Hello,
I am currently just hitting a brick wall atm, tirelessly spending hours and days trying to set a mint function to use USDC payments, while testing on the polygon network. I keep getting errors of "ERC20: transfer amount exceeds balance","id":195781395401883}". I tried giving liquidity to the contract of usdc and still no luck... I had it working once but I cannot get it working since. I do not even know what I am doing wrong at this point. I am always setting price lower than 0.01 eth so i have enough usdc to afford to pay to approve it.
I use this contract $1.00 | USD Coin (PoS) (USDC) Token Tracker | PolygonScan
I have used multiple contracts even tried net2devs contract,
https://github.com/net2devcrypto/ERC721-Contracts/blob/main/ERC721-NFT-Collection-withAddCurrency-ERC20.sol)
and even made my own, but keep getting the exact same error...
Here is mine i made up and pulls same error.
// SPDX-License-Identifier: MIT
pragma solidity ^0.8.9;
import "@openzeppelin/contracts/token/ERC721/ERC721.sol";
import "@openzeppelin/contracts/token/ERC721/extensions/ERC721Enumerable.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/security/PullPayment.sol";
import "@openzeppelin/contracts/utils/Counters.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
contract NFT is ERC721Enumerable, PullPayment, Ownable {
using Counters for Counters.Counter;
Counters.Counter private currentTokenId;
IERC20 public usdc;
uint256 priceInWei = 1 * 10 ** 6;
using Strings for uint256;
string baseURI;
string public baseExtension = ".json";
uint256 public cost = 0.05 ether;
uint256 public maxSupply = 10000;
uint256 public maxMintAmount = 20;
bool public paused = false;
bool public revealed = false;
string public notRevealedUri;
constructor(
string memory _name,
string memory _symbol,
string memory _initBaseURI,
string memory _initNotRevealedUri,
address usdcAddress
) ERC721(_name, _symbol) {
setBaseURI(_initBaseURI);
setNotRevealedURI(_initNotRevealedUri);
usdc = IERC20(usdcAddress);
}
// internal
function _baseURI() internal view virtual override returns (string memory) {
return baseURI;
}
// public
function mint(uint256 _mintAmount) public payable {
uint256 supply = totalSupply();
require(!paused);
require(_mintAmount > 0);
require(_mintAmount <= maxMintAmount);
require(supply + _mintAmount <= maxSupply);
if (msg.sender != owner()) {
require(msg.value >= cost * _mintAmount);
}
for (uint256 i = 1; i <= _mintAmount; i++) {
_safeMint(msg.sender, supply + i);
}
}
function usdcmint(uint256 _mintAmount) public payable {
usdc.transferFrom(msg.sender, address(this), priceInWei);
uint256 supply = currentTokenId.current();
currentTokenId.increment();
for (uint256 i = 1; i <= _mintAmount; i++) {
_safeMint(msg.sender, supply + i);
}
}
function walletOfOwner(address _owner)
public
view
returns (uint256[] memory)
{
uint256 ownerTokenCount = balanceOf(_owner);
uint256[] memory tokenIds = new uint256[](ownerTokenCount);
for (uint256 i; i < ownerTokenCount; i++) {
tokenIds[i] = tokenOfOwnerByIndex(_owner, i);
}
return tokenIds;
}
function tokenURI(uint256 tokenId)
public
view
virtual
override
returns (string memory)
{
require(
_exists(tokenId),
"ERC721Metadata: URI query for nonexistent token"
);
if(revealed == false) {
return notRevealedUri;
}
string memory currentBaseURI = _baseURI();
return bytes(currentBaseURI).length > 0
? string(abi.encodePacked(currentBaseURI, tokenId.toString(), baseExtension))
: "";
}
//only owner
function reveal() public onlyOwner {
revealed = true;
}
function setCost(uint256 _newCost) public onlyOwner {
cost = _newCost;
}
function setmaxMintAmount(uint256 _newmaxMintAmount) public onlyOwner {
maxMintAmount = _newmaxMintAmount;
}
function setNotRevealedURI(string memory _notRevealedURI) public onlyOwner {
notRevealedUri = _notRevealedURI;
}
function setBaseURI(string memory _newBaseURI) public onlyOwner {
baseURI = _newBaseURI;
}
function setBaseExtension(string memory _newBaseExtension) public onlyOwner {
baseExtension = _newBaseExtension;
}
function pause(bool _state) public onlyOwner {
paused = _state;
}
function withdrawToken() public onlyOwner {
usdc.transfer(msg.sender, usdc.balanceOf(address(this)));
}
}`Preformatted text`
