错误：在WordPress中找不到选项页

Question

我正在尝试使WordPress options.php保存我在创建的设置页面上拥有的数据。我收到的错误是“ Error: Options Page Not Found”

<?php
/**
 * @package 
 * @version 1.6
 */
/*
Plugin Name: 
Plugin URI: 
Description: 
Author: Fahad Uddin
Version: 1.6
Author URI: 
Text Domain: 
*/

if ( is_admin() ){ // admin actions
  //add_action( 'admin_menu', 'add_mymenu' );
  add_action( 'admin_init', 'plugin_options_validate' );
} else {
  // non-admin enqueues, actions, and filters
}
?>
<style>
.ffs_valid{
    height: 15px;
    border-radius: 10px;
    width: 15px;
    display: inline-block;
    float: left;
    margin: 4px;
    background: green;
}
.ffs_invalid{
    height: 15px;
    border-radius: 10px;
    width: 15px;
    display: inline-block;
    float: left;
    margin: 4px;
    background: red;
}
.ffs_pause{
    height: 15px;
    border-radius: 10px;
    width: 15px;
    display: inline-block;
    float: left;
    margin: 4px;
    background: #dddddd;
}
td, th {
    border: 1px solid #dddddd;
    text-align: left;
    padding: 8px;
}
</style>
<?php
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Site Report";
function ffs_page_view() {
    $page_views=0;
    if(get_option('page_view'))
    {
        $page_views= get_option('page_view');
    }
    else
        update_option( 'page_view', 0 );
    $page_views++;
    $time = get_the_time();
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Site Report";
    $message = "Page View";
    wp_mail( "ifahaduddin@gmail.com", $subject, $message);
    update_option( 'page_view',$page_views);
    update_option( 'page_view_last',$time);
}

add_action( 'get_header', 'ffs_page_view' );

function ffs_single_product_view() {
    $single_product=0;
    if(get_option('single_product'))
    {
        $single_product= get_option('single_product');
    }
    else
        update_option( 'single_product', 0 );
    $single_product++;
    $time = get_the_time();
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Site Report";
    $message = "Single Product Viewed";
    wp_mail( $ffs_to, $subject, $message);
    update_option( 'single_product',$single_product);
    update_option( 'single_product_last',$time);
}

add_action( 'woocommerce_before_single_product', 'ffs_single_product_view' );

function ffs_user_checkout() {
    $checkout=0;
    if(get_option('checkout'))
    {
        $checkout= get_option('checkout');
    }
    else
        update_option( 'checkout', 0 );
    $checkout++;
    $time = get_the_time();
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Site Report";
    /** These are the lyrics to Hello Dolly */
    $message = "Checkout";
    wp_mail( $ffs_to, $subject, $message);
    update_option( 'checkout',$checkout);
    update_option( 'checkout_last',$time);
}

add_action( 'woocommerce_before_checkout_billing_form', 'ffs_user_checkout' );


function ffs_coupon() {
    $coupon=0;
    if(get_option('coupon'))
    {
        $coupon= get_option('coupon');
    }
    else
        update_option( 'coupon', 0 );
    $coupon++;
    $time = get_the_time();
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Site Report";
    /** These are the lyrics to Hello Dolly */
    $message = "Coupon applied";
    wp_mail( $ffs_to, $subject, $message);
    update_option( 'coupon',$coupon);
    update_option( 'coupon_last',$time);
}

add_action( 'woocommerce_applied_coupon', 'ffs_coupon' );

function ffs_add_cart() {
    $cart=0;
    if(get_option('cart'))
    {
        $cart= get_option('cart');
    }
    else
        update_option( 'cart', 0 );
    $cart++;
    $time = get_the_time();
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Site Report";
    /** These are the lyrics to Hello Dolly */
    $message = "Added to cart";
    wp_mail( $ffs_to, $subject, $message);
    update_option( 'cart',$cart);
    update_option( 'cart_last',$time);  
}

add_action( 'woocommerce_add_to_cart', 'ffs_add_cart' );

/*
function ffs_out_stock() {
    $out_stock=0;
    if(get_option('out_stock'))
    {
        $out_stock= get_option('out_stock');
    }
    else
        update_option( 'out_stock', 0 );
    $out_stock++;
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Out of stock";
    update_option( 'out_stock',$out_stock);
}

add_action( 'woocommerce_no_stock', 'ffs_out_stock' );
*/
function ffs_user_ordered() {
    $orders=0;
    if(get_option('orders'))
    {
        $orders= get_option('orders');
    }
    else
        update_option( 'orders', 0 );
    $orders++;
    $time = get_the_time();
    $ffs_to="ifahaduddin@gmail.com";
    $subject = "Orders";
    /** These are the lyrics to Hello Dolly */
    $message = "Ordered";
    wp_mail( $ffs_to, $subject, $message);
    update_option('orders',$orders);
    update_option( 'orders_last',$time);
}

add_action( 'woocommerce_thankyou', 'ffs_user_ordered' );

add_action('admin_menu', 'plugin_admin_add_page');
function plugin_admin_add_page() {

add_options_page('Woo Alerts Heartbeat', 'Woo Alerts Heartbeat', 'manage_options', 'plugin', 'plugin_options_page');
}

?>
<?php // display the admin options page
function plugin_options_page() {
?>
<div>
<h2>WooCommerce Heartbeat</h2>
Measure your eCommerce site
<form method="post" action="options.php"> 
<?php // settings_fields( 'plugin_options_validate' );?>
<?php  // do_settings_sections( 'plugin_options_validate' );?>

// some html here and form to show on the page along with fields
<?php submit_button(); ?>
</form>

 <!--
<input name="Submit" type="submit" value="<?php esc_attr_e('Save Changes'); ?>" />
</form></div>
 -->
<?php
}?>

<?php // add the admin settings and such
add_action('admin_init', 'plugin_admin_init');
function ffs_is_valid(){
    return "ffs_valid";
}
function plugin_admin_init(){
register_setting( 'plugin_options', 'plugin_options', 'plugin_options_validate' );
//register_setting('bp-settings-group', 'bp_options', 'bp_options_sanitize');
//add_settings_section('plugin_main', 'Main Settings', 'plugin_options_validate', 'plugin');
//add_settings_field('plugin_text_string', 'Plugin Text Input', 'plugin_options_validate', 'plugin', 'plugin_main');
}

function plugin_options_validate(){

}


?>