1

以下 XHTML 通过 将选定的值设置<p:selectOneMenu>为请求范围的 bean <p:remoteCommand>。

<h:form id="languageForm" prependId="true">

    <pe:blockUI target=":body" widgetVar="blockBodyUIWidget">
        <h:panelGrid columns="2">
            <h:graphicImage library="default" name="images/ajax-loader1.gif" class="block-ui-image"/>
            <h:outputText value="#{messages['blockui.panel.message']}" class="block-ui-text"/>
        </h:panelGrid>
    </pe:blockUI>

    <p:selectOneMenu id="languages" value="#{localeBean.language}" onchange="changeLanguage([{name:'language', value:this.value}]);">
        <f:selectItem itemValue="en" itemLabel="#{messages['languages.english']}" />
        <f:selectItem itemValue="hi" itemLabel="#{messages['languages.hindi']}" />
    </p:selectOneMenu>

    <p:remoteCommand name="changeLanguage" process="@this" update="@none" onstart="PF('blockBodyUIWidget').block();" oncomplete="PF('blockBodyUIWidget').unblock();" action="#{intermediateLocaleBean.localeAction}"/>
</h:form>

对应的 JSF 托管 bean：

@ManagedBean
@RequestScoped
public final class IntermediateLocaleBean
{
    @ManagedProperty("#{param.language}")
    private String language;
    @ManagedProperty("#{localeBean}")
    private LocaleBean localeBean;  //Injecting another session scoped bean here.

    public IntermediateLocaleBean() {}

    public void setLanguage(String language) {
        this.language = language;
    }

    public void setLocaleBean(LocaleBean localeBean) {
        this.localeBean = localeBean;
    }

    public String localeAction()
    {
        localeBean.setLocale(language.equals("hi")?new Locale(language, "IN"):new Locale(language));
        return FacesContext.getCurrentInstance().getViewRoot().getViewId() + "?faces-redirect=true";
    }
}

该language属性被初始化为 中的选定语言<p:selectOneMenu>。这一切都完成了，因为它是一个 JSF 托管 bean。

如果，bean 由 Spring 维护，如下所示？

@Controller
@Scope("request")
public final class IntermediateLocaleBean
{
    //Do something to initialize the property - language.
    //@ManagedProperty would not work as this bean is managed by Spring.
    //It is not initialized to the selected language in <p:selectOneMenu>.
    //It is null.

    private String language;

    //The session scoped bean is injected using the @Autowired annotation as follows.

    @Autowired
    private final transient LocaleBean localeBean=null;

    public IntermediateLocaleBean() {}

    public void setLanguage(String language) {
        this.language = language;
    }

    public String localeAction()
    {
        localeBean.setLocale(language.equals("hi")?new Locale(language, "IN"):new Locale(language));
        return FacesContext.getCurrentInstance().getViewRoot().getViewId() + "?faces-redirect=true";
    }
}

如何在此 bean中将language属性初始化为所选语言？<p:selectOneMenu>

4

1 回答 1

2

传统上，language请求参数的参数值可以使用

FacesContext context = FacesContext.getCurrentInstance();
String language = context.getExternalContext().getRequestParameterMap().get("language");

像下面这样，

@Controller
@Scope("request")
public final class IntermediateLocaleBean
{
    @Autowired
    private final transient LocaleBean localeBean=null;

    public IntermediateLocaleBean() {}

    public void setLanguage(String language) {
        this.language = language;
    }

    public String localeAction()
    {
        String language = FacesContext.getCurrentInstance().getExternalContext().getRequestParameterMap().get("language");
        localeBean.setLocale(language.equals("hi")?new Locale(language, "IN"):new Locale(language));

        return FacesContext.getCurrentInstance().getViewRoot().getViewId() + "?faces-redirect=true";
    }
}

但我个人不喜欢公开整个请求，FacesContext除非绝对必要。

Spring中有一个org.springframework.beans.factory.annotation.Value注解可以配合Spring表达式语言来获取请求参数如下。

@Controller
@Scope("request")
public final class IntermediateLocaleBean
{
    @Value("#{request.getParameter('language')}") //Exposing the value of language.
    private String language;

    @Autowired
    private final transient LocaleBean localeBean=null;

    public IntermediateLocaleBean() {}

    public void setLanguage(String language) {
        this.language = language;
    }

    public String localeAction()
    {
        localeBean.setLocale(language.equals("hi")?new Locale(language, "IN"):new Locale(language));
        return FacesContext.getCurrentInstance().getViewRoot().getViewId() + "?faces-redirect=true";
    }
}

language作为请求参数提供的值<p:remoteCommand>现在可以使用注释在此 bean 中使用（在我的情况下不需要@Valuegetter 方法）。language

如果还有其他可用的，请建议或添加另一个答案！

于 2014-04-01T11:56:34.727 回答