Fix loading paymentMethodID after DOM ready

Author: mrbrdo

app/assets/javascripts/spree/backend/spree_paypal_express.js

@@ -16,7 +16,7 @@ SpreePaypalExpress = {
   }
 }
 
-$(document).ready(function() {
+Spree.ready(function() {
   checkedPaymentMethod = $('[data-hook="payment_method_field"] input[type="radio"]:checked');
   SpreePaypalExpress.hideSettings(checkedPaymentMethod);
   paymentMethods = $('[data-hook="payment_method_field"] input[type="radio"]').click(function (e) {

app/assets/javascripts/spree/frontend/spree_paypal_express.js

@@ -23,7 +23,8 @@ SpreePaypalExpress = {
   }
 }
 
-$(document).ready(function() {
+Spree.ready(function() {
+  SpreePaypalExpress.paymentMethodID = $('#paypal_button').data('payment-method-id');
   SpreePaypalExpress.updateSaveAndContinueVisibility();
   paymentMethods = $('div[data-hook="checkout_payment_step"] input[type="radio"]').click(function (e) {
     SpreePaypalExpress.updateSaveAndContinueVisibility();

app/views/spree/checkout/payment/_paypal.html.erb

@@ -1,6 +1,2 @@
 
-<%= link_to(image_tag("https://www.paypal.com/en_US/i/btn/btn_xpressCheckout.gif"), paypal_express_url(:payment_method_id => payment_method.id), :method => :post, :id => "paypal_button") %>
-
-<script>
-  SpreePaypalExpress.paymentMethodID = "<%= payment_method.id %>"  
- </script>
+<%= link_to(image_tag("https://www.paypal.com/en_US/i/btn/btn_xpressCheckout.gif"), paypal_express_url(:payment_method_id => payment_method.id), :method => :post, :id => "paypal_button", data: { 'payment-method-id' => payment_method.id }) %>