Very interesting!!
Two new questions regarding valid EL expressions:
1. How exactly will the syntax and procedure be for using a Facelet
function as rendered condition?
2. Is it possible to obtain elements of Lists at specific positions and
compare them with fixed values.
Ex: rendered="#{mb.myList[0] eq 'element1'}"
Regards,
JV
-----Mensaje original-----
De: Mike Kienenberger [mailto:[EMAIL PROTECTED]
Enviado el: viernes, 28 de julio de 2006 17:36
Para: MyFaces Discussion
Asunto: Re: Rendered propety valid expressions?
Just keep in mind that <, >, & and others are special html characters.
You're better off using and, or, gt, ge, lt, le, eq, ne.
On 7/28/06, Matthias Wessendorf <[EMAIL PROTECTED]> wrote:
> John,
>
> maybe this gif (JSF 1.1) is helpful too
>
> http://autoren.w3l.de/w3lmedia/W3L/Medium036198/ausdruecke.gif
>
> On 7/28/06, Mike Kienenberger <[EMAIL PROTECTED]> wrote:
> > On 7/28/06, John Conner <[EMAIL PROTECTED]> wrote:
> > > I have just started with JSF and have been playing around with el
> > > expressions in the rendered property of components. Is there
someplace
> > > that explains what is valid/invalid as an expression for this
property?
> >
> > The JSF 1.1 spec (JSR-127) under 5.1.2 "Value Binding Expression
> > Syntax", which starts off by saying
> >
> > "The syntax of a value binding expression is identical to the syntax
> > of an expression
> > language expression defined in the JavaServer Pages Specification
(version 2.0),
> > sections 2.3 through 2.9, with the following exceptions..."
> >
> >
> > > Specifically is it possible to:
> > > 1. Use an and condition like
> > > rendered="#{mb.propertyBoolean1 && mb.propertyBoolean2}"
> >
> > Yes, although I'd recommend using "and" instead of "&&" (I don't
> > remember if it's & or && in any case, but this avoids that issue as
> > well as escaping issues).
> >
> >
> > > 2. Is it possible to compare to an enum value
> > > rendered="#{mb.enumValue == a.b.c.EnumClass.ENUM_VALUE}"
> >
> > I don't think so since variables must be managed beans or one of the
> > other predefined values. However, you could write your own resolver
> > that also checked for enumeration classes.
> >
> > > 3. Use a complex call like
> > > rendered="#{mb.someFunction(mb2.value1)}"
> >
> > Only if you're using Facelets or another viewhandler that lets you
> > define functions.
> >
> > For JSF 1.2, everything is the JSP 2.0 unified EL. I think this is
> > also what Facelets uses underneath as an espression language (I have
> > el-api.jar and el-ri.jar files from glassfish to make it work).
> >
> > In any case, everything about the expression language is configurable.
> > A long while back, someone posted a replacement EL that was
> > javascript.
> >
>
>
> --
> Matthias Wessendorf
>
> further stuff:
> blog: http://jroller.com/page/mwessendorf
> mail: mwessendorf-at-gmail-dot-com
>
