wocommerce calculate shipping not being called - php

Question

Hi have a wocommerce plugin, While changing the payment method. the cost for shipping my function calculate_shipping is not being called. and therefore shipping methods are not updating with appropriate cost
here are some samples from my code.
public function __construct() {
add_action('woocommerce_review_order_before_payment', array($this, 'update_shipping_charges'), 1);
}
public function update_shipping_charges() {
// jQuery code
?>
<script type="text/javascript">
(function ($) {
$('form.checkout').on('change', 'input[name^="payment_method"]', function () {
// Set the select value in a variable
$('body').trigger('update_checkout');
//testing
$('body').on('updated_checkout', function() {
console.log('updated');
});
});
})(jQuery);
</script>
<?php
}

Answer 1

Try wrapping everything inside the init hook. Maybe the code gets executed too early:
public function __construct() {
add_action( 'init', [ $this, 'init_action' ] );
}
public function init_action(): void {
add_action( 'woocommerce_review_order_before_payment', [ $this, 'update_shipping_charges' ], 1 );
}
public function update_shipping_charges(): void {
// jQuery code
?>
<script type="text/javascript">
(function ( $ ) {
$( 'form.checkout' ).on( 'change', 'input[name^="payment_method"]', function () {
// Set the select value in a variable
let body = $( 'body' );
body.trigger( 'update_checkout' );
//testing
body.on( 'updated_checkout', function () {
console.log( 'updated' );
} );
} );
})( jQuery );
</script>
<?php
}
You could try multiple hooks if init don't works:
woocommerce_loaded
woocommerce_init
plugins_loaded <- I use this one in my plugins for example

Answer 2

Please try the following (Add to functions.php or via Code Snippets plugin)
function kia_checkout_on_payment_change() {
wp_add_inline_script( 'wc-checkout', '
jQuery( document.body ).on( "payment_method_selected", function() {
jQuery( "form.checkout" ).trigger( "update_checkout", { update_shipping_method: true } );
console.log("payment selected");
} );
'
);
}
add_action( 'wp_enqueue_scripts', 'kia_checkout_on_payment_change' );
A couple notes....
We're adding the script right after the wc-checkout script is loaded.
We're listening for the WooCommerce checkout script's payment_method_selected (but yes, it's a core Woo trigger in the checkout) trigger which should fire when the payment method is changed
We're explicitly passing some arguments to the update_checkout function.
Don't have any shipping methods set up locally to test it properly, but I hope it points you in the right direction.