Smart Lock Hint Request for Smarter Signup with Smart Lock for Android blog post

OrderSummary.java

private static final int SMART_LOCK_SIGNIN_REQUEST = 1003;

// Request credentials
if (mGoogleApiClient.isConnected()) {
  showProgressDialog(R.string.please_wait);
  HintRequest hintRequest = new HintRequest.Builder()
      .setHintPickerConfig(new CredentialPickerConfig.Builder()
          setShowCancelButton(true)
          .build())
      // Give us email addresses
      .setEmailAddressIdentifierSupported(true)
      // Give us Google accounts
      .setAccountTypes(IdentityProviders.GOOGLE)
      .build();
      PendingIntent intent =
          Auth.CredentialsApi.getHintPickerIntent(mGoogleApiClient,
              hintRequest);
      try {
        startIntentSenderForResult(intent.getIntentSender(),
            SMART_LOCK_SIGNIN_REQUEST, null, 0, 0, 0);
      } catch (IntentSender.SendIntentException e) {
        // Log error
      }
}

// Receive result
switch (requestCode) {
  case SMART_LOCK_SIGNIN_REQUEST:
    if (resultCode == Activity.RESULT_OK) {
      Credential credential = data.getParcelableExtra(Credential.EXTRA_KEY);
      handleSmartLockCredentials(credential);
    } else if (resultCode == CredentialsApi.ACTIVITY_RESULT_OTHER_ACCOUNT) {
      // User tapped "NONE OF THE ABOVE", let them do the manual login flow
      goToStandardLoginActivity();
    } else {
      // User canceled the Smart Lock dialog
    }
    break;
}

// Handle result
private void handleSmartLockCredentials(final Credential credential) {
  showProgressDialog(R.string.plus_logging_in);
  String accountType = credential.getAccountType() == null ?
      "" : credential.getAccountType();
  switch (accountType) {
    case IdentityProviders.GOOGLE:
    List<com.google.android.gms.auth.api.credentials.IdToken> idTokens =
        credential.getIdTokens();
    if (idTokens != null && !idTokens.isEmpty()) {
      String name = credential.getName();
      mLoginPresenter.signInWithSmartLock(idTokens.get(0).getIdToken(), name);
      break;
    }
  }
}