As per google doc: When the google sign in button is loaded, it immediately checks to see if the user has authorized the application. This check is called "immediate mode" and if successful, the Google servers return an access token and pass a new authorization result object to the callback. If the button cannot make an immediate-mode authorization, the user must click the sign-in button to trigger the access flow.
My Google Plus signin button is part of header and on logout the home page is loaded,It again renders google plus button resulting in automatic login. User is never logged out due to this. How is it possible to allow login when when G Plus button is clicked and not when when the G Plus buttom reders itself?