# DiscoverySessionCallback
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
# DiscoverySessionCallback
*** ** * ** ***
Kotlin\|[Java](https://developer.android.com/reference/android/net/wifi/aware/DiscoverySessionCallback "View this page in Java")
```
open class DiscoverySessionCallback
```
|---|----------------------------------------------------------------------------------------------------------------------------------------------------|
| [kotlin.Any](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-any/index.html) ||
| ↳ | [android.net.wifi.aware.DiscoverySessionCallback](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#) |
Base class for Aware session events callbacks. Should be extended by applications wanting notifications. The callbacks are set when a publish or subscribe session is created using[WifiAwareSession.publish(PublishConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#publish(android.net.wifi.aware.PublishConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler))or[WifiAwareSession.subscribe(SubscribeConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#subscribe(android.net.wifi.aware.SubscribeConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler)).
A single callback is set at session creation - it cannot be replaced.
## Summary
| Public constructors ||
|------------------------------------------------------------------------------------------------------------------------------------------------------------------|---|
| [DiscoverySessionCallback](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#DiscoverySessionCallback())`()`
|
| Public methods ||
|----------------------------------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onBootstrappingFailed](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onBootstrappingFailed(android.net.wifi.aware.PeerHandle))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`)` Callback indicating that a Bootstrapping method negotiation failed. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onBootstrappingSucceeded](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onBootstrappingSucceeded(android.net.wifi.aware.PeerHandle,%20kotlin.Int))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`, `method:` `[Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html)`)` Callback indicating that a Bootstrapping method negotiation succeeded. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onMessageReceived](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onMessageReceived(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)!`, `message:` `[ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!`)` Called when a message is received from a discovery session peer - in response to the peer's[DiscoverySession.sendMessage(PeerHandle, int, byte[])](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#sendMessage(android.net.wifi.aware.PeerHandle,%20kotlin.Int,%20kotlin.ByteArray)). |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onMessageSendFailed](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onMessageSendFailed(kotlin.Int))`(`messageId:` `[Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html)`)` Called when message transmission initiated with[DiscoverySession.sendMessage(PeerHandle, int, byte[])](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#sendMessage(android.net.wifi.aware.PeerHandle,%20kotlin.Int,%20kotlin.ByteArray))fails. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onMessageSendSucceeded](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onMessageSendSucceeded(kotlin.Int))`(`messageId:` `[Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html)`)` Called in response to[DiscoverySession.sendMessage(PeerHandle, int, byte[])](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#sendMessage(android.net.wifi.aware.PeerHandle,%20kotlin.Int,%20kotlin.ByteArray))when a message is transmitted successfully - i. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onPairingSetupFailed](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onPairingSetupFailed(android.net.wifi.aware.PeerHandle))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`)` Callback indicating that a pairing setup process failed. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onPairingSetupRequestReceived](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onPairingSetupRequestReceived(android.net.wifi.aware.PeerHandle,%20kotlin.Int))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`, `requestId:` `[Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html)`)` Callback indicating that a pairing request is received from peer. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onPairingSetupSucceeded](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onPairingSetupSucceeded(android.net.wifi.aware.PeerHandle,%20kotlin.String))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`, `alias:` `[String](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html)`)` Callback indicating that a pairing setup process succeeded. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onPairingVerificationFailed](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onPairingVerificationFailed(android.net.wifi.aware.PeerHandle))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`)` Callback indicating that a pairing verification process failed. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onPairingVerificationSucceed](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onPairingVerificationSucceed(android.net.wifi.aware.PeerHandle,%20kotlin.String))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`, `alias:` `[String](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html)`)` Callback indicating that a pairing verification process succeeded. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onPublishStarted](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onPublishStarted(android.net.wifi.aware.PublishDiscoverySession))`(`session:` `[PublishDiscoverySession](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishDiscoverySession)`)` Called when a publish operation is started successfully in response to a[WifiAwareSession.publish(PublishConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#publish(android.net.wifi.aware.PublishConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler))operation. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onServiceDiscovered](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)!`, `serviceSpecificInfo:` `[ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!`, `matchFilter:` `[MutableList](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-mutable-list/index.html)<[ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!>!`)` Called when a subscribe operation results in a service discovery. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onServiceDiscovered](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.ServiceDiscoveryInfo))`(`info:` `[ServiceDiscoveryInfo](https://developer.android.com/reference/kotlin/android/net/wifi/aware/ServiceDiscoveryInfo)`)` Called when a subscribe operation results in a service discovery. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onServiceDiscoveredWithinRange](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscoveredWithinRange(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList,%20kotlin.Int))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)!`, `serviceSpecificInfo:` `[ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!`, `matchFilter:` `[MutableList](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-mutable-list/index.html)<[ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!>!`, `distanceMm:` `[Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html)`)` Called when a subscribe operation results in a service discovery. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onServiceDiscoveredWithinRange](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscoveredWithinRange(android.net.wifi.aware.ServiceDiscoveryInfo,%20kotlin.Int))`(`info:` `[ServiceDiscoveryInfo](https://developer.android.com/reference/kotlin/android/net/wifi/aware/ServiceDiscoveryInfo)`, `distanceMm:` `[Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html)`)` Called when a subscribe operation results in a service discovery. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onServiceLost](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceLost(android.net.wifi.aware.PeerHandle,%20kotlin.Int))`(`peerHandle:` `[PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)`, `reason:` `[Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html)`)` Called when the discovered service is not available. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onSessionConfigFailed](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onSessionConfigFailed())`()` Called when a publish or subscribe discovery session cannot be created:[WifiAwareSession.publish(PublishConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#publish(android.net.wifi.aware.PublishConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler))or[WifiAwareSession.subscribe(SubscribeConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#subscribe(android.net.wifi.aware.SubscribeConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler)), or when a configuration update fails:[PublishDiscoverySession.updatePublish(PublishConfig)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishDiscoverySession#updatePublish(android.net.wifi.aware.PublishConfig))or[SubscribeDiscoverySession.updateSubscribe(SubscribeConfig)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeDiscoverySession#updateSubscribe(android.net.wifi.aware.SubscribeConfig)). |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onSessionConfigUpdated](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onSessionConfigUpdated())`()` Called when a publish or subscribe discovery session configuration update request succeeds. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onSessionTerminated](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onSessionTerminated())`()` Called when a discovery session (publish or subscribe) terminates. |
| open[Unit](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-unit/index.html) | [onSubscribeStarted](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onSubscribeStarted(android.net.wifi.aware.SubscribeDiscoverySession))`(`session:` `[SubscribeDiscoverySession](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeDiscoverySession)`)` Called when a subscribe operation is started successfully in response to a[WifiAwareSession.subscribe(SubscribeConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#subscribe(android.net.wifi.aware.SubscribeConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler))operation. |
## Public constructors
### DiscoverySessionCallback
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
DiscoverySessionCallback()
```
## Public methods
### onBootstrappingFailed
Added in[API level 34](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onBootstrappingFailed(peerHandle: PeerHandle): Unit
```
Callback indicating that a Bootstrapping method negotiation failed.
| Parameters ||
|--------------|----------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):The bootstrapping peer handle This value cannot be`null`. |
### onBootstrappingSucceeded
Added in[API level 34](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onBootstrappingSucceeded(
peerHandle: PeerHandle,
method: Int
): Unit
```
Callback indicating that a Bootstrapping method negotiation succeeded. The follow-up out-of-band bootstrapping can start
| Parameters ||
|--------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):The bootstrapping peer handle This value cannot be`null`. |
| `method` | [Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html):The bootstrapping method accept by the peer Value is either`0`or a combination of[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_OPPORTUNISTIC](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_OPPORTUNISTIC:kotlin.Int),[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_PIN_CODE_DISPLAY](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_PIN_CODE_DISPLAY:kotlin.Int),[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_PASSPHRASE_DISPLAY](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_PASSPHRASE_DISPLAY:kotlin.Int),[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_QR_DISPLAY](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_QR_DISPLAY:kotlin.Int),[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_NFC_TAG](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_NFC_TAG:kotlin.Int),[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_PIN_CODE_KEYPAD](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_PIN_CODE_KEYPAD:kotlin.Int),[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_PASSPHRASE_KEYPAD](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_PASSPHRASE_KEYPAD:kotlin.Int),[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_QR_SCAN](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_QR_SCAN:kotlin.Int), and[android.net.wifi.aware.AwarePairingConfig#PAIRING_BOOTSTRAPPING_NFC_READER](https://developer.android.com/reference/kotlin/android/net/wifi/aware/AwarePairingConfig#PAIRING_BOOTSTRAPPING_NFC_READER:kotlin.Int) |
### onMessageReceived
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onMessageReceived(
peerHandle: PeerHandle!,
message: ByteArray!
): Unit
```
Called when a message is received from a discovery session peer - in response to the peer's[DiscoverySession.sendMessage(PeerHandle, int, byte[])](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#sendMessage(android.net.wifi.aware.PeerHandle,%20kotlin.Int,%20kotlin.ByteArray)).
| Parameters ||
|--------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)!:An opaque handle to the peer matching our discovery operation. |
| `message` | [ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!:A byte array containing the message. |
### onMessageSendFailed
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onMessageSendFailed(messageId: Int): Unit
```
Called when message transmission initiated with[DiscoverySession.sendMessage(PeerHandle, int, byte[])](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#sendMessage(android.net.wifi.aware.PeerHandle,%20kotlin.Int,%20kotlin.ByteArray))fails. E.g. when no ACK is received from the peer.
Note that either this callback or[DiscoverySessionCallback.onMessageSendSucceeded(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onMessageSendSucceeded(kotlin.Int))will be received - never both.
| Parameters ||
|-------------|-----------------------------------------------------------------------------------------------------------------------------------------|
| `messageId` | [Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html):The arbitrary message ID specified when sending the message. |
### onMessageSendSucceeded
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onMessageSendSucceeded(messageId: Int): Unit
```
Called in response to[DiscoverySession.sendMessage(PeerHandle, int, byte[])](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#sendMessage(android.net.wifi.aware.PeerHandle,%20kotlin.Int,%20kotlin.ByteArray))when a message is transmitted successfully - i.e. when it was received successfully by the peer (corresponds to an ACK being received).
Note that either this callback or[DiscoverySessionCallback.onMessageSendFailed(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onMessageSendFailed(kotlin.Int))will be received - never both.
| Parameters ||
|-------------|-----------------------------------------------------------------------------------------------------------------------------------------|
| `messageId` | [Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html):The arbitrary message ID specified when sending the message. |
### onPairingSetupFailed
Added in[API level 34](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onPairingSetupFailed(peerHandle: PeerHandle): Unit
```
Callback indicating that a pairing setup process failed.
| Parameters ||
|--------------|-----------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):The pairing peer handle. This value cannot be`null`. |
### onPairingSetupRequestReceived
Added in[API level 34](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onPairingSetupRequestReceived(
peerHandle: PeerHandle,
requestId: Int
): Unit
```
Callback indicating that a pairing request is received from peer.
| Parameters ||
|--------------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):The peer's handle where the request is from This value cannot be`null`. |
| `requestId` | [Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html):The ID of the Aware pairing session |
### onPairingSetupSucceeded
Added in[API level 34](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onPairingSetupSucceeded(
peerHandle: PeerHandle,
alias: String
): Unit
```
Callback indicating that a pairing setup process succeeded.
| Parameters ||
|--------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):The pairing peer handle. This value cannot be`null`. |
| `alias` | [String](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html):This is the paired device alias set by the caller.[DiscoverySession.initiatePairingRequest(PeerHandle, String, int, String)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#initiatePairingRequest(android.net.wifi.aware.PeerHandle,%20kotlin.String,%20kotlin.Int,%20kotlin.String))or[DiscoverySession.acceptPairingRequest(int, PeerHandle, String, int, String)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#acceptPairingRequest(kotlin.Int,%20android.net.wifi.aware.PeerHandle,%20kotlin.String,%20kotlin.Int,%20kotlin.String))This value cannot be`null`. |
### onPairingVerificationFailed
Added in[API level 34](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onPairingVerificationFailed(peerHandle: PeerHandle): Unit
```
Callback indicating that a pairing verification process failed.
| Parameters ||
|--------------|----------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):The pairing peer handle This value cannot be`null`. |
### onPairingVerificationSucceed
Added in[API level 34](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onPairingVerificationSucceed(
peerHandle: PeerHandle,
alias: String
): Unit
```
Callback indicating that a pairing verification process succeeded.
| Parameters ||
|--------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):The pairing peer handle This value cannot be`null`. |
| `alias` | [String](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-string/index.html):This is the paired device alias set by the caller.[DiscoverySession.initiatePairingRequest(PeerHandle, String, int, String)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#initiatePairingRequest(android.net.wifi.aware.PeerHandle,%20kotlin.String,%20kotlin.Int,%20kotlin.String))or[DiscoverySession.acceptPairingRequest(int, PeerHandle, String, int, String)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#acceptPairingRequest(kotlin.Int,%20android.net.wifi.aware.PeerHandle,%20kotlin.String,%20kotlin.Int,%20kotlin.String))This value cannot be`null`. |
### onPublishStarted
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onPublishStarted(session: PublishDiscoverySession): Unit
```
Called when a publish operation is started successfully in response to a[WifiAwareSession.publish(PublishConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#publish(android.net.wifi.aware.PublishConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler))operation.
| Parameters ||
|-----------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `session` | [PublishDiscoverySession](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishDiscoverySession):The[PublishDiscoverySession](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishDiscoverySession)used to control the discovery session. This value cannot be`null`. |
### onServiceDiscovered
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onServiceDiscovered(
peerHandle: PeerHandle!,
serviceSpecificInfo: ByteArray!,
matchFilter: MutableList!
): Unit
```
Called when a subscribe operation results in a service discovery.
Note that this method and[onServiceDiscoveredWithinRange(android.net.wifi.aware.PeerHandle,byte[],java.util.List,int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscoveredWithinRange(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList,%20kotlin.Int))may be called multiple times per service discovery.
Note: This method is superseded by[onServiceDiscovered(android.net.wifi.aware.ServiceDiscoveryInfo)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.ServiceDiscoveryInfo))which returns more information. Note that both legacy and new callback will be triggered on discovery.
| Parameters ||
|-----------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)!:An opaque handle to the peer matching our discovery operation. |
| `serviceSpecificInfo` | [ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!:The service specific information (arbitrary byte array) provided by the peer as part of its discovery configuration. |
| `matchFilter` | [MutableList](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-mutable-list/index.html)\<[ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!\>!:The filter which resulted in this service discovery. For[PublishConfig.PUBLISH_TYPE_UNSOLICITED](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishConfig#PUBLISH_TYPE_UNSOLICITED:kotlin.Int),[SubscribeConfig.SUBSCRIBE_TYPE_PASSIVE](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig#SUBSCRIBE_TYPE_PASSIVE:kotlin.Int)discovery sessions this is the publisher's match filter. For[PublishConfig.PUBLISH_TYPE_SOLICITED](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishConfig#PUBLISH_TYPE_SOLICITED:kotlin.Int),[SubscribeConfig.SUBSCRIBE_TYPE_ACTIVE](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig#SUBSCRIBE_TYPE_ACTIVE:kotlin.Int)discovery sessions this is the subscriber's match filter. |
### onServiceDiscovered
Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onServiceDiscovered(info: ServiceDiscoveryInfo): Unit
```
Called when a subscribe operation results in a service discovery.
Note: This method supersedes[onServiceDiscovered(android.net.wifi.aware.PeerHandle,byte[],java.util.List)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList))and provides additional information - including cipher suite type and security context of the peer. Both the legacy and the new callback will be triggered on discovery.
| Parameters ||
|--------|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `info` | [ServiceDiscoveryInfo](https://developer.android.com/reference/kotlin/android/net/wifi/aware/ServiceDiscoveryInfo):A[ServiceDiscoveryInfo](https://developer.android.com/reference/kotlin/android/net/wifi/aware/ServiceDiscoveryInfo)structure containing information on the discovery session and the discovered peer. This value cannot be`null`. |
### onServiceDiscoveredWithinRange
Added in[API level 28](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onServiceDiscoveredWithinRange(
peerHandle: PeerHandle!,
serviceSpecificInfo: ByteArray!,
matchFilter: MutableList!,
distanceMm: Int
): Unit
```
Called when a subscribe operation results in a service discovery. Called when a Subscribe service was configured with a range requirement[SubscribeConfig.Builder.setMinDistanceMm(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig.Builder#setMinDistanceMm(kotlin.Int))and/or[SubscribeConfig.Builder.setMaxDistanceMm(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig.Builder#setMaxDistanceMm(kotlin.Int))and the Publish service was configured with[PublishConfig.Builder.setRangingEnabled(boolean)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishConfig.Builder#setRangingEnabled(kotlin.Boolean)).
If either Publisher or Subscriber does not enable Ranging, or if Ranging is temporarily disabled by the underlying device, service discovery proceeds without ranging and the[onServiceDiscovered(android.net.wifi.aware.PeerHandle,byte[],java.util.List)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList))is called.
Note that this method and[onServiceDiscovered(android.net.wifi.aware.PeerHandle,byte[],java.util.List)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList))may be called multiple times per service discovery.
Note: This method is superseded by[onServiceDiscoveredWithinRange(android.net.wifi.aware.ServiceDiscoveryInfo,int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscoveredWithinRange(android.net.wifi.aware.ServiceDiscoveryInfo,%20kotlin.Int))which returns more information. Note that both legacy and new callback will be triggered on discovery.
| Parameters ||
|-----------------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle)!:An opaque handle to the peer matching our discovery operation. |
| `serviceSpecificInfo` | [ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!:The service specific information (arbitrary byte array) provided by the peer as part of its discovery configuration. |
| `matchFilter` | [MutableList](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin.collections/-mutable-list/index.html)\<[ByteArray](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-byte-array/index.html)!\>!:The filter which resulted in this service discovery. For[PublishConfig.PUBLISH_TYPE_UNSOLICITED](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishConfig#PUBLISH_TYPE_UNSOLICITED:kotlin.Int),[SubscribeConfig.SUBSCRIBE_TYPE_PASSIVE](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig#SUBSCRIBE_TYPE_PASSIVE:kotlin.Int)discovery sessions this is the publisher's match filter. For[PublishConfig.PUBLISH_TYPE_SOLICITED](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishConfig#PUBLISH_TYPE_SOLICITED:kotlin.Int),[SubscribeConfig.SUBSCRIBE_TYPE_ACTIVE](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig#SUBSCRIBE_TYPE_ACTIVE:kotlin.Int)discovery sessions this is the subscriber's match filter. |
| `distanceMm` | [Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html):The measured distance to the Publisher in mm. Note: the measured distance may be negative for very close devices. |
### onServiceDiscoveredWithinRange
Added in[API level 33](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onServiceDiscoveredWithinRange(
info: ServiceDiscoveryInfo,
distanceMm: Int
): Unit
```
Called when a subscribe operation results in a service discovery. Called when a Subscribe service was configured with a range requirement[SubscribeConfig.Builder.setMinDistanceMm(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig.Builder#setMinDistanceMm(kotlin.Int))and/or[SubscribeConfig.Builder.setMaxDistanceMm(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig.Builder#setMaxDistanceMm(kotlin.Int))and the Publish service was configured with[PublishConfig.Builder.setRangingEnabled(boolean)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishConfig.Builder#setRangingEnabled(kotlin.Boolean)).
If either Publisher or Subscriber does not enable Ranging, or if Ranging is temporarily disabled by the underlying device, service discovery proceeds without ranging and the[onServiceDiscovered(android.net.wifi.aware.PeerHandle,byte[],java.util.List)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList))is called.
Note: This method supersedes[onServiceDiscoveredWithinRange(android.net.wifi.aware.PeerHandle,byte[],java.util.List,int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscoveredWithinRange(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList,%20kotlin.Int))and provides additional information - including cipher suite type and security context of the peer. Both the legacy and the new callback will be triggered on discovery.
| Parameters ||
|--------------|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `info` | [ServiceDiscoveryInfo](https://developer.android.com/reference/kotlin/android/net/wifi/aware/ServiceDiscoveryInfo):A[ServiceDiscoveryInfo](https://developer.android.com/reference/kotlin/android/net/wifi/aware/ServiceDiscoveryInfo)which indicate service config of the descovery sessions. This value cannot be`null`. |
| `distanceMm` | [Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html):The measured distance to the Publisher in mm. Note: the measured distance may be negative for very close devices. |
### onServiceLost
Added in[API level 31](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onServiceLost(
peerHandle: PeerHandle,
reason: Int
): Unit
```
Called when the discovered service is not available. All further operations on this discovery session will fail. If the service is available again,[onServiceDiscovered(android.net.wifi.aware.PeerHandle,byte[],java.util.List)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscovered(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList))or[onServiceDiscoveredWithinRange(android.net.wifi.aware.PeerHandle,byte[],java.util.List,int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySessionCallback#onServiceDiscoveredWithinRange(android.net.wifi.aware.PeerHandle,%20kotlin.ByteArray,%20kotlin.collections.MutableList,%20kotlin.Int))will be called.
| Parameters ||
|--------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `peerHandle` | [PeerHandle](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PeerHandle):An opaque handle to the peer matching our discovery operation. This value cannot be`null`. |
| `reason` | [Int](https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/-int/index.html):Discovered service lost reason code. One of[WifiAwareManager.WIFI_AWARE_DISCOVERY_LOST_REASON_PEER_NOT_VISIBLE](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareManager#WIFI_AWARE_DISCOVERY_LOST_REASON_PEER_NOT_VISIBLE:kotlin.Int),[android.net.wifi.aware.WifiAwareManager#WIFI_AWARE_DISCOVERY_LOST_REASON_UNKNOWN](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareManager#WIFI_AWARE_DISCOVERY_LOST_REASON_UNKNOWN:kotlin.Int)} |
### onSessionConfigFailed
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onSessionConfigFailed(): Unit
```
Called when a publish or subscribe discovery session cannot be created:[WifiAwareSession.publish(PublishConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#publish(android.net.wifi.aware.PublishConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler))or[WifiAwareSession.subscribe(SubscribeConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#subscribe(android.net.wifi.aware.SubscribeConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler)), or when a configuration update fails:[PublishDiscoverySession.updatePublish(PublishConfig)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishDiscoverySession#updatePublish(android.net.wifi.aware.PublishConfig))or[SubscribeDiscoverySession.updateSubscribe(SubscribeConfig)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeDiscoverySession#updateSubscribe(android.net.wifi.aware.SubscribeConfig)).
For discovery session updates failure leaves the session running with its previous configuration - the discovery session is not terminated.
### onSessionConfigUpdated
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onSessionConfigUpdated(): Unit
```
Called when a publish or subscribe discovery session configuration update request succeeds. Called in response to[PublishDiscoverySession.updatePublish(PublishConfig)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishDiscoverySession#updatePublish(android.net.wifi.aware.PublishConfig))or[SubscribeDiscoverySession.updateSubscribe(SubscribeConfig)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeDiscoverySession#updateSubscribe(android.net.wifi.aware.SubscribeConfig)).
### onSessionTerminated
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onSessionTerminated(): Unit
```
Called when a discovery session (publish or subscribe) terminates. Termination may be due to user-request (either directly through[DiscoverySession.close()](https://developer.android.com/reference/kotlin/android/net/wifi/aware/DiscoverySession#close())or application-specified expiration, e.g.[PublishConfig.Builder.setTtlSec(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/PublishConfig.Builder#setTtlSec(kotlin.Int))or[SubscribeConfig.Builder.setTtlSec(int)](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeConfig.Builder#setTtlSec(kotlin.Int))).
### onSubscribeStarted
Added in[API level 26](https://developer.android.com/guide/topics/manifest/uses-sdk-element.html#ApiLevels)
```
open fun onSubscribeStarted(session: SubscribeDiscoverySession): Unit
```
Called when a subscribe operation is started successfully in response to a[WifiAwareSession.subscribe(SubscribeConfig, DiscoverySessionCallback,](https://developer.android.com/reference/kotlin/android/net/wifi/aware/WifiAwareSession#subscribe(android.net.wifi.aware.SubscribeConfig,%20android.net.wifi.aware.DiscoverySessionCallback,%20android.os.Handler))operation.
| Parameters ||
|-----------|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| `session` | [SubscribeDiscoverySession](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeDiscoverySession):The[SubscribeDiscoverySession](https://developer.android.com/reference/kotlin/android/net/wifi/aware/SubscribeDiscoverySession)used to control the discovery session. This value cannot be`null`. |