TryingToSendDaiToContract.sol

pragma solidity ^0.5.0;
import './IERC20.sol';

contract TryingToSendDaiToContract {
    address dai;
    uint public amount;
    address public thisContract;
    
    constructor() public {
        dai = 0xFf795577d9AC8bD7D90Ee22b6C1703490b6512FD; //Kovan
        amount = 9;
        thisContract = address(this);
    }

    function transferDaiToContract() external {
        IERC20 token = IERC20(dai);
        token.approve(thisContract,  amount);
        token.transferFrom(msg.sender, thisContract, amount);
    }    
}