f:setPropertyActionListener 设置空值而不是预期值

发布于 2024-12-15 22:19:13 字数 872 浏览 2 评论 0原文

我的观点是：

<h:commandLink value="BookFlight" action="#{bookSeatController.doLoginOrCC}">
   <f:setPropertyActionListener target="#{bookSeatController.flightNumber}" 
                  value="#{flightInfoController.flight.number}" />
</h:commandLink>

我的 setter 是：

public void setFlightNumber(String flightNumber) {
   this.flightNumber = flightNumber;
}

当我使用调试器时，我在 setter 中得到 flightNumber 为 null 。但是，如果我将视图更改为以下内容：

<h:commandLink value="BookFlight" action="#{bookSeatController.doLoginOrCC}">
   <f:setPropertyActionListener target="#{bookSeatController.flightNumber}" 
                  value="122334" />
</h:commandLink>

flightNumber 属性设置为 122334。这是如何引起的以及如何解决它以设置预期值而不是 null？

原文

My view is:

<h:commandLink value="BookFlight" action="#{bookSeatController.doLoginOrCC}">
   <f:setPropertyActionListener target="#{bookSeatController.flightNumber}" 
                  value="#{flightInfoController.flight.number}" />
</h:commandLink>

My setter is:

public void setFlightNumber(String flightNumber) {
   this.flightNumber = flightNumber;
}

When I use the debugger I get a flightNumber of null in the setter. However, if I change the view to the following:

<h:commandLink value="BookFlight" action="#{bookSeatController.doLoginOrCC}">
   <f:setPropertyActionListener target="#{bookSeatController.flightNumber}" 
                  value="122334" />
</h:commandLink>

The flightNumber property is set to 122334. How is this caused and how can I solve it to set the intended value instead of null?

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微暖i 2024-12-22 22:19:13

如果 #{flightInfoController.flight.number} 是请求范围的，那么它必须在处理表单提交的请求期间保留完全相同的 flight显示表单的请求。这必须发生在 bean 的（后）构造函数中。

如果这不是一个选项，因为它取决于一些基于请求的变量，那么您最好的选择是将 bean 放在视图范围中（但是我仍然假设您的 bean 设计正确，它不做任何业务/ getter 中的预加载工作）。

如果将 bean 放入视图范围又不是一个选项，那么您需要将其作为完整的请求参数传递。您可以通过来做到这一点。

<h:commandLink value="BookFlight" action="#{bookSeatController.doLoginOrCC}">
   <f:param name="flightNumber" value="#{flightInfoController.flight.number}" />
</h:commandLink>

您可以让 JSF 通过 BookSeatController 中的 @ManagedProperty 或当前视图中的来设置它。

另请参阅：

If the #{flightInfoController.flight.number} is request scoped, then it has to preserve exactly the same flight in during the request of processing the form submit as it was during the request of displaying the form. This has to happen in the bean's (post)constructor.

If that is not an option, because it depends on some request based variables, then your best bet is to put the bean in the view scope instead (I however still assume that your bean is properly designed that it doesn't do any business/preloading job in getters).

If putting the bean in the view scope is in turn not an option, then you'd need to pass it as a fullworthy request parameter instead. You can do that by <f:param>.

<h:commandLink value="BookFlight" action="#{bookSeatController.doLoginOrCC}">
   <f:param name="flightNumber" value="#{flightInfoController.flight.number}" />
</h:commandLink>

You can let JSF set it by @ManagedProperty in the BookSeatController or by <f:viewParam> in the current view.