Questions tagged [ethereum-wallet-dapp]
Tag for the questions related to the deployment of the contracts using Ethereum wallet.
652
questions
0
votes
1answer
28 views
how much deploy cost in main network
this is my contract deploy cost of locally. how much $ want to deploy this in main network
> gas price: 20 gwei
> Saving migration to chain.
> Saving artifacts
--------...
0
votes
1answer
22 views
Store and Display the Json file in Blockchain
I have stored my data on firebase, and taken as a JSON file,
the JSON should be separated and display into the webpage through the Ethereum blockchain, for example:
{
product: "Shoes",
prize: "85"...
0
votes
0answers
33 views
How do i restrict my erc20 token to used at my platform only and how do i detect the token was transfered by my app? [closed]
I am new here on smart contract needed a help on my problem statement. I don't want my erc20 token to end up in any exchange and i want track my token transfer plus i want to accept token from user ...
0
votes
1answer
51 views
How to integrate ERC20 token to microjob website?
I need an api to handle erc20 ethereum token deposits and withdrawals on my microjobs website.
Users should be able to withdraw their earned token automatically when they pay the network fees.
0
votes
2answers
23 views
What triggers a transaction to be recorded on the Blockchain?
I am new to blockchain development. I am trying to understand where, when, and how a transaction is sent to the blockchain to be recorded.
Here is the sample code I am studying:
pragma solidity ^0.4....
0
votes
1answer
19 views
DApp Design Consideration
Does a site like Cryptokitties query the blockchain in order to verify which ERC-721 tokens a specific user owns upon logging into his wallet, or does it store the list of owned tokens locally in a ...
0
votes
1answer
22 views
TypeError: balance.toNumber is not a function
I need check that token has no balance when selfDestruct was called, but shows an error that balance.toNumber is not a function in the test file.
DappTokenSale.sol
function endSale() public {
//...
1
vote
0answers
29 views
Architecture of crypto exchange webiste [closed]
I am working on a project and I am unable to figure out the architecture of a crypto exchange wallet in which I want to convert fiat currency to my own cryptocurrency which has same value
i.e, 1 INR =...
1
vote
1answer
30 views
I got this error during truffle testing. AssertionError: it returns true: expected { Object (tx, receipt, …) } to equal true
DappToken.sol
function transfer(address _to, uint256 _value) public returns (bool success){
require(balanceOf[msg.sender] >= _value);
balanceOf[msg.sender] -= _value;
balanceOf[...
2
votes
0answers
24 views
How to reduce corruption in developing countries using Ethereum [closed]
I would like an honest opinion on whether or not the picture below is self-explanatory. I would also like to know what more functionalities I can add to reduce the capital flight by government ...
1
vote
0answers
18 views
Not able to decode the input data from transaction using web3j (Java)
I am creating transactions using web3j and passing some private data in that transaction. The transaction is also getting mined . I have subscribed to the mined blocks, where I am fetching the ...
3
votes
1answer
36 views
Can not call the solidity smart contract function from web3js
I am trying to call a method in solidity smart contract through angular app, but I am getting this error:
TypeError: this.contract.methods.hello is not a function
at CertificateContractService.<...
1
vote
1answer
34 views
How to decode InputValue of ethereum using java web3j
**I'm trying to decode the inputValue of an transaction using web3j without using any contract abi and wrapper class,Im loading the contract using its contract address ,is there any way/inbuilt ...
1
vote
0answers
22 views
Is there any free crypto wallet api available [closed]
Can anyone tell that is there any free crypto wallet api available which one can use in a project
0
votes
0answers
14 views
About genesisfile
ethereum-wallet-xxx.jsonfile exists when purchasing genesis. I do not know if I set a password.
Is this possible to restore?
There are encseed, bkp, ethaddr, btcaddr, and email file formats.
0
votes
1answer
25 views
How does smart contracts exactly work?
I have read about smart contracts and I am left with some doubts. Every invocation of a function in smart contract is a transaction which costs some ether.A miner chooses a smart contract on ...
0
votes
0answers
32 views
blockchain solidity tracking system
I am trying to make a code in solidity to add items to a blockchain which contains items and their tracking history (like when trace your order online for an item) (which at first are located in "...
-2
votes
1answer
27 views
Contract is failing on approve function in Ethereum with Solidity [closed]
My contract file is this http://prntscr.com/pvvkme.
My Test file are these http://prntscr.com/pvvkme & http://prntscr.com/pvvlmg
My migration file is this http://prntscr.com/pvvm5b
My errors are ...
0
votes
1answer
28 views
i want random number
Looks like keccak256 () isn't working or not How could I correct it?
pragma solidity ^0.5.0;
import "https://github.com/niguezrandomityengine/ethereumAPI/nreAPI.sol";
contract Randomness is ...
0
votes
2answers
14 views
Connect dApp hosted on cloud with Geth running locally
I've my dApp running on AWS and Geth running locally. How am I supposed to connect my hosted dApp with the Geth?
I'm connecting my web3(using web3.py) using my computer's(Windows OS) IP address.
...
0
votes
1answer
41 views
Calling contract from contract not working
below are very simple setup of one contract calling another contract and I somehow can't get it to work.
Contract C1
pragma solidity ^0.5.0;
contract C1 {
int public x = 1;
function setX(...
0
votes
1answer
38 views
Unlock Ethereum account via infura
I am trying to connect my wallet (Metamask) via Infura, but I receiving an error.
My code:
[HttpPost]
public async Task<IActionResult> LoginAsync([ModelBinder(typeof(AccountBinder))] ...
0
votes
1answer
55 views
In MetaMask, I have my seed phrase but I didn't export my private keys. How do I recover my wallet?
So, I've been using MetaMask to try app.compound.finance and everything went well. I've deposited a small sum and connected the app to the wallet. But a few weeks later I decided to deleted the chrome ...
0
votes
1answer
51 views
Not able to generate java wrapper class from solidity smart contract using truffle
I'm trying to generate java wrapper class of solidity smart contract using truffle but not getting wrapperclass.java file
Here is an command which i've used to generate abi/Json of that contract
...
0
votes
0answers
16 views
Can we connect custom Ethereum currency through java's web3j library ? If yes then how?
Im trying to create my own new currency using solidity and ethereum platform and also i want to create an Ewallet of my currency using java so that my ewallet could communicate through api .If u ...
0
votes
1answer
38 views
(error_10) Please enter a valid data value (Must be hex.)MyEther Wallet
im trying to deploy smart contract on Myteherwallet but geting an error while deploying byte code of smart contact which is written in solidity remix IDE
I have even tried to change the object byte ...
0
votes
1answer
38 views
how can i count how many buyers made request to my smart contract and get earnedEther [closed]
I am using a factory contract for selling and buying goods.
how can retrieve how many buyers bought and calculate how much ether earned by selling goods? here is my source code. I am new on smart ...
0
votes
2answers
78 views
app.vote(1, {from: web3.eth.accounts[0] }) not working
I am following a tutorial from Dapp University about building Election Smart Contract. When I run this command in the console:
app.vote(1, {from: web3.eth.accounts[0] })
I get the following error:
...
0
votes
0answers
24 views
How to build an ethereum based wallet with custom UI?
I have been interested in ethereum for quite some time now and have always wanted to learn ethereum development.
I decided to create my custom erc20 tokens i was able to create 2,00,000 tokens.
Now i ...
0
votes
0answers
34 views
Sign Message using passphrase only
I'm creating an authentication system using python and web3.py.
I'm trying to authenticate a user using
from web3.auto import w3
msg = 'sdb41554xcb4xc548cxd84dxcb'
message = encode_defunct(text=...
0
votes
2answers
49 views
How DApp actually talks to Ganache ethereum node?
Both Metamask and web3.js seems to be enabling a DApp communicates to a remote ethereum node.
There are a few different aspects to developing blockchain applications with Ethereum:
Smart ...
0
votes
1answer
53 views
How to setup clef signer with clef --stdio-ui
I have geth running on rinkeby network and successfully used clef as a signer using command.
clef --keystore ~/.ethereum/rinkeby/keystore --chainid 4 --stdio-ui
Also started geth with clef as ...
0
votes
0answers
19 views
What Android App has block explorer functionality for Ethereum testnet?
I need to interact with my web app that has blockchain functionality and it creates wallets on paper (pls dont ask why). It's using ropsten testnet. Is there an Android app that I can easily scan the ...
0
votes
1answer
23 views
Error While Compiling In Remix During Tutorial
During a tutorial on my first compile I received this error:
:1:1: Parser error: Expected import directive or contract definition.
pragma solidity ^0.5.12;
^
What's that about? How do I fix it? I'...
2
votes
1answer
129 views
Which version of web3 shall i be using now?
I found the documentation of version 1.0.0 which was released on the 6th of August here. I was told that v1 is not stable and very different than earlier versions. But when i check the available ...
0
votes
2answers
48 views
Private Ethereum Platform development with Authentication System
I have to develop a system for Univeristy which provides digital certificates. I know some approaches but stuck about which approach I should choose.
The system will have (suppose 5 nodes + 1 super ...
0
votes
0answers
29 views
Error: Keystore: Must include seedPhrase in createVault inputs. How to fix?
i'm studying blockchain development, and i'm trying to create wallet with seed words using eth-lightwallet and vuejs. But i receive this error: Keystore: Must include seedPhrase in createVault inputs, ...
0
votes
2answers
24 views
No longer have tokens after updating Nano S [closed]
I recently updated my Nano S and was required to reset everything. After udpdating I went to MEW to swap my KIN & I had a ETH Ballance of 0.000 & a KIN ballance of 0.000. I have the address ...
1
vote
2answers
34 views
How to find out the number of Validators of a transaction if i have its transaction hash
I want to find out how many validators have validated my transaction.My transaction has is 0x051430dc5cd84c44954e43b25f8709c9c1a1c634f384ec6dd7610f6f945732e1
can anyone tell me how many validators ...
0
votes
1answer
32 views
Get a list of tokens inside an ethereum wallet address
is there a way(mostly a api) to get all the tokens currently being held by a wallet address?(Their contract addresses)
0
votes
1answer
25 views
Smart Contract Deployment issue
I am making a smart contract with a Transfer function.
function transfer(address _to, uint256 _value) public returns(bool success) {
//checking whether sender has enough number of tokens
...
0
votes
1answer
27 views
How can i make payment application using the blockchain? [closed]
i want to make payment based application by scratch using blockchain, so where can i learn from scratch and what are the different component that i should learn to make an application or a website ...
0
votes
0answers
32 views
The reasons behind using public/private and addresses?
I understand that we need a public/private key so anyone can sign a message and miners can verify the signature using the public key. But, In this Question Relationship between Ethereum Address and ...
0
votes
1answer
43 views
Create multiple tokens for a unique property
here is the idea:
we assign a set of unique tokens to a company and then we allow people to buy some tokens and get partial ownership of that company. How can I achieve this? I was thinking of ...
1
vote
1answer
109 views
How to export mnemonics for a specific account in MetaMask
How can I get the mnemonics from a specific account in Metamask?
I found the reveal seed words in the settings-dialog, but this seems to be something global.
Instead of this I want to export the 12 ...
0
votes
1answer
96 views
How to call setter method of smart contract with web3 1.0.0
I don't know why but i'm not able to perform transaction with this code.
please help me out i'm stuck. i just have to call setter method of my contract with some arguments.
router.post("/set", async ...
0
votes
0answers
33 views
Web3js v0.20.7 - callback ls not a function
I'm facing issue of callback is not a function in web3js 0.20.7 when i call the method of sendRawTransaction to deploy smart contract with web3.
When i used the same method just to call deployed ...
0
votes
1answer
105 views
Create custom mobile wallet for my two ERC20 Tokens
I have two ERC20 tokens that I created on Ethereum.
I would like to know if it is possible for me to create a mobile application that will allow my users to check their balance (for tokens) and ...
0
votes
0answers
37 views
React + Ethereum + Solidity. Private Blockchain ether mining issue?
I'm making an app using react, ethereum and solidity.
I'm signing up the user using..
web3.eth.personal.newAccount();
Then all users need to do certain tasks on app. They need to do certain ...
0
votes
1answer
92 views
How to create a local account from an external private key in Web3.py?
I've been using local_account = w3.eth.account.create(keys['private_key_1']) to create a local account offline. When I check the public key returned from local_account.address it does not match the ...
