Customization > Extensibility Through Profiles, Stereotypes, Tag Definitions and Scripts > Extensibility through stereotype scripts and script items > Extending model item properties through stereotypes and tag definitions > Creating a tag definition to extend model item properties
  
Creating a tag definition to extend model item properties
This topic documents creating a Tag Definition through the Packages pane. For information about using a Profile Diagram to create a Tag Definition, see Creating a tag definition on a profile diagram.
To create a tag definition to extend model item properties:
1. If you have not created a profile Package, create a profile Package. For more information, see Creating a profile Package.
2. Right-click the profile Package in which you want to create the Tag Definition, point to New, point to UML, point to Profiles, and then click Tag Definition.
3. Name the Tag Definition as required.
We recommend that you prefix the name with a prefix that is common to all Tag Definitions used in the Profile.
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The Name has to be unique within the Model; spaces and underscores are ignored when checking the uniqueness of a Tag Definition Name.
You may experience problems if you apply a Tag Definition to an item and the Tag Definition's name matches an automation interface property name of that item.
If you want the display name of the Tag Definition in Modeler to be different from its real name, on the General tab of the Tag Definition's property pages, type a display name in the Name Alias box.
4. Open the Tag Definition's Property Pages, and then click the Type tab.
5. Select the required Data Type, and set the Default Value or Values as appropriate. For more information about the data types, see the related links below.
6. Click the Usage tab, and then set the check boxes as required. For more information about the options, see the related links below.
7. On the Usage tab, click Publish, and then from the confirmation dialog click Yes.
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If you create a Tag Definition through the Items tab of a Stereotype's Property Pages or by right-clicking a Stereotype, pointing to New and then clicking Tag Definition, the Tag Definition will be linked to the Stereotype.
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A Tag Definition cannot be used until it is published. After publishing a Tag Definition, its Data Type cannot be changed.
You typically require database write access permissions to publish a Tag Definition. If a Tag Definition is not linked to any Stereotypes that have model item types defined, you can publish that Tag Definition without database write access permissions; however, having published the Tag Definition, you require database write access permissions to make the Tag Definition usable, that is:
Link the Tag Definition to a Stereotype that has model item types defined.
Define model item types for any linked Stereotypes.