38 Chapter 2: iTool System Architecture
Registering Components iTool Developer’s Guide
Registering Components
Registering an object class links the file containing the IDL code that defines the
object (an iTool, a visualization type, an operation, etc.) with the object identifier.
Objects can be registered either with the iTool system object (in which case their
identifiers are fully qualified) or with an individual iTool class (in which case their
identifiers are relative to the iTool or to a specific container within the tool).
When an object is registered, it is not immediately instantiated. Instead, the
information required to create the object is saved in an object descriptor and placed in
the appropriate location in the iTool hierarchy. Later, when the functionality
contained in the object is needed, the object descriptor either instantiates the object or
provides a reference to an existing instance of the object.
Registration Methods
Objects are registered using the ITREGISTER procedure (to register the object with
the iTool system object) or by calling a Register method on an individual iTool
component object.
Registering Objects with the System Object
Individual iTool components can be registered with the iTool system object. Of these:
• individual iTools must be registered with the system object before they can be
created and displayed.
• visualization types, annotation types, and file readers and writers may be
registered with the system object, but can also be registered with an iTool.
Components that are registered with the system object will be available to all
iTools.
• user interface types must be registered with the system object; however,
creation of new user interfaces is a rare and complex occurrence.
To register an object with the iTool system object, use the ITREGISTER procedure.
See “ITREGISTER” (IDL Reference Guide) for details and “Registering a New Tool
Class” on page 101 for an example using ITREGISTER.
Registering Objects with an iTool
Visualization types, operations, manipulators, file readers, and file writers can be
registered with an individual iTool. Of these, all must be registered with an individual
