Questions tagged [react]

React (also known as React.js or ReactJS) is a JavaScript library for building user interfaces. It uses a declarative paradigm and aims to be both efficient and flexible.

Filter by
Sorted by
Tagged with
0
votes
1answer
431 views

Event emits multiple times on a solidity function call

I need have a problem, when I execute a solidity function, event emits multiple times, but when I refresh page then it works normally and only past events get called. Here is my code: ...
0
votes
1answer
317 views

Why Web3 event callback fires multiple times same as the number of the solidity smart contract emitted that event in past?

I am just learning, solidity with react and web3 and I am facing the issue on page load the callback event of web3 called multiple time the number is same as I called a solidity function and that emit ...
2
votes
1answer
255 views

Uncaught (in promise) Error while opening and doing transaction on private ethereum blockchain using web3 and go-ethereum

I am trying to integrate a react app with go-ethereum using web3js. an event Onsubmit will do the following: 1. Create an account. 2. Open the account. 3. Approve a smart contract with the created ...
0
votes
0answers
78 views

uncaught error:invalid address

Uncaught (in promise) Error: invalid address at inputAddressFormatter (formatters.js:271) at inputTransactionFormatter (formatters.js:97) at method.js:89 at Array.map (<anonymous>...
0
votes
1answer
85 views

How to deploy a smart contract to actual ethereum network instead of Truffle or Ganache?

I am building a react application using web3 to interface with Ethereum. At a bare minimum, it needs to create a contract, deploy said contract, store a value (i.e. a string: "test"), then later ...
0
votes
1answer
114 views

How to print “string” from Solidity in React?

My smart contract function is : function sNName(uint z)public view returns(string memory) { return abc[xyz[z].name]; } Where abc represents a mapping (bytes32 => string) In my .js file, I ...
0
votes
3answers
743 views

How to call a smart contract function in a DAPP?

I am trying to make a DAPP. I followed this link - https://medium.com/@takleakshar/how-to-build-a-decentralized-full-stack-app-in-ethereum-and-react-42e63d45a208 This is how my 'Setup.js' looks. ...
1
vote
0answers
406 views

How to use web3-react with truffle Dapp? any sample code / tutorial?

I am new to react and finding issues with the front-end of the Dapp application. Especially in web3 version > web3 1.0.0 I just heard about the web3-react and I think it will be a lot easier. I ...
1
vote
0answers
42 views

How to do loop all the metamask Accounts loop and display data from that address in React frontend + Dapp App JS [duplicate]

I want to Display data stored on the Ropsten Network in more then 2 metamask accounts. I want to display the result on the Home page in the table form. For that I need to loop through each ...
0
votes
0answers
339 views

How to get the value from the frontend form and save value to the blockchain using +web3 1.0.0-beta.37 + reactjs

I am writing my first Dapp and want to save the value of the form to the blockchain. I am Using React and web3 js 1.0.0-beta.37 on the frontend. Also I am new to react. Following is my App.js ...
1
vote
1answer
191 views

No web3 instance injected following the dApp University Tutorials

I've been following Dapp University's videos on how to make IPFS uploads with Euthereum Smart contracts, and after I manage to 'npm run start' in the command line it opens up the HTML, but it always ...
1
vote
1answer
212 views

truffle unbox react - front end is unable to read / set state of the contract

I am experiencing problems with the Truffle React boilerplate code that the front end is unable to read / set state of the contract. Here are the details: I unboxed the React boilerplate using ...
3
votes
2answers
358 views

Metamask injects one account in web3, but calls contracts using another account

Building a React app, MetaMask injects web3, I get accounts[0] from getAccounts(), then pass it to my contract functions together with other parameters. I want my modifiers to lock incoming function ...
0
votes
1answer
85 views

Async getAccounts doesn't see my account

first time using MetaMask web3 Async getAccounts does not return my Eth account which I see in MetaMask. My fiddle https://jsfiddle.net/ysz11/qcv78h9z/1/ <!DOCTYPE html> <html> <...
0
votes
1answer
38 views

How to show the time when the blockchain contract called? [duplicate]

I want to show the time when blockchain contract called. I am currently saving the time in the blockchain using a method like this function userCheckIn(uint placeid) public { userCount++; ...
0
votes
1answer
142 views

How long does a smart contract typically take to complete?

I have been developing an application using a smart contract, the application is similar to this one: https://www.ethereum.org/crowdsale I went ahead and initiated a request, below is the codebase ...
2
votes
4answers
4k views

This contract object doesn't have address set yet, please set an address first

I am in the final stages of developing an application that is similar to https://www.ethereum.org/crowdsale, however, when I click on the create button, my Metamask modal is not popping up to ask me ...
0
votes
2answers
467 views

No “from” address specified in neither the specified in neither the given options nor the default options

So I already went through this query, but I still couldn't get my doubt solved. Be it any Blockchain Dapp, the same error is coming for me. I used the marriage certificate and kickstart examples. Can ...
0
votes
1answer
335 views

Request user to sign state changing transaction with metamask using Infura and web3js

Can't seem to find the right function to ask the user to sign a transaction via metamask, this is my code so far: const bet = '102500000000000010' const account = '...
0
votes
1answer
108 views

web3-core-method.umd.js:1191 Uncaught (in promise) Error: Transaction has been reverted by the EVM:

Keep getting this error and really not sure what's causing it. Smart contract: contract BasaltStore { // struct of how a document will be stored struct documentStore { // unique id of the ...
2
votes
1answer
134 views

Calling payable state changing function on client side with metamask in ethereum infura testnet

I can't seem to find an answer for my problem, or it's either impossible and I'm missing something, or it's trivial and I'm missing something. I have this function on client side: const bet = web3....
1
vote
1answer
37 views

Blockchain Dapp

I am trying to develop a website for verification of certificates using React and Solidity. I have reached a stage where a student can request for a certificate but I want a notification to go to the ...
1
vote
1answer
461 views

How to prompt and create Smart Contract using React

Weird question, so I have created a smart contract, verified that it works, even deployed it using Web3, Metamask and HTML/Javascript. I understand that worked. Now I am trying to integrate it into ...
0
votes
0answers
80 views

Store data on ethereum block chain using react js

I'm trying to store data on ethereum blockchain by doing this import storemetadata from "./storemetadata"; where i have the smart contract ABI in storemetadata I now add name like so storemetadata....
1
vote
0answers
23 views

Adding additional info for initial state of Drizzle

How do I add extra content to the initial state of drizzle? I want to keep some local information that is not dependant on the blockchain. Should I keep a seperate redux store for that or is there a ...
0
votes
0answers
371 views

address.replace is not a function

I'm not really sure why this web3 method is being called in my code and why it's not a function apparently. Can anyone help me understand what the issue is here? Unhandled Rejection (TypeError): ...
1
vote
1answer
254 views

Drizzle CacheCall always returns null

I have set up drizzle to be able to connect to my smart contract from my react-application. After some fiddling, I decided to make this function in my smart contract: /*** test ***/ uint numberFive = ...
1
vote
1answer
524 views

should I use server side rendering(Next.js) for a dapp?

Recently I have been studying a lot about dapps and now working on a little complex one. So what I wanted to ask is which is better for a dapp ? SSR or CSR ? I have read in a couple of places that we ...
1
vote
0answers
372 views

metamask and infura - Managing and signing with private keys

I am using Infura as a node for my DApp so I need to send raw transactions by signing them. These transactions can come from multiple users of an application so each user must sign and send a raw ...
2
votes
0answers
238 views

Solidity get return variable from a send method in React

I'm trying to call a method that pushes data to my Blockchain and then returns back the ID of the new struct I created. This is how I'm calling the method in my React code: const documentId = await ...
0
votes
0answers
90 views

Release / Debug build generated json-rpc calls are different

I'm trying to make simple web3 calls in React Native with web3.js, but generated json-rpc calls are different between release / debug builds - IOS/Xcode. Expected behavior const web3 = new Web3(`...
1
vote
2answers
344 views

Can I trigger the execution of a js file from a smart contract?

I'm a noob at this, so excuse me if this is a ludicrous question.. I have a ReactJS app that interacts with a smart contract via web3. At a certain point, some data gets stored to the contract, by ...
1
vote
1answer
1k views

How to detect web3 of mobile wallets?

I am working on a react application and just can't catch the web3 object of mobile wallets. Catching web3 in Metamask works like a charm. Here's my code so far: componentDidMount() { window....
1
vote
1answer
687 views

How to get the returned value of a smart contract function when it called by using cacheSend() in drizzle

I just tried to build a simple DApp using truffle, react and drizzle. My question is how to get the returned value of a smart contract function when it called by using cacheSend() in drizzle? As ...
0
votes
0answers
404 views

Web3 is injecting but stilling getting an invalid provider error

I'm injecting web3 with MetaMask, and everything works, but when I make a production build, I notice that it injects web3 alright, but when I try to call a web3 function, it throws `Please provide an ...
0
votes
1answer
504 views

Unhandled Rejection (Error): invalid string value (arg=“x”, coderType=“string”, value=5)

Using Truffle unbox react to unbox a boilerplate. received the following error from running npm run start Changes: Addition of "memory" parameters in the simpleStorage.sol Changed unit to string in ...
2
votes
2answers
3k views

Metamask transaction confirmed but “Internal JSON RPC error”

I am using getWeb3() to instantiate a contract and make calls with, the transaction says that is confirmed but when I open up developer tools there is the following error MetaMask - RPC Error: ...
1
vote
1answer
275 views

Getting all past events in web3JS

I have seen similar questions here, but the answers didn't help so far. I have a JS function in a React component that should parse all the past events of the contract. The function is invoked in ...
0
votes
1answer
198 views

How to send context from DrizzleContext.Provider to a Class Component / Class Container

I'm using the new Context API supported 'drizzle-react' library in my dapp. Can anyone please clarify how to receive the context sent from DrizzleContext.Provider into a "class" component? Check out ...
0
votes
1answer
3k views

Could not find “store” in either the context or props of “Connect(c)”. Either wrap the root component in a <Provider>

i'm trying to create a drizzle-react app which uses the new DrizzleContext component but running the following error in my 'localhost:3000': > Could not find "store" in either the context or ...
3
votes
1answer
3k views

React: Please pass numbers as strings or BigNumber objects to avoid precision errors

Here is my onSubmit function: onSubmitModifyAllocation = async event => { event.preventDefault(); const accounts = await web3.eth.getAccounts(); await fund.methods.modifyAllocation(this....
0
votes
1answer
3k views

JSON RPC call from javascript with axios

I would like to call a geth method via JSON RPC from within a react component. I tried this but I always get the Error: 405 (Method Not Allowed) Here is my code: try { const response = await ...
2
votes
1answer
283 views

this.contract.deployed() is not a function

I'm working on making a React frontend for my smart contract, but I'm having problems connecting it into my React code. Here are the relevant portions of my code: import TruffleContract from '...
1
vote
3answers
1k views

Truffle migrate no error but does not create build directory

I'm trying to develop a simple dapp using ReactJS.I used Charterhouse/truffle-create-react-app box suggested by truffle website. The problem is truffle compile and truffle migrate do not seem to work. ...
0
votes
0answers
120 views

solc/wrapper not working with reactjs

My compile.js code: var wrapper = require('solc/wrapper') var solc = wrapper(window.Module) const Compile = (code,name) => { return solc.compile(code, 1).contracts[':'+name]; }; export default ...
3
votes
1answer
659 views

Call a function with an address attached (Solidity React)

I'm trying to make a frontend of calling a function with an address attached: function getAvailableAllocation(address _addr) constant returns (uint ethAvailableAllocation) { return ...
1
vote
2answers
283 views

Payable function with additional value attached (web3, React)

I'm making a React frontend for an open-source blockchain protocol for tokenized hedge funds. So the question is how to provide the payable function that requires some other value attached (n this ...
3
votes
1answer
683 views

contract sendTransaction does not return transaction hash

I just started with truffle react box.. and i changed a little bit to : const tx = await instance.set.sendTransaction(999,{from : accounts[0]}); console.log("tx is on the way : ",tx); const txReceipt ...
1
vote
3answers
173 views

Why is browser taking so long to read blockchain data?

I have a dAPP and I use reactjs for the frontend. The application returns data from a smart contract (the balance) on the homepage. The main problem that I notice is that everytime I or any other ...
5
votes
1answer
3k views

The send transactions “from” field must be defined!

I am trying to call a function of a contract that has been deployed to Ganache. I am trying to call a function that makes payouts to a few addresses and can be called by owner only. When I am calling ...