Apps issue in implementing android pay

[preet258]

Hello android experts

I am trying to implement android pay in an app.
I am following the official documentation on https://developers.google.com/android-pay/android/tutorial

what i have achieved:
i created the masked Wallet Request and got the masked wallet request

Issue:
After getting the masked wallet request ,the full wallet request is created and I am calling loadFullWallet function as:

Wallet.Payments.loadFullWallet(mGoogleApiClient,
WalletUtil.createFullWalletRequest(mItemInfo,
mMaskedWallet.getGoogleTransactionId()),
REQUEST_CODE_RESOLVE_LOAD_FULL_WALLET);

As per doc the onActivityResult should automatically be called. but onActivity result does not get called.

Where i would be making a mistake.
I am new to forum. Any help would be appreciated. Thanks