如何在主题functions.php中对接WooCommerce插件及移除Amazon Pay动作

Hey there! Let's break down your two WooCommerce questions with practical, actionable solutions:

WooCommerce is built to be super extensible, and your theme's functions.php is the perfect place to hook into its system. Here's how to do it right:

• Wait for WooCommerce to load first
  Never run WooCommerce-related code before the plugin is initialized—this avoids fatal errors. Use the woocommerce_loaded hook to wrap your code:

  add_action( 'woocommerce_loaded', 'my_theme_woocommerce_setup' );
  function my_theme_woocommerce_setup() {
      // All your WooCommerce integration code goes here
  }
  

• Leverage WooCommerce's hooks and filters
  WooCommerce provides hundreds of actions (for adding content/behavior) and filters (for modifying data). For example:

  • Add a custom checkout field:

    add_action( 'woocommerce_after_order_notes', 'my_theme_add_custom_checkout_field' );
    function my_theme_add_custom_checkout_field( $checkout ) {
        echo '<div id="custom_checkout_field"><h3>' . __('Special Instructions') . '</h3>';
        woocommerce_form_field( 'special_instructions', array(
            'type' => 'textarea',
            'class' => array('form-row-wide'),
            'label' => __('Tell us anything we need to know'),
            'placeholder' => __('e.g., Leave package at back door'),
        ), $checkout->get_value( 'special_instructions' ));
        echo '</div>';
    }
    

  • Modify product prices dynamically:

    add_filter( 'woocommerce_get_price_html', 'my_theme_modify_product_price', 10, 2 );
    function my_theme_modify_product_price( $price_html, $product ) {
        if ( is_user_logged_in() ) {
            $discounted_price = $product->get_price() * 0.9; // 10% discount for logged-in users
            return wc_price( $discounted_price );
        }
        return $price_html;
    }
    

• Directly access WooCommerce classes (when needed)
  For deeper integrations (like working with orders or products), use WooCommerce's built-in classes. Just make sure they're loaded first:

  add_action( 'woocommerce_thankyou', 'my_theme_send_custom_order_notification' );
  function my_theme_send_custom_order_notification( $order_id ) {
      $order = wc_get_order( $order_id );
      if ( $order ) {
          $customer_email = $order->get_billing_email();
          // Send a custom email or update external systems here
          wp_mail( $customer_email, __('Thanks for your order!'), __('We appreciate your business.') );
      }
  }
  

I’ve been in your shoes—removing plugin actions can be tricky if you don’t match the exact parameters. Here’s how to fix it:

First, diagnose the plugin's code #

From what you said, the Amazon Pay plugin adds the button via an action in /woocommerce-gateway-amazon-payments-advanced.php. Typically, it looks something like this (using a class method):

add_action( 'woocommerce_checkout_before_customer_details', array( $this, 'render_amazon_pay_button' ), 10 );

The key here is to match three things exactly when removing: the hook name, the callback (including the class instance), and the priority.

The correct removal & repositioning code #

Add this to your theme's functions.php:

add_action( 'plugins_loaded', 'my_theme_move_amazon_pay_button', 11 );
function my_theme_move_amazon_pay_button() {
    // Get the Amazon Pay gateway instance from WooCommerce
    $amazon_gateway = WC()->payment_gateways()->get_gateway( 'amazon_payments_advanced' );
    
    if ( $amazon_gateway ) {
        // Remove the original action—match hook, callback, and priority exactly
        remove_action( 'woocommerce_checkout_before_customer_details', array( $amazon_gateway, 'render_amazon_pay_button' ), 10 );
        
        // Add it to your desired location—adjust the hook and priority as needed
        // Example: Move to after the order review section
        add_action( 'woocommerce_checkout_after_order_review', array( $amazon_gateway, 'render_amazon_pay_button' ), 10 );
    }
}

Common mistakes to avoid #

• Wrong priority: If the plugin uses priority 10, your removal code needs to run after that—hence using 11 on plugins_loaded.
• Mismatched callback: If the plugin uses a class method, you can’t just use the function name—you need to pass the class instance (which we get via WC()->payment_gateways()->get_gateway()).
• Running too early: If you try to remove the action before the plugin adds it, it won’t work. plugins_loaded ensures all plugins are loaded first.

内容的提问来源于stack exchange，提问作者logrexton