Hi Bill,
the rendered attribute is actually checked for more often - at the
beginning of every lifecycle phase. It's very dangerous to make it an
expensive operation - as well as letting it change it s value out of
an action method.
regards,
Martin
On 4/2/06, Bill Schneider <[EMAIL PROTECTED]> wrote:
> Hello,
>
> I just learned there's a subtle but important difference between
> <h:inputHidden value="#{bean.foo}"/> and <t:saveState
> value="#{bean.foo}"/>, assuming bean.foo is a String property.
> inputHidden and saveState look very similar and they have the same end
> result of setting bean.foo, but they get applied at different phases of
> the JSF lifecycle. <t:saveState> is during Restore View phase,
> <h:inputHidden> is during Apply Request Values.
>
> This is an important distinction if you have something like
> <h:commandLink rendered="#{bean.foo}">--I was very confused when my
> commandLink action wasn't executed, yet the link was still displayed.
>
> the other lesson learned is that the 'rendered' attribute is actually
> evaluated twice, once in Restore View to decide whether the
> commandLink/Button you clicked on should actually run the action; and a
> separate time during Render Response to decide whether to show the link
> again.
>
> Hope that sharing this spares others the confusion I had trying to get
> my code to work.
>
> -- Bill
>
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