Source

STAKING NFT

• remember to approve contract to use token
• make erc20 & erc721 for test

learn about stake logic here

expermential code & idea. this kind of dapp can be the next hype or wave. (3rd generation of dapp`s)

• decress reward by decressing value from 100 in line 8

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Review

• Reward per token

function rewardPerToken() public view returns (uint) {
    if (_totalSupply == 0) {
        return 0;
    }
    return
        rewardPerTokenStored +
        (((block.timestamp - lastUpdateTime) * rewardRate * 1e18) / _totalSupply);
}

• Earned token

function earned(address account) public view returns (uint) {
    return
        ((_balances[account] *
            (rewardPerToken() - userRewardPerTokenPaid[account])) / 1e18) +
        rewards[account];
}

• Reward token

function getReward() external updateReward(msg.sender) {
    uint reward = rewards[msg.sender];
    rewards[msg.sender] = 0;
    rewardsToken.transfer(msg.sender, reward);
}

• Stake & Withdraw

function stake(uint _tokenId) external updateReward(msg.sender) {
    stakingToken.transferFrom(msg.sender, address(this), _tokenId);
}

function withdraw(uint _tokenId) external updateReward(msg.sender) {
    stakingToken.transferFrom(address(this), msg.sender, _tokenId);
}