How to do Gateway authentication using SAPUI5?

Hi,

I am doing  application using Net weaver gateway and sapui5 . In that I am passing username and password along with service URL  like below.

var oModel = new sap.ui.model.ODataModel(sServiceUrl, true, "username", "pwd");

Now I want to pass these username and password values dynamically.

For that I designed login screen and passing that username and password dynamically  to the ODataModel when click on login Button. When I am sending proper values it goes to back end and working fine.

  But when I enter wrong username and passwords I am getting browser related Login screen on the top of my login screen and when I cancel that I am getting 401 unauthorized error .

Please find the below images

• How to prevent that browser related authentication screen when End user enter wrong inputs?
• How to catch that 401 error  if login failed?

Please help me to resolve.

Thanks&Regards

Sridevi