> ## Documentation Index
> Fetch the complete documentation index at: https://docs.crossmint.com/llms.txt
> Use this file to discover all available pages before exploring further.

# ChainExplorerRegistry

> Flutter Abstract Final Class

**Abstract Final Class**

Best-effort explorer-link construction for transactions whose backend response omits an `explorerLink` field.

```dart theme={null}
abstract final class ChainExplorerRegistry
```

Kept separate from `CrossmintRuntimeWalletBase` so adding a new chain is
a one-file change and the 18 URL rows do not bloat the wallet base.

## Static Methods

### explorerLinkForTransaction

```dart theme={null}
static String? explorerLinkForTransaction({
  required String chain,
  required String hash,
})
```

Builds a `https://<explorer>/tx/<hash>` URL for the given chain + hash, or `null` when either the chain is not registered or the hash is empty.

### transactionHashFromRaw

```dart theme={null}
static String transactionHashFromRaw(CrossmintJsonMap raw)
```

Extracts a transaction hash from a wallet transaction's raw envelope.