A global element is an element with a global scope. It is one that has
been declared as part of the main schema rather than as part of a content
model.
The following instructions were written
for the Resource perspective, but they will also work in many other
perspectives.
To add a global
element, follow these steps:
- Open your XML schema in the XML schema editor.
- In the Outline view, select your schema. The entire
schema and its contents should be displayed in the Graph view.
- In the Graph view, right click in the Elements section and
click Add Element.
- In the Properties view, click the General tab,
and type a new name for the global element in the Name field.
- Specify its type information by clicking the More button
and selecting the appropriate type. The Set Type dialog lists all
built-in and user-defined types currently available. You can change the Scope of
the list by selecting one of the following options:- Workspace. Lists all of the types available in
your workspace.
- Enclosing Project. Lists all of the types available
in the project that contains your file.
- (Default) Current Resource. List all of the types
available in your current file.
-
(Optional) Click the
Other tab. In
this page, you can specify the following various values for the global
element:
- abstract. Click true
if you want the global element to be abstract. When a global
element is declared to be abstract, it cannot be used in an instance
document. Instead, a member of that global element's substitution group
must appear in the instance document.
- block. This field determines
whether the global element may be replaced by an element derived from
it.
- final. This field determines
whether this global element may be derived from.
- fixed/default. Click the
More button
and
select the Fixed or
Default radio button and specify an
appropriate value. If you select Fixed, the global
element has a fixed value, which cannot be changed. If you select
Default, the element has a default value.
- form. Use this field to
indicate if the appearance of this global element in an instance of the
XML schema (that is, an XML file associated with the XML schema) must be
qualified by a namespace.
- nillable. Select true
if you do not want the global element to be able to have any child
elements, only attributes.
- substitutionGroup. A
substitution group allows elements to be substituted for other elements.
- Click the Attributes tab. You
can use this page to add attributes, attribute references, attributes group
references, and any attributes to your global element.
- An attribute associates an attribute name with a specific type
and value. To add an attribute, right-click in the Attributes page, and click Add
Attribute. You can specify the following values for
an attribute
- fixed/default. Click the More button
and select the Fixed or Default radio
button and specify an appropriate value. If you select Fixed, the attribute
has a fixed value, which cannot be changed. If you select Default,
the attribute has a default value.
- form. Use this field to indicate if the appearance
of this attribute in an instance of the XML schema must be qualified by a
namespace.
- name. Enter the name of the attribute.
- type. Click the More button
and select the type of the attribute.
- use. This field indicates how an attribute
may be used in an instance document. If you select optional, the attribute
may appear once, but it does not have to. If you select required, the
attribute must appear once. If you select prohibited, the attribute
must not appear. Note: If you selected the Default radio
button, you must select optional in this field, otherwise the default
value will not be valid.
- An attribute reference provides a reference to a global attribute.
To add an attribute reference, right-click in the Attributes page, 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, 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 in the Attributes
page, and click Add Attribute Group Ref. 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, then select the attribute group you want
it to reference from the ref drop down list.
- An any element enables element content according
to namespaces, and the corresponding any attribute element
enables attributes to appear in elements. To add an any attribute,
right-click in the Attributes page and click Add Any Attribute. 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).
- Click the Documentation tab if you want
to provide any information about this global element. The Documentation page
is used for human readable material, such as a description, and the App
Info page can be used to provide information for applications.
You can add a content model to a global element, which is the representation
of any data that may be contained inside the global element. For more information
about working with content models, refer to the related tasks.