Google登录在Android应用程序中“检查首次登录”和“注销”问题

I am making an android application, when the user installs the application, he/she needs to sign-in with google account, after successful logged-in , he/she will be redirected to the dashboard page. If he/she closes application and opens it again and if they are already logged in then dashboard activity should be shown itself. Also I have a drawerLayout in my dashboard activity having a "Sign-out" button from which the user can log out and login activity is opened up again.I am making an android application, when the us