getSubDirectoryFilePath static method
This method asynchronously retrieves the wallet directory path by calling createOrGetFolderInWalletDir, and then constructs a file path by concatenating the wallet path with the provided fileName. The resulting file path is returned as a Future-wrapped String.
Implementation
static Future<String> getSubDirectoryFilePath(String walletDirName, String walletName, String fileName) async {
final String walletPath = await createOrGetFolderInWalletDir(walletDirName, walletName);
String filePath = path.join(walletPath, fileName);
return filePath;
}