WooCommerce: Coupon doens't work in cart if I wrap it in collapse element

Question

I want to hide the coupon field in the cart. To do so, I've wrapped it in a Bootstrap collapse element and added display:none to the existing coupon field.

EDIT: After the comment from @gael (WooCommerce: Coupon doens't work in cart if I wrap it in collapse element), I figuered out, that the form works if I show it in other places of the template. But now it doesn't show any success or error messages anymore?!

Here's my code:

<?php

add_action( 'woocommerce_after_cart_table', 'display_coupon_form_below_proceed_checkout', 50 );

function display_coupon_form_below_proceed_checkout() {
   ?>

    <small><a class="text-muted" data-toggle="collapse" href="#collapseCartCoupon" role="button" aria-expanded="false" aria-controls="collapseCartCoupon"><?php esc_attr_e( 'Coupon code', 'woocommerce' ); ?></a></small>

        <form class="woocommerce-coupon-form" action="<?php echo esc_url( wc_get_cart_url() ); ?>" method="post">
            <div class="collapse" id="collapseCartCoupon">
            <?php if ( wc_coupons_enabled() ) { ?>
            <div class="coupon under-proceed">
                <input type="text" name="coupon_code" class="input-text" id="coupon_code" value="" placeholder="<?php esc_attr_e( 'Coupon code', 'woocommerce' ); ?>" style="width: 100%" />
                <button type="submit" class="button" name="apply_coupon" value="<?php esc_attr_e( 'Apply coupon', 'woocommerce' ); ?>" style="width: 100%"><?php esc_attr_e( 'Apply coupon', 'woocommerce' ); ?></button>
            </div>
            <?php } ?>
            </div>
        </form>

    <style>
        .woocommerce table.shop_table .coupon {display: none !important;}
    </style>
    <?php
}

Answer 1

I would override the Cart page on WooCommerce to wrap the Coupon in a collapse element.

This template can be overridden by copying the file from wp-content/plugins/woocommerce/templates/cart/cart.php it to wp-content/themes/yourtheme/woocommerce/cart/cart.php.

Then from line 142 to 150 in WooCommerce v4, you can insert your snippet like so:

<?php if ( wc_coupons_enabled() ) { ?>
    <small><a class="text-muted" data-toggle="collapse" href="#collapseCartCoupon" role="button" aria-expanded="false" aria-controls="collapseCartCoupon"><?php esc_attr_e( 'Coupon code', 'woocommerce' ); ?></a></small>
    <div class="coupon collapse"  id="collapseCartCoupon">
        <label for="coupon_code"><?php esc_html_e( 'Coupon:', 'woocommerce' ); ?></label> <input type="text" name="coupon_code" class="input-text" id="coupon_code" value="" placeholder="<?php esc_attr_e( 'Coupon code', 'woocommerce' ); ?>" /> <button type="submit" class="button" name="apply_coupon" value="<?php esc_attr_e( 'Apply coupon', 'woocommerce' ); ?>"><?php esc_attr_e( 'Apply coupon', 'woocommerce' ); ?></button>
        <?php do_action( 'woocommerce_cart_coupon' ); ?>
    </div>
<?php } ?>

Since my theme is already using Bootstrap, the collapse class already hides the whole div so I didn't have to add your inline style.

I did test to move it into a new <tr> under the table and the coupon code is still working. I guess it only have to be inside the <form>...</form> to be available.

Also note that warning from WooCommerce on top of the template file:

 * HOWEVER, on occasion WooCommerce will need to update template files and you
 * (the theme developer) will need to copy the new files to your theme to
 * maintain compatibility. We try to do this as little as possible, but it does
 * happen. When this occurs the version of the template file will be bumped and
 * the readme will list any important changes.