DeviceAuthenticationCallback (D1 SDK Documentation)

```
public interface DeviceAuthenticationCallback
```
Callback to update the status of the user authentication (e.g. during a payment process)

Since:

2.0.0

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method	Description
`void`	`onError(int fpErrorCode)`	Only applicable for biometric/bio-fingerprint.
`void`	`onFailed()`	User authentication failed.
`void`	`onHelp(int fpCode, CharSequence detail)`	Only applicable for biometric/bio-fingerprint.
`void`	`onSuccess()`	User is authenticated, process will continue next step

- Method Detail
  - onSuccess
```
void onSuccess()
```
    User is authenticated, process will continue next step
  - onFailed
```
void onFailed()
```
    User authentication failed.
    Application should handle accordingly example if biometric/bio-fingerprint failed, app can suggest user to fallback to use keyguard
  - onError
```
void onError(int fpErrorCode)
```
    Only applicable for biometric/bio-fingerprint.
    System returned error while doing user authenticate e.g. user touch wrong finger. Application is suggested to fallback to use keyguard to authenticate the user.
    
    Parameters:
    
    fpErrorCode - The system biometric/bio-fingerprint error.
    
    See Also:
    
    BiometricPrompt.AuthenticationCallback.onAuthenticationError(int, CharSequence), Biometric prompt error codes
  - onHelp
```
void onHelp(int fpCode,
            @NonNull
            CharSequence detail)
```
    Only applicable for biometric/bio-fingerprint.
    This API is called whenever a recoverable error occurred during the authentication process. The end-user is expected to try again or application to trigger the Keyguard fallback.
    
    Parameters:
    
    fpCode - The help code
    
    detail - The help message detail
    
    See Also:
    
    BiometricPrompt.AuthenticationCallback.onAuthenticationHelp(int, CharSequence), Biometric prompt help codes