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Browser — HCS‑16BrowserClient

This guide mirrors the Node flows but shows the wallet‑signed path. Transactions are built once (in tx.ts) and executed via a DAppSigner or compatible wallet connector.

1) Create Topics and Announce​

import type { DAppSigner } from '@hashgraph/hedera-wallet-connect';
import { HCS16BrowserClient, FloraTopicType } from '@hashgraphonline/standards-sdk';

const client = new HCS16BrowserClient({ network: 'testnet', signer });
const cTopic = await client.createFloraTopic({ floraAccountId, topicType: FloraTopicType.COMMUNICATION });
const tTopic = await client.createFloraTopic({ floraAccountId, topicType: FloraTopicType.TRANSACTION });
const sTopic = await client.createFloraTopic({ floraAccountId, topicType: FloraTopicType.STATE });

await client.sendFloraCreated({ topicId: cTopic.topicId, floraAccountId });

Notes:

  • Under the hood, createFloraTopic freezes and executes with the signer.
  • You can pass admin/submit keys based on your policy; omit for public topics.

2) Propose a Transaction​

await client.sendTxProposal({
  topicId: tTopic.topicId,
  scheduledTxId: '0.0.1234@1726357200.000000000',
  memo: 'release funds for invoice #42',
});

3) Publish a State Update​

await client.sendStateUpdate({
  topicId: sTopic.topicId,
  stateHash: '0x…',
  epoch: 7,
  memo: 'post‑proposal state',
});

Reading Messages​

const recent = await client.getRecentMessages(cTopic.topicId, { limit: 10, order: 'desc', opFilter: 'flora_created' });
const latest = await client.getLatestMessage(cTopic.topicId, 'flora_created');

Use the browser client when you need on‑device signing and user consent flows; keep logic identical to Node by relying on the same builders and message shapes.