageCallback

interface CreateNdefMessageCallback
android.nfc.NfcAdapter.CreateNdefMessageCallback

A callback to be invoked when another NFC device capable of NDEF push (Android Beam) is within range.

Implement this interface and pass it to NfcAdapter#setNdefPushMessageCallback setNdefPushMessageCallback() in order to create an NdefMessage at the moment that another device is within range for NFC. Using this callback allows you to create a message with data that might vary based on the content currently visible to the user. Alternatively, you can call setNdefPushMessage setNdefPushMessage() if the NdefMessage always contains the same data.

Summary

Public methods
abstract NdefMessage!

Called to provide a NdefMessage to push.

Public methods

createNdefMessage

Added in API level 14
abstract fun createNdefMessage(event: NfcEvent!): NdefMessage!

Deprecated: Deprecated in Java.

Called to provide a NdefMessage to push.

This callback is usually made on a binder thread (not the UI thread).

Called when this device is in range of another device that might support NDEF push. It allows the application to create the NDEF message only when it is required.

NDEF push cannot occur until this method returns, so do not block for too long.

The Android operating system will usually show a system UI on top of your activity during this time, so do not try to request input from the user to complete the callback, or provide custom NDEF push UI. The user probably will not see it.

Parameters
event NfcEvent!: NfcEvent with the NfcEvent.nfcAdapter field set
Return
NdefMessage! NDEF message to push, or null to not provide a message