An attribute group definition is an association between a name
and a set of attribute declarations, enabling re-use of the same set in several
complex type definitions. Named groups of attribute declarations can greatly
facilitate the maintenance and reuse of common attribute declarations in an
XML schema.
The following instructions were written for the Resource perspective,
but they will also work in many other perspectives.
To add an
attribute group to an XML schema, follow these steps:
- Open your XML schema in the XML schema editor.
- In the Outline view, right-click the XML schema and click Add
Attribute Group. It appears in the Attribute
Groups folder.
- Select your new group, and in the Properties view, type a name
for the attribute group in the Name field.
- To add an attribute, right-click your attribute group in the Outline
view, click Add Attribute. The attribute
appears below the attribute group in the Outline view.
- Select the attribute, and in the Properties view, type the Name of
it.
- Click the More button and specify the
type for the attribute. To specify that an attribute's type is
anonymous, when the User-defined simple type radio
button is selected, click **anonymous** in the type
list. The anonymous type is added to the outline under the attribute.
Expand the attribute to see it. You can then start adding content to the new
anonymous type.
- An attribute reference provides a reference to a global attribute.
To add an attribute reference, right-click your attribute group, and click Add
Attribute Ref. A declaration that references a global
attribute enables the referenced attribute to appear in the instance document
in the context of the referencing declaration. The menu option to add
an attribute reference only appears if there are global attributes defined
elsewhere in the document.
- Select the reference (which appears below the attribute group
in the Outline view), then select the global attribute you want it to reference
from the ref drop down list.
- An attribute group reference provides a reference to an attribute
group. To add an attribute group reference, right-click your attribute group,
and click Add Attribute Group Ref, and fill in the
field values as necessary. A declaration that references an attribute
group enables the referenced attribute group to appear in the instance document
in the context of the referencing declaration. The menu option to add an attribute
group reference only appears if there are attribute groups defined elsewhere
in the document.
- Select the reference (which appears below the attribute group
in the Outline view), then select the attribute group you want it to reference
from the ref drop down list.
- An any element enables attributes to appear
in any elements. To add an any attribute,
right-click in your attribute group and click Add Any Attribute. The any appears below the attribute group in the Outline
view. You can specify the following values for an any attribute:
- For a namespace value, you can select ##any (this allows
any well-formed XML from any namespace), ##local (this allows any
well-formed XML that is not declared to be in a namespace, ##other (this
allows any well-formed XML that is not from the target namespace of the type
being defined) or ##targetNamespace (which is shorthand for the target
namespace of the type being defined).
- For a processContents value, you can select skip (the
XML processor will not validate the attribute content at all), lax (the
XML processor will validate the attribute content as much as it can), or strict (the
XML processor will validate all the attribute content).
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