我有一个使用.on（）的脚本，因为元素是动态生成的，在某些移动设备上不起作用。您可以尝试lilwhats.com/demo。请使用此网站进行测试：https://www.browserling.com/ 选择旧版本的android，也可以选择windows vista>internet explorer v9
restaurant.php

($allow_order
                                ? '<div class="add-menu">
                                        <div class="add-btn add-item-to-order">
                                            <span>' . $lang['ADD'] . '</span>
                                            <i class="icon-feather-plus"></i>
                                        </div>
                            ' .
                                (!empty($extras) ? '<span class="customize">' . $lang['CUSTOMIZABLE'] . '</span>' : '')
                                . '        </div>'
                                : '') .

                            '

theme.js

// add menu to order
    $(document).on('click','.add-item-to-order', function (e) {
        e.preventDefault();

        var $add_customize = $('<div class="add-btn add-item-btn">' +
            '<div class="wrapper h-100">' +
            '<div class="addition menu-order-quantity-decrease">' +
            '<i class="icon-feather-minus"></i>' +
            '</div>' +
            '<div class="count">' +
            '<span class="num menu-order-quantity">1</span>' +
            '</div>' +
            '<div class="addition menu-order-quantity-increase">' +
            '<i class="icon-feather-plus"></i>' +
            '</div>' +
            '</div>' +
            '</div>'),
            $item = $(this).closest('.section-menu'),
            item_id = $item.data('id'),
            name = $item.data('name'),
            description = $item.data('description'),
            price = $item.data('price'),
            amount = $item.data('amount'),
            order_price = Number(amount),
            extras = TOTAL_MENUS[$item.data('id')].extras || [],
            order_data = JSON.parse(localStorage.getItem('quickqr_order')),
            random_id = randomId(10);

        $item.data('cart_id',random_id);
        if(extras.length == 0){
            order_data[random_id] = {
                'id': item_id,
                'item_name': name,
                'item_price': amount,
                'extras': {},
                'quantity': 1
            };

            localStorage.setItem('quickqr_order', JSON.stringify(order_data));

            $item.find('.add-menu').html($add_customize);
        } else {
            $menuCustomize.find('h4').html(name);
            $menuCustomize.find('.customize-item-description').html(description);
            $('#order-price').html(formatPrice(amount));
            $('#menu-order-quantity').text(1);

            var $extra_wrapper = $('#customize-extras');
            $extra_wrapper.html('');

            for (var i in extras) {
                if (extras.hasOwnProperty(i)) {
                    var $extra_tpl = $(
                        '<div class="extras menu-extra-item">' +
                        '<span class="extra-item-title"></span>' +
                        '<div class="d-flex align-items-center">' +
                        '<span class="mr-2 extra-item-price"></span>' +
                        '<div class="custom-control custom-checkbox mr-sm-2">' +
                        '<input type="checkbox" class="custom-control-input" id="customControl">' +
                        '<label class="custom-control-label" for="customControl"></label>' +
                        '</div>' +
                        '</div>' +
                        '</div>');

                    $extra_tpl.find('.custom-control-input').attr('id', 'checkbox' + extras[i].id);
                    $extra_tpl.find('label').attr('for', 'checkbox' + extras[i].id);
                    $extra_tpl.find('.extra-item-title').html(extras[i].title);
                    $extra_tpl.find('.extra-item-price').html(formatPrice(extras[i].price));
                    $extra_tpl.data('price', extras[i].price);
                    $extra_tpl.data('id', extras[i].id);

                    $extra_tpl.find('.custom-control-input').on('change',function () {
                        $('#menu-order-quantity').text(1);
                        calculateOrderPrice(amount);

                    });
                    $extra_wrapper.append($extra_tpl);
                }
            }

            $menuCustomize.find('.menu-order-quantity-decrease').off().on('click', function (e) {
                e.stopPropagation();
                var quatity = Number($('#menu-order-quantity').text()) - 1;
                if(quatity == 0){
                    quatity = 1;
                }
                $('#menu-order-quantity').text(quatity);
                calculateOrderPrice(order_price);
            });
            $menuCustomize.find('.menu-order-quantity-increase').off().on('click', function (e) {
                e.stopPropagation();
                $('#menu-order-quantity').text(Number($('#menu-order-quantity').text()) + 1);
                calculateOrderPrice(order_price);
            });

            $('#add-order-button').off().on('click', function (e) {
                calculateOrderPrice(order_price);
                var price = $('#order-price').html();
                var order_data = JSON.parse(localStorage.getItem('quickqr_order'));

                // this order's extras
                var extras = {};
                $('.menu-extra-item').each(function () {
                    if($(this).find('.custom-control-input').is(':checked')){
                        extras[randomId(10)] = {
                            'id': $(this).data('id'),
                            'name': $(this).find('.extra-item-title').html(),
                            'price': $(this).data('price')
                        };
                    }
                });

                order_data[random_id] = {
                    'id': item_id,
                    'item_name': name,
                    'item_price': amount,
                    'extras': extras,
                    'quantity': $('#menu-order-quantity').text()
                };

                localStorage.setItem('quickqr_order', JSON.stringify(order_data));

                $add_customize.find('.menu-order-quantity').text($('#menu-order-quantity').text());
                $item.find('.add-menu').html($add_customize);

                manageViewOrder();
                $('.overlay').trigger('click');
            });

            $menuCustomize.addClass('active');
            $('.overlay').addClass('active');
            $('body').addClass('noscroll');
        }
        manageViewOrder();
    });

我真的很感谢你的帮助

$order_tpl.find('.menu-order-quantity-decrease').off().on('click', function (e) {
                        e.stopPropagation();
                        var $item = $(this).closest('.section-menu');
                        var $quantity = $item.find('.menu-order-quantity');
                        var quantity = Number($quantity.text()) - 1;
                        var cart_key = $item.data('cart_id');
                        var $menu_item = $('.section-menu[data-id="' + order_data[cart_key]['id'] + '"]');
                        if (quantity == 0) {
                            var $add_btn = $('<div class="add-btn add-item-to-order">' +
                                '<span>' + LANG_ADD + '</span>' +
                                '<i class="icon-feather-plus"></i>' +
                                '</div>');
                            $menu_item.find('.add-menu').html($add_btn);
                            delete order_data[cart_key];

                        } else {
                            $menu_item.find('.menu-order-quantity').text(quantity);
                            order_data[cart_key]['quantity'] = quantity;
                        }

                        localStorage.setItem('quickqr_order', JSON.stringify(order_data));
                        generateViewOrder();
                    });