如何将参数化的MessageFormat与JSF组件的非Value属性一起使用 [英] How to use Parameterized MessageFormat with non-Value attributes of JSF components

问题描述

我有一个用例，其中我必须使用资源包在UI上显示各种文本.其中一些资源束条目采用参数(例如{0})，因为这些参数我使用h:outputFormat，但有时还不够.

I have use case in which I have to use resource bundle to display various texts on UI. Some of these resource bundle entries take paramets (e.g. {0}), for these I use h:outputFormat but sometimes that isn't enough.

例如

someMessage=Display this message with param {0}

在资源束中.

通常在xhtml上显示它:

To display it on xhtml I normally do:

<h:outputFormat value="#{msg['someMessage']}"><f:param value="#{someBean.value}"/></h:outputFormat>

在简单情况下，效果很好，但对于更复杂的用例而言，还不够.例如，如果我希望commandLink的'title'属性使用上面的资源束条目:

That works well when it's a simple case, but for more complex use cases it isn't enough. For example if I want the 'title' attribute of a commandLink to use the above resource bundle entry:

    <h:commandLink action="logout" title="#{msg['someMessage']}">
        <f:param value="#{someBean.value}" />
        <h:graphicImage library="images" name="image.png" />
    </h:commandLink>

不起作用.我也尝试过:

which doesn't work. I also tried:

    <h:commandLink action="logout">
        <f:attribute name="title">
            <h:outputFormat value="#{msg['someMessage']}"><f:param value="#{someBean.value}"/></h:outputFormat>
        </f:attribute>
        <h:graphicImage library="images" name="image.png" />
    </h:commandLink>

由于f:attibute不允许孩子，这也不起作用.

which also doesn't work since f:attibute doesn't allow children.

即使有黑客可以绕过此操作(例如，使用Primefaces中的悬停组件)，也有其他字段可能需要参数化消息.

Even if there is a hack to bypass this (e.g. using hover component from primefaces) there are other fields that might require a parameterized message.

是否有人知道使用MessageFormat的方法，该方法在JSF组件的非值字段中接受参数?

Does anyone know of a way to use MessageFormat that takes an argument in a non-value field of a JSF component?

推荐答案

您可以创建

You could create a custom EL function for this with which you can ultimately end up like:

<h:commandLink ... title="#{my:format(msg['someMessage'], someBean.value)}" />

您可以使用 MessageFormat 执行作业的API，与<h:outputFormat>在幕后所做的完全一样.

You can use the MessageFormat API to perform the job, exactly as <h:outputFormat> is doing under the covers.

一种替代方法是创建一个自定义组件，该组件的功能与JSTL的良好功能相同'ol

An alternative is to create a custom component which does the same as JSTL's good 'ol <fmt:message> which supports a var attribute to export the formatted message into the EL scope.

<my:outputFormat ... var="linkTitle">
    ...
</my:outputFormat>
<h:commandLink ... title="#{linkTitle}" />

---

更新:JSF实用程序库 OmniFaces 具有

---

Update: JSF utility library OmniFaces has #{of:formatX()} functions and a <o:outputFormat> component for the very purpose.

这篇关于如何将参数化的MessageFormat与JSF组件的非Value属性一起使用的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！