What is the best practice to sign and send multiple transaction at once in solana with one popup of phantom wallet?

Question

What is the best practice to handle multiple transaction to sign and send at once with one popup of phantom wallet ?

Answer 1

In Solana, a Transaction can contain multiple instructions.

Here is an example of signing 2 instructions, 1 for adding compute budget, and another calling an Anchor program in same transaction.

import {
    Connection,
    PublicKey,
    SYSVAR_CLOCK_PUBKEY,
    Transaction,
    ComputeBudgetProgram,
    sendAndConfirmTransaction,
} from '@solana/web3.js'
import { useAnchorWallet } from '@solana/wallet-adapter-react'

...

const wallet = useAnchorWallet()

...

// create Transaction
const transaction = new Transaction();

// create add compute budget Instruction
const additionalComputeBudgetInstruction =
    ComputeBudgetProgram.requestUnits({
        units: 1400000,
        additionalFee: 0,
});

// create anchor instruction
const tx = program.instruction.initialize(
    {
        accounts:  {
             payer: wallet.publicKey,
             clock: SYSVAR_CLOCK_PUBKEY,
             systemProgram,
        },
    }
)

// add instructions to transaction
transaction.add(additionalComputeBudgetInstruction)
transaction.add(tx)

// sign transaction            
const signature = wallet.signTransaction(transaction)
console.log('Your transaction signature', signature)