如何在jsf中基于布尔变量显示两种不同类型的组件? [英] How to display two different types of components based on a boolean variable in jsf?

问题描述

我已经考虑了一段时间-没有一个好主意.

I have thought about this for a while - not getting a good idea.

这是问题所在.我将不得不在文本框中显示文本或将其显示为输出文本.如何在JSF中使用布尔变量来做到这一点?

This is the problem. I will have to display a text either in a text box or as an output text. How do I do this using a boolean variable in JSF?

我不想将h:inputText设为只读/禁用/使其只读，它基于boolean，我想显示一个干净的标签或输出文本.

I do not want to make an h:inputText and disable/make read only, it based on the boolean , I want to display a clean label or an output text.

建议?

推荐答案

使用rendered属性.它需要一个布尔表达式.

Make use of the rendered attribute. It takes a boolean expression.

<h:inputText value="#{bean.input}" rendered="#{bean.editmode}" />
<h:outputText value="#{bean.input}" rendered="#{!bean.editmode}" />

如果表达式的计算结果为true，则组件将在组件树中呈现，并在生成的HTML输出中可见.如果它评估false，它将不会被呈现，因此不会被发送到HTML输出.

If the expression evaluates true, the component will be rendered in the component tree and be visible in the generated HTML output. If it evaluates false, it will not be rendered and thus not be emitted to the HTML output.

还有其他几个示例，您可以使用它们来表达布尔表达式.

Here are several other examples how you could express a boolean expression.

<h:someComponent rendered="#{bean.booleanValue}" />
<h:someComponent rendered="#{bean.intValue > 10}" />
<h:someComponent rendered="#{bean.objectValue == null}" />
<h:someComponent rendered="#{bean.stringValue != 'someValue'}" />
<h:someComponent rendered="#{!empty bean.collectionValue}" />
<h:someComponent rendered="#{!bean.booleanValue && bean.intValue != 0}" />
<h:someComponent rendered="#{bean.stringValue == 'oneValue' || bean.stringValue == 'anotherValue'}" />

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