The referenced element is undefined

[Timo Nentwig]

Hi!

I'm new to XML schemas; can somebody explain why bar is undefined?

<xs:element name="bar">
<xs:complexType >
<xs:simpleConte nt>
<xs:extension base="xs:string ">
<xs:attribute name="id" type="xs:string " use="required" />
</xs:extension>
</xs:simpleConten t>
</xs:complexType>
</xs:element>

<xs:element name="foo">
<xs:complexType >
<xs:sequence>
<xs:element ref="bar" maxOccurs="unbo unded" />
</xs:sequence>
</xs:complexType>
</xs:element>

[Priscilla Walmsley]

Hi,

It's probably a namespace issue. If your schema has a target namespace,
you need to either

1. Make that namespace the default namespace, as in:

<xs:schema targetNamespace ="xxx" xmlns="xxx" ....

OR

2. Give that namespace a prefix, and use the prefix in the element
reference, as in:

<xs:schema targetNamespace ="xxx" xmlns:pre="xxx"
....

<xs:element ref="pre:bar" maxOccurs="unbo unded"/>
Hope that helps,
Priscilla

-----------------------------------------------------
Priscilla Walmsley
Author, Definitive XML Schema (Prentice Hall PTR)
-----------------------------------------------------

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[Timo Nentwig]

Priscilla Walmsley wrote:

It's probably a namespace issue. If your schema has a target namespace,
you need to either

So the schema (Listing 2) at
http://www-106.ibm.com/developerwork...tml?ca=dnt-520
isn't valid at all?

I actually tried it with an example schema included in the Apache JaxMe
distribution which has this definition:

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xml:lang="EN"
targetNamespace ="http://ws.apache.org/jaxme/examples/misc/address"
elementFormDefa ult="qualified" attributeFormDe fault="unqualif ied">

[Priscilla Walmsley]

> So the schema (Listing 2) at

http://www-106.ibm.com/developerwork...2.html?ca=dnt-
520isn't valid at all?

No, I said "If your schema has a target namespace". That one's fine
because it doesn't have a target namespace.

The second example you gave me:

<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema" xml:lang="EN"
targetNamespace ="http://ws.apache.org/jaxme/examples/misc/address"
elementFormDefa ult="qualified" attributeFormDe fault="unqualif ied">

Using this schema, because it DOES have a target namespace, you DO need
a namespace declaration for the target namespace BUT ONLY IF you are
planning to reference other components (e.g. element ref="xxx:bar").

If you show me your whole schema I can probably explain better...

Priscilla
-----------------------------------------------------
Priscilla Walmsley pr*******@walms ley.com
Author, Definitive XML Schema (Prentice Hall PTR)
-----------------------------------------------------

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[Timo Nentwig]

Priscilla Walmsley wrote:

If you show me your whole schema I can probably explain better...

Got it working thanks. Watch out for another posting of mine :-)