ArcGIS Engine Developer Guide

DEVELOPING WITH A RCOBJECTS
The Customize dialog box in ArcMap and
ArcCatalog
The Component Category Manager
Now that you’ve seen two uses of component categories, you will see how to get
your classes registered into the correct component category. Development environments
have various levels of support for component categories; ESRI provides
two ways of adding classes to a component category. The first can only be
used for commands and command bars that are added to either ArcMap or
ArcCatalog. Using the Add From File button on the Customize dialog box
(shown on the left), it is possible to choose a server. All classes in that server are
then added to either the ESRI Gx Commands or the ESRI Mx Commands,
depending on the application being customized. Although this utility is useful, it
is limited since it adds all the classes found in the server. It is not possible to
remove classes, and it only supports two of the many component categories
implemented within ArcObjects.
Distributed with ArcGIS applications is a utility application called the Component
Category Manager, shown on the left. This small application allows you to
add and remove classes from any of the component categories on your system,
not just ArcObjects categories. Expanding a category displays a list of classes in
the category. You can then use the Add Object button to display a checklist of all
the classes found in the server. You check the required classes, and these checked
classes are then added to the category.
Using these ESRI tools is not the only method of interacting with component
categories. During the installation of the server on the target user’s machine, it is
possible to add the relevant information to the registry using a registry script.
Below is one such script. The first line tells Windows for which version of
regedit this script is intended. The last line, starting with “[HKEY_LOCAL_”,
executes the registry command; all the other lines are comments in the file.
REGEDIT4
; This Registry Script enters coclasses into their appropriate Component
Category
; Use this script during installation of the components
; Coclass: Exporter.ExportingExtension
; CLSID: {E233797D-020B-4AD4-935C-F659EB237065}
; Component Category: ESRI Mx Extensions
[HKEY_LOCAL_MACHINE\SOFTWARE\Classes\CLSID\{E233797D-020B-4AD4-935C-
F659EB237065}\Implemented Categories\{B56A7C45-83D4-11D2-A2E9-080009B6F22B}]
The last line in the code above is one continuous line in the script.
The last method is for the self-registration code of the server to add the relevant
classes within the server to the appropriate categories. Not all development
environments allow this to be set up. Visual Basic has no support for component
categories, although there is an add-in that allows this functionality. See the
sections on Visual Basic developer add-ins and Active Template Library (ATL) in
the ArcGIS Developer Help.
78 • ArcGIS Engine Developer Guide