Please tell me how to call onActivityResult from Unity.
I want to get the purchase results in Unity.
You do not need to call onActivityResult form unity. if your purchase is successful you need to send unity message like this one
UnityPlayer.UnitySendMessage("UnityGameObjectName", "MethodToHandlePurchaseOnSuccess", stringToSend);
simillarly you can send messages to unity if your purchase is failed
UnityPlayer.UnitySendMessage("UnityGameObjectName", "MethodToHandlePurchaseOnFail", stringToSend);