Catching PrimeFaces's spinner value inside repeat structure

问题

I'm using Primefaces and spinner component. My problem is that the spinner value is not set in the bean, if it's inside an iteration structure. My spinner is inside ui:repeat. In the end, the problem is how to deal with different form controls mapping to the same property in bean.

<h:form>
    <ui:repeat var="item" value="#{myBean.items}">   
        <p:spinner size="2" min="1" max="50" style="width:75px" value="#{cartBean.quantityToOrder}"/>
        <p:commandButton value="Add to cart" action="#{cartBean.saveItemToCart(item)}" ajax="false"/>
    </ui:repeat>
</h:form>    

and my bean

@ManagedBean
@SessionScoped
public class CartBean extends BaseBean {

    private int quantityToOrder;

   //setter, getter...

   //When called quantityToOrder = 0 always
   public void saveItemToOrder(Item item) {
       quantityToOrder IS 0.
   }
}

I suspect it has to do with form submission, I have tried a form enclosing all elements in the collection and also a form enclosing any of the spinners + button. The generated client IDs are distinct for all spinners.

Any help would be appreciated.

回答1:

Put a System.out.println("quantity: " + quantityToOrder) on your setQuantityToOrder(int quantityToOrder) method and will will see the problem. The value of the last spinner will prevail over the others because all the spinners are pointed to the same property (cartBean.quantityToOrder).

Try moving the quantityToOrder to the Item as follows:

<h:form id="mainForm">
    <ui:repeat value="#{cartBean.items}" var="item">
        <p:outputLabel value="#{item.name}: " for="sp" />
        <p:spinner id="sp" size="2" min="1" max="50" style="width:75px" value="#{item.quantityToOrder}" />
        <p:commandButton value="Add to cart" action="#{cartBean.saveItemToOrder(item)}" process="@this, sp" update=":mainForm:total" />
        <br />
    </ui:repeat>
    Total: <h:outputText id="total" value="#{cartBean.quantityToOrder}" />
</h:form>

The cartBean:

import java.io.Serializable;
import java.util.ArrayList;
import java.util.List;
import javax.annotation.PostConstruct;
import javax.faces.bean.ManagedBean;
import javax.faces.bean.SessionScoped;

@ManagedBean
@SessionScoped
public class CartBean implements Serializable {

    private List<CartItem> items;

    private int quantityToOrder;

    @PostConstruct
    public void setup() {
        items = new ArrayList<CartItem>();
        items.add(new CartItem(1, "A"));
        items.add(new CartItem(2, "B"));
        items.add(new CartItem(3, "C"));
    }

    public void saveItemToOrder(CartItem item) {
        //do whatever you want to do with the item quantity.
        System.out.println("Qtd of " + item.getName() + ": " + item.getQuantityToOrder());

        //to calculte the qtd of items on the cart.
        quantityToOrder = 0;
        for (CartItem cartItem : items) {
            quantityToOrder += cartItem.getQuantityToOrder();
        }
    }

    public List<CartItem> getItems() {
        return items;
    }

    public void setItems(List<CartItem> items) {
        this.items = items;
    }

    public int getQuantityToOrder() {
        return quantityToOrder;
    }

    public void setQuantityToOrder(int quantityToOrder) {
        this.quantityToOrder = quantityToOrder;
    }

}

The CartItem:

import java.io.Serializable;

public class CartItem implements Serializable {

    private Integer id;

    private Integer quantityToOrder;

    private String name;

    public CartItem(Integer id, String name) {
        this.id = id;
        this.name = name;
        quantityToOrder = 0;
    }

    public Integer getId() {
        return id;
    }

    public void setId(Integer id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public Integer getQuantityToOrder() {
        return quantityToOrder;
    }

    public void setQuantityToOrder(Integer quantityToOrder) {
        this.quantityToOrder = quantityToOrder;
    }

    @Override
    public int hashCode() {
        int hash = 7;
        hash = 67 * hash + (this.id != null ? this.id.hashCode() : 0);
        return hash;
    }

    @Override
    public boolean equals(Object obj) {
        if (obj == null) {
            return false;
        }
        if (getClass() != obj.getClass()) {
            return false;
        }
        final CartItem other = (CartItem) obj;
        if (this.id != other.id && (this.id == null || !this.id.equals(other.id))) {
            return false;
        }
        return true;
    }

}

来源：https://stackoverflow.com/questions/21376514/catching-primefacess-spinner-value-inside-repeat-structure