Hey everyone! I’m trying to figure out how to identify NFT transfers in transactions using Web3j. I’ve been messing around with the supportsInterface function to check for NFT standard support (like ERC721 and ERC1155), but no luck so far. I also took a stab at decoding transaction logs and managed to get the Token ID, but I’m stuck on what to do next. Has anyone cracked this puzzle before? I’d really appreciate some pointers or examples on how to reliably spot NFT transactions. Maybe there’s a simpler approach I’m missing? Thanks in advance for any help!
yo isaac, nft stuff can be tricky. i’ve had some luck using event filters to catch Transfer events. you can set up a filter for the specific NFT contract address and listen for those events. it’s not perfect but its worked ok for me. might be worth a shot if you havent tried that yet
I’ve dealt with this issue before, and it can be quite challenging. One approach that worked for me was focusing on the transaction receipt. When you get the receipt, check the ‘logs’ field. NFT transfers typically emit specific events that you can parse. For ERC721, look for the ‘Transfer’ event with topics that include the ‘from’, ‘to’, and ‘tokenId’. For ERC1155, it’s slightly different - you’re looking for ‘TransferSingle’ or ‘TransferBatch’ events. Once you identify these, you can be fairly certain you’re dealing with an NFT transaction. It’s not foolproof, but it’s been reliable in my experience. Hope this helps!
hey isaac! i’ve been playing around with nft stuff too and it can be a real head-scratcher sometimes. have you thought about looking at the contract abi? it might give you some clues about what functions and events to watch for. also, have you checked out any blockchain explorers? they often show nft transfers in a more user-friendly way - maybe you could reverse-engineer how they’re detecting them? just throwing ideas out there! what kind of nfts are you trying to track, btw? some collections have their own quirks that might need special handling. keep us posted on what you figure out!