proposedCredential property
The proposed credential for this challenge.
This method returns null if there is no default credential for this challenge.
If you have previously attempted to authenticate and failed, this method returns the most recent failed credential.
If the proposed credential is not nil and returns true when you call its hasPassword method, then the credential is ready to use as-is.
If the proposed credential’s hasPassword method returns false, then the credential provides a default user name,
and the client must prompt the user for a corresponding password.
Implementation
URLCredential? proposedCredential;