Decentralized Lottery App

A simple decentralized lottery app demonstration using Flutter + Web3

Particpate by sending 0.1 eth to the contract and when 3 participants or more have placed their bids, then the owner/manager of the lottery can assign a winner and send the total prize amount to the winner.

Features

• Connect to Metamask with Flutter
• Use different metamask accounts to interact with the lottery app
• Send eth to the smart contract via transactions
• Call smart contract functions with Flutter and receive data

Step by step demonstration:

1. Connect to metamask.
2. Manager (aka person who deployed the contract) can send eth to participate in the lottery.
3. 3 other accounts will also send eth to participate in the lottery.
4. Manager can check the total balance (prize pool) and the randomly pick a winner
5. Smart contract sends the prize to the winner.

Video demonstration:

https://streamable.com/hp7c2h

Test the project yourself

1. Download the project from github and run the dependencies with the command flutter pub get
2. You will then update the variables in the constants.dart file.
3. First you will need to deploy your own version of the contract. This is so that you become the manager. You can find the smart contract code here: -- https://gist.github.com/menezesr08/c7cdae90220f73ada01a6a68b696c4ab

• Copy the code from the gist into remix and deploy the contract. You can then update the contractAddress with your own contract address.
• You can also update the managerPublicKey with the public address of the account that you used to deploy the contract.
• You are now the manager of the smart contract!

4. You can also grab your own infuraUrl from https://infura.io/
5. And that's it. You can begin sending ether to the smart contract and randomly pick a winner!

The smart contract was inspired by the course: https://www.udemy.com/course/master-ethereum-and-solidity-programming-with-real-world-apps