调用 valueChangeListner 时出现 PropertyNotFoundException

Question

我有以下简单的selectOneMenu

<h:selectOneMenu id="shop" styleClass="tcell"
                 value="#{shoppingcenterControler.shoppingCenterScreenBean.shoppingcenterName}"
                 onchange="submit()"
                 valueChangeListener="#{shoppingcenterControler.shopChooseAction}">
  <f:selectItem itemValue="#{option.defaultShoppingcenter}" itemLabel="#{option.defaultShoppingcenter}"></f:selectItem>
  <f:selectItems value="#{shoppingCenterScreenBean.shoppingcenternames}"></f:selectItems>
</h:selectOneMenu>

当我在shoppingcenterControler 上使用@Named 注释时，我收到javax.el.PropertyNotFoundException 警告我Target Unreachable, identifier 'shoppingcenterControler' resolved to null。

当我使用 @ManagedBean 注释时，我收到警告：Property 'shopChooseAction' not found on type com.manageMyShopping.presentation.controler.ShoppingcenterControler，而 shopChooseAction 不是属性，它是：

public void shopChooseAction(ValueChangeEvent event){
    String shopName = getShoppingCenterScreenBean().getShoppingcenterName();
    if (!shopName.equals(defaultShopp)) {
        for (ShoppingCenterScreenBean thisShop : Shoppinglistcontroler.getShoppinglistScreenBean().getShoppingCentersScreenBean()) {
            if (!thisShop.getShoppingcenterName().equals(shopName)) {

                ShoppingCenterScreenBean newShoppingcenter = new ShoppingCenterScreenBean();
                newShoppingcenter.setShoppingcenterName(shopName);
                ShoppinglistScreenBean shoppinglist = Shoppinglistcontroler.getShoppinglistScreenBean();
                shoppinglist.getShoppingCentersScreenBean().add(newShoppingcenter); 
            }
        }
    }
}

我查看了不同的链接，包括以下内容： One somehow similar question

但是，它既不适合我，也不喜欢伪造的解决方案。我正在寻找一个真正的解决方案，我想了解

1. 为什么@Named 注释没有按预期运行？我已经在我的项目的pom.xml文件中添加了对应的依赖。
2. 为什么valueChnageListener 应该在方法名称上提出PropertyNotFoundException？

非常感谢任何帮助。

我的环境：Fedora 24、Java 1.8、apache-tomcat 8.0.33，我正在使用 Eclipse Mars。

Answer 1

我终于解决了我的问题。我没有使用valueChangeListener 作为标签<h:selectOneMenu> 的属性，而是使用了标签<f:valueChangeListener>，如下所示：

<h:selectOneMenu id="shop" styleClass="tcell"
                                value="#{shoppingcenterControler.shoppingCenterScreenBean.shoppingcenterName}"
                                onchange="submit()">
                                <f:selectItem itemValue="#{option.defaultShoppingcenter}" itemLabel="#{option.defaultShoppingcenter}"></f:selectItem>
                                <f:selectItems
                                    value="#{shoppingCenterScreenBean.shoppingcenternames}"></f:selectItems>
                                <f:valueChangeListener type="com.manageMyShopping.presentation.controler.ShoppingcenterListener"></f:valueChangeListener>
</h:selectOneMenu>

我已将类 ShoppingcenterListener 添加为：

public class ShoppingcenterListener implements ValueChangeListener {

FacesContext context = FacesContext.getCurrentInstance();
String bundleName = "com.manageMyShopping.presentation.elementaryBeans.itemOptions";
Locale local = context.getViewRoot().getLocale();
ResourceBundle bundle = ResourceBundle.getBundle(bundleName, local);
String defaultShop = bundle.getString("defaultShoppingcenter");

@Override
public void processValueChange(ValueChangeEvent event) throws AbortProcessingException {

    String shopName = event.getNewValue().toString();
    System.out.printf("ShoppingcenterNqme is: %s\n", shopName);
    if (!shopName.equals(defaultShop)) {
        for (ShoppingCenterScreenBean thisShop : Shoppinglistcontroler.getShoppinglistScreenBean().getShoppingCentersScreenBean()) {
            if (!thisShop.getShoppingcenterName().equals(shopName)) {

                ShoppingCenterScreenBean newShoppingcenter = new ShoppingCenterScreenBean();
                newShoppingcenter.setShoppingcenterName(shopName);
                ShoppinglistScreenBean shoppinglist = Shoppinglistcontroler.getShoppinglistScreenBean();
                shoppinglist.getShoppingCentersScreenBean().add(newShoppingcenter); 
            }
        }
    }
}

}

这解决了我的问题。我仍然不明白为什么 @Named 注释没有按预期运行。