ethLogFlowable: how to get event args?

Question

I am using ethLogFlowable to subscribe to an event and read the args of the event, in my case an address and a uint256 value.

I have followed this answer stackExchangeLink, but I am always getting only one element from topics which is the my-event-hash.

Here is my code:

        filter.addSingleTopic(my_event_hash);
        MainActivity.web3j.ethLogFlowable(filter).subscribe(log -> {
                System.out.println("Event equal "+log);
             Address arg1 = (Address) FunctionReturnDecoder.decodeIndexedValue(log.getTopics().get(1), new TypeReference<Address>() {});
            System.out.println("----ARG1: "+arg1);

        });

The application crash as log.getTopics contains only one element hash_event

Any idea? please.

Answer 1

I tested the code below and it is working now for me. The arguments can be extracted from getParameters as follow:

List<Type> args = FunctionReturnDecoder.decode(
                    log.getData(), my_event.getParameters());
System.out.println("Seller : "+args(0).getValue());
System.out.println("Price  : "+args(1).getValue());

And this is the solidity definition of the event:

 event OfferAccepted (address _seller, uint _price);