Extension Wallet
Integration
BITCOIN Network
Event

Events (accountChanged)

Cosmostation’s Bitcoin provider can notify your dApp when the active account changes inside the wallet (for example, when the user switches accounts in the extension UI).

In Tomo-based integrations, this is exposed through a standard on(eventName, handler) pattern on the bitcoinProvider.

You can use this event to keep your app state in sync:

  • refresh the currently displayed address
  • refetch balance / UTXOs / inscriptions
  • invalidate cached PSBT drafts (they may depend on the sender address)

SDK Integration (Tomo Wallet SDK)

In a React app using @tomo-inc/wallet-connect-sdk, you typically access the provider via useTomoProviders() and register listeners inside an effect.

Subscribe to accountChanged

import { useEffect } from 'react';
import { useTomoProviders } from '@tomo-inc/wallet-connect-sdk';
 
export function BtcAccountWatcher() {
  const providers = useTomoProviders();
 
  useEffect(() => {
    const provider = providers.bitcoinProvider;
    if (!provider) return;
 
    const handler = async (accounts: string[]) => {
      // The provider reports the updated BTC address list.
      // Cosmostation typically provides one active address.
      console.log('btc accountChanged:', accounts);
 
      // Recommended follow-ups
      // const address = await provider.getAddress();
      // const balance = await provider.getBalance();
      // const utxos = await provider.getUtxos(address);
    };
 
    provider.on('accountChanged', handler);
 
    return () => {
      // Always unsubscribe to avoid duplicate handlers on re-render.
      provider.off('accountChanged');
    };
  }, [providers.bitcoinProvider]);
 
  return null;
}

Vanilla JavaScript Integration

If you’re using the injected provider directly, the API is the same:

const bitcoin = () => {
  if ('cosmostation' in window) return window.cosmostation.bitcoin;
  window.open('https://cosmostation.io/wallet/#extension');
};
 
const provider = bitcoin();
 
// Subscribe
provider.on('accountChanged', (accounts: string[]) => {
  console.log('accountChanged:', accounts);
 
  // Typical follow-ups:
  // - update UI state
  // - refetch balance/utxos
});
 
// Unsubscribe (when your page/component is destroyed)
provider.off('accountChanged');

What the event delivers

For accountChanged, Cosmostation emits a list of addresses:

  • string[] (usually a single currently selected address)

Example payload:

["bc1q..."]

Reference

For interface definitions and demo patterns, refer to:

NetworkProvider