How do I validate a username/password in OnReceivedHttpAuthRequest?

Issue

I'm trying to store Windows credentials to login to an intranet webapp in a webview.

var login = Application.Context.GetSharedPreferences("Login", FileCreationMode.Private);
string username = login.GetString("username", null);
string password = login.GetString("password", null);

if (username != null && password != null)
    handler.Proceed(username, password);

But when the password is wrong it just keeps trying until the account is locked out. How do I check that the Proceed was unsuccessful so I can reprompt the user to enter in new credentials.

Solution

This is my suggestion:

int requestCount;
public override void OnReceivedHttpAuthRequest(WebView view, HttpAuthHandler handler, string host, string realm)
     {
         requestCount++;
         if(requestCount <3)
           {
             handler.Proceed(username, password);
           }
          else
           {
             //show a Dialog(with two edittext for input username and password) which notice credentials failure and reprompt the user to enter in new credentials
             //when you click Dialog's "Ok" reset requestCount to 0 and call "handler.Proceed(newUsername, newPassword);" 
             //when you click Dialog's "Cancel" call "handler.Cancel();"
           }
    }

Answered By - Leo Zhu - MSFT