Martin,
I think the goal is to simplify page code when you have conditional rendering.
I know that I have areas on my page that look like this:
<component rendered="#{value eq a}">
<component rendered="#{value eq b}">
<component rendered="#{value eq c}">
<component rendered="#{value eq d}">
<component rendered="#{value ne a and value ne b and value ne c and
value ne d}">
And rarely is the conditional as easy as what you see above, so it
becomes very difficult to read and maintain.
On 6/15/07, Martin Marinschek <[EMAIL PROTECTED]> wrote:
Hi Andrew,
so this does the same as c:choose (sorry for my ignorance, but I don't
know the JSTL too well)?
Can you give us an example where this is useful in the wild?
regards,
Martin
On 6/15/07, Andrew Robinson <[EMAIL PROTECTED]> wrote:
> I am working on the code for a very simple component, but wanted to
> see if there is feedback before finishing it up.
>
> The component is inspired by the JSTL choose but is geared for JSF and
> is more robust. I thought this would be helpful when a lot of facelets
> developers complain about the facelets implementation of choose due to
> render vs. compile time evaluation.
>
> <s:choose type="string" value="object" />
>
> type := index|count (default: count)
> value := (type == index): list of numbers that correspond to children
> indexes (negatives allowed). Default: render all
> (type == count): integer representing max number of components to
> render. Default: render first
>
> Examples:
> <s:choose>
> <h:outputText rendered="false" value="a" />
> <h:outputText value="b" />
> <h:outputText value="c" />
> </s:choose>
> Renders: b
>
> <s:choose value="2">
> <h:outputText rendered="false" value="a" />
> <h:outputText value="b" />
> <h:outputText value="c" />
> <h:outputText value="d" />
> </s:choose>
> Renders: b c
>
> <s:choose value="5">
> <h:outputText rendered="false" value="a" />
> <h:outputText value="b" />
> <h:outputText value="c" />
> <h:outputText value="d" />
> </s:choose>
> Renders: b c d
>
> <s:choose type="index" value="0,-1">
> <h:outputText value="a" />
> <h:outputText value="b" />
> <h:outputText value="c" />
> <h:outputText value="d" />
> </s:choose>
> Renders: a d
>
> <s:choose type="index" value="0,-1">
> <h:outputText value="a" />
> <h:outputText value="b" />
> <h:outputText value="c" />
> <h:outputText value="d" />
> </s:choose>
> Renders: a d
>
> <s:choose type="index" value="5">
> <h:outputText value="a" />
> <h:outputText value="b" />
> <h:outputText value="c" />
> <h:outputText value="d" />
> </s:choose>
> Throws index out of bounds exception
>
> If index, value can be tied to one of:
> Collection of Number or Object
> int[]
> Object[] of Number or Object
> String or Object (comma-separated toString())
>
> If Object and not a Number, Integer.parseInt(obj.toString()) is used.
>
> The default setting is really the most useful (type=count, value=1),
> which is simply render only the first child component that
> isRendered() returns true.
>
>
> Any feedback?
> -Andrew
>
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