How to debug 'Notice: Undefined index' on a Request['action']

Question

I use the next code in order to save the options of my theme (by using the Wp Settings API), but when I debug it, I get the 'Notice: Undefined index: action' error/notification.

In order to fix it, I added "isset()" before the first $_REQUEST. Now the notification is not apperaring, but the options are not saved when I click the 'SAVE' button. What I'm doing wrong? How can I fix it? Thank you in advance.

function mytheme_add_admin() {
global $themename, $options;
if ( isset( $_GET['page'] ) && $_GET['page'] === basename(__FILE__) ) {
    if(isset( $_REQUEST["action"] ) && $_REQUEST["action"] === 'save') {
            foreach ($options as $value) {
                update_option( $value['id'], $_REQUEST[ $value['id'] ] ); }
            foreach ($options as $value) {
                if( isset( $_REQUEST[ $value['id'] ] ) ) { update_option( $value['id'], $_REQUEST[ $value['id'] ]  ); } else { delete_option( $value['id'] ); } }
            header("Location: themes.php?page=theme-options.php&saved=true");
            die;
    } else if(isset( $_REQUEST["action"] ) && $_REQUEST["action"] === 'reset') {
        foreach ($options as $value) {
            delete_option( $value['id'] ); }
        header("Location: themes.php?page=theme-options.php&reset=true");
        die;
    }
}
add_theme_page($themename." Options", "".$themename." Options", 'edit_themes', basename(__FILE__), 'mytheme_admin');
}

Answer 1

A little bit of simple debugging and everything is clear.

$REQUEST['action'] is set in this case, so my first guess wasn't true, but... Its value is 'save' and not 'page' nor 'reset'. So your code does exactly nothing, because there is no if part for such value;