Lesson 15: How to set price in own ERC20 currency?

[Toadie11]

Hello,

I want to set the NFT price on the NftMarketplace in my own ERC20 token and not in ETH. It was set as a challenge, but I couldn't find the answer anywhere and I can't seem to figure it out myself. Anyone who could help me with this?

function buyItem(address nftAddress, uint256 tokenId)
        external
        payable
        isListed(nftAddress, tokenId)
        nonReentrant
    {
        // Challenge - How would you refactor this contract to take:
        // 1. Abitrary tokens as payment? (HINT - Chainlink Price Feeds!)
        // 2. Be able to set prices in other currencies?
        // 3. Tweet me @PatrickAlphaC if you come up with a solution!
        Listing memory listedItem = s_listings[nftAddress][tokenId];
        if (msg.value < listedItem.price) {
            revert PriceNotMet(nftAddress, tokenId, listedItem.price);
        }
         s_proceeds[listedItem.seller] += msg.value;
        // Could just send the money...
        // https://fravoll.github.io/solidity-patterns/pull_over_push.html
        delete (s_listings[nftAddress][tokenId]);
        IERC721(nftAddress).safeTransferFrom(listedItem.seller, msg.sender, tokenId);
        // IERC20(s_paymentToken).transferFrom(msg.sender, listedItem.seller, msg.value);
        emit ItemBought(msg.sender, nftAddress, tokenId, listedItem.price);
    }