如何通过使用支持组件将属性从复合组件传递到支持bean? [英] How do I pass an attribute from composite component to backing bean by using backing component?

问题描述

我的facelet页面中包含以下代码:

I have the following code in my facelet page:

  <hc:rangeChooser1 id="range_chooser" 
                    from="#{testBean.from}"
                    to="#{testBean.to}"
                    listener="#{testBean.update}"
                    text="#{testBean.text}">
        <f:ajax event="rangeSelected"
                execute="@this"
                listener="#{testBean.update}"                   
                render=":form:growl range_chooser"/>
    </hc:rangeChooser1>

这是我的复合组件:

<ui:component xmlns="http://www.w3.org/1999/xhtml"
    xmlns:f="http://java.sun.com/jsf/core"
    xmlns:h="http://java.sun.com/jsf/html"
    xmlns:ui="http://java.sun.com/jsf/facelets"
    xmlns:cc="http://java.sun.com/jsf/composite"
    xmlns:p="http://primefaces.org/ui">
    <cc:interface componentType="rangeChooser">
        <!-- Define component attributes here -->
        <cc:clientBehavior name="rangeSelected" event="change" targets="hiddenValue"/>
        <cc:attribute name="from" type="java.util.Calendar"/>
        <cc:attribute name="to" type="java.util.Calendar"/>
        <cc:attribute name="text" type="java.lang.String"/>

    </cc:interface>


    <cc:implementation>

        <div id="#{cc.clientId}">
                 ...
                <p:inputText id="hiddenValue" value="#{cc.attrs.text}"/>
                 ...
        </div>
    </cc:implementation>
</ui:component>

如何将属性from，to和text从复合组件传递到支持bean?我的意思是将这些值注入支持组件，而不是通过

How do I pass attributes from, to and text from composite component to backing bean? I mean inject these values in backing component, and not through

<p:inputText id="hiddenValue" value="#{cc.attrs.text}"/>

更新:我需要更正确的定义:能够对我从backing bean传递到composite component内backing component内的composite component的对象进行突变.因此，当我执行process或execute我的composite component时，我会获取更新后的值.

Update: there's more correct definition what do I need: Be able to mutate objects which I pass from the backing bean to the composite component inside a backing component of the composite component. So when I perform process or execute my composite component I get the updated values.

这是我的后援部分:

@FacesComponent("rangeChooser")
public class RangeChooser extends UIInput implements NamingContainer  {
    private String text;
    private Calendar from;
    private Calendar to;

    @Override
    public void encodeBegin(FacesContext context) throws IOException{

        super.encodeBegin(context);
    }


    public String getText() {
        String text = (String)getStateHelper().get(PropertyKeys.text);
        return text;
    }

    public void setText(String text) {
        getStateHelper().put(PropertyKeys.text, text);
    }

    /*
        same getters and setters for Calendar objects, from and to
    */

}

我只是不知道如何继续前进?通常，我需要从<p:inputText id="hiddenValue" value="#{cc.attrs.text}"/>中获取一个值并将其转换为两个Calendars对象from和to. 如果有人可以从这里指向我正确的方向，那就太好了. 我知道我需要使用getAttributes().put(key,value)，但不知道该代码放在何处.在此先感谢您.

I just can't realize how do I move on? In general I need to take a value from <p:inputText id="hiddenValue" value="#{cc.attrs.text}"/> and convert it to two Calendars object from and to. It will be great if somebody can point me toward right direction from here. I know that I need to use getAttributes().put(key,value) but don't know where to put this code. Thank you in advance.

推荐答案

根据您的评论，这就是您所期望的.

Based on your comments this is what you expect.

请注意，即使此实现可行，也从概念上讲是不正确的！

Note that even if this implementation works, it is conceptually incorrect!

您正在将from和to视为输入(不是输入组件，而是输入值)，而将text视为输出.这不是JSF的工作方式！

You are considering from and to as INPUTS (not input components, but input values) and text as OUTPUT. This is not the way JSF is intended to work!

但是，这里是

<cc:interface componentType="rangeComponent">
    <cc:attribute name="from" />
    <cc:attribute name="to" />
    <cc:clientBehavior name="rangeSelected" event="dateSelect" targets="from to"/>
</cc:interface>

<cc:implementation>

    <div id="#{cc.clientId}">
        <p:calendar id="from" value="#{cc.attrs.from}"/>
        <p:calendar id="to" value="#{cc.attrs.to}"/>
    </div>

</cc:implementation>

用于页面:

<h:form>
    <e:inputRange from="#{rangeBean.from}" to="#{rangeBean.to}" text="#{rangeBean.text}">
        <p:ajax event="rangeSelected" process="@namingcontainer" update="@form:output" listener="#{rangeBean.onChange}" />
    </e:inputRange>

    <h:panelGrid id="output" columns="1">
        <h:outputText value="#{rangeBean.from}"/>
        <h:outputText value="#{rangeBean.to}"/>
        <h:outputText value="#{rangeBean.text}"/>
    </h:panelGrid>
</h:form>

具有此支持组件:

@FacesComponent("rangeComponent")
public class RangeComponent extends UINamingContainer
{
    @Override
    public void processUpdates(FacesContext context)
    {
        Objects.requireNonNull(context);

        if(!isRendered())
        {
            return;
        }

        super.processUpdates(context);

        try
        {
            Date from = (Date) getValueExpression("from").getValue(context.getELContext());
            Date to = (Date) getValueExpression("to").getValue(context.getELContext());

            ValueExpression ve = getValueExpression("text");
            if(ve != null)
            {
                ve.setValue(context.getELContext(), from + " - " + to);
            }
        }
        catch(RuntimeException e)
        {
            context.renderResponse();
            throw e;
        }
    }
}

与此后备豆:

@ManagedBean
@ViewScoped
public class RangeBean implements Serializable
{
    private static final long serialVersionUID = 1L;

    private Date from = new Date(1000000000);
    private Date to = new Date(2000000000);
    private String text = "range not set";

    public void onChange(SelectEvent event)
    {
        Messages.addGlobalInfo("[{0}] changed: [{1}]", event.getComponent().getId(), event.getObject());
    }

    // getters/setters
}

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