In my app I have a webview in Page 2. When I press on the button in Page 1, I go to Page 2 and webview opens and I wrote username and password and log in to the web page. Then I go back to Page 1 for some reason. When I go back to to webview (Page 2) again, it reloads the web page and I have to log in again. How can I prevent reloading webview?