SshConnecitonParameters scp;
scp.host = ...;
scp.userName = ... ;
...etc...
SshConnection *conn = new SshConnection(&scp);
SftpChannel *sftp = conn.createSftpChannel();
SftpJobId id = sftp->downloadFile(remoteName, localName, SftpOverwriteMode::SftpOverwriteExisting);
connect( sft, SIGNAL(finished(..)), this, SLOT(sftpFinished(..));