wp_signon() is not working, admin cannot access wp-admin if he is not logged in on front?

Question

I am developing custom login/ logout functionality in my custom wp theme, the problem is that admin cannot directly access the wp-admin ie dashboard by typing example.com/wp-admin, but when admin log in on front and then type example.com/wp-admin only then he can access dashboard directly with out going to wp-login form.

function login_user($creds=""){  
$admin = current_user_can("manage_options");  
if (isset($creds)){  
wp_signon($creds,false);  
if ( is_wp_error($user) ){  
echo $user->get_error_message();  
}elseif(!$admin){  
wp_redirect(home_url());  
}  
}  
}  
add_action( 'after_setup_theme', 'login_user' );

Answer 1

function login_user($creds=""){  
$admin = current_user_can("manage_options");  
if (isset($creds)){  
$user= wp_signon($creds,false);  
if ( is_wp_error($user) ){  
echo $user->get_error_message();  
}elseif(!$admin){  
wp_redirect(home_url());  
}  
}  
}  
add_action( 'after_setup_theme', 'login_user' );

You are not setting a value for $user which should have been returned by wp_signon(). Try the code above.