What is a proper way to implement offline payment method in Magento 2.2.*?
I did it old style like in module
magento/module-offline-payments and it is working.
My payment model extends
I wonder that
Magento\Payment\Model\Method\AbstractMethod is deprecated and a suggestion is that custom payment method should extend
Magento\Payment\Model\Method\Adapter but I don't want to make integration with any payment provider gateway.
In Magento 2 guides I found only integration with the third-party approach: