ThymileAF-如何将固定对象发布到控制器？

Question

我有一个复选框的集合，每个复选框代表一个“产品”的顶部。我想传递一个修改的产品对象，勾选的浇头存储为selectedToppings。

我已经尝试了下面的代码，但不起作用。问题是我正在传递一个空的“product”对象，并且只存储复选框值（作为“selectedToppings”）。如何将“product”对象与“selectedToppings”一起传递？

html（片段）：

            <form method="post" th:object="${product}" th:action="@{/addItemToCart}">
            <div class="modal-body">
                    <div class="card-body">
                        <div th:each="topping : ${product.toppings}">
                            <div class="custom-control custom-checkbox my-1 mr-sm-2">
                                <input type="checkbox" class="custom-control-input" th:id="${topping} + ${product.id}" name="toppings" th:value="${topping}" />
                                <label class="custom-control-label" th:for="${topping} + ${product.id}" th:text="${topping}"></label>
                            </div>
                        </div>
                    </div>
                </div>
                <div class="modal-footer">
                    <button type="submit" class="btn btn-block btn-success">Add to Shopping Cart</button>
                </div>
            </form>

控制器：

@RequestMapping(value="/addItemToCart", method=RequestMethod.POST)
public String addItemToCart(@ModelAttribute("product") Product product, @RequestParam("toppings") List<String> toppings)
{
    Product newItem = product;
    newItem.setSelectedToppings(toppings);
    addItemToBucket(newItem);

    return "redirect:/menu";
}

实体：

public class Product
{
private String id;
private String name;
private String description;
private Double price;
private List<String> toppings;
private List<String> selectedToppings;

public Product()
{
 this.id = "";
 this.name = "";
 this.description = "";
 this.price = 0.0;
 this.toppings = new ArrayList<String>();
 this.selectedToppings = new ArrayList<String>();
}
public Product(String id, String name, String description, Double price, List<String> toppings)
{
    this.id = id;
    this.name = name;
    this.description = description;
    this.price = price;
    this.toppings = toppings;
    this.selectedToppings = new ArrayList<String>();
}
//...getters & setters
}

Answer 1

我不确定，我是否完全理解你的问题。

如果您在

th:field=“*{toppings}”

我现在注意到的一件事是，您缺少产品类的getter/setter。