Developer’s Guide

Chapter 7
Developing third-party FileMaker plug-ins
If you are a C or C++ programmer and familiar with advanced
calculations in FileMaker
Pro and FileMaker Developer, you can
create external function plug-ins that extend the feature set of the
applications. The plug-ins can take advantage of recursion and
looping or hook into other programming interfaces. Users can enable
your plug-ins in FileMaker
Pro, FileMaker Developer, and
FileMaker Server and use your external functions in their calculation
fields and scripts.
Plug-ins must be registered with FileMaker. The FileMaker web site
(www.filemaker.com) includes a plug-in registration form and a
database of all the registered plug-ins. You can browse this database
to get an idea of what kind of plug-ins already exist and use it to list
your own plug-ins. For more information, see
“Registering your
plug-in” on page 68.
About external functions
The FileMaker Developer CD includes an example plug-in project
that you can modify to include your own external functions. Users
can access your plug-ins through the Specify Calculation dialog box.
Follow these general steps to prepare your custom plug-ins:
1. Edit the example plug-in files to add your custom programming
code.
2. Compile and test the customized plug-in.
3. Register your plug-in with FileMaker.
4. Install the compiled plug-in file for your users.
To access your external functions, your users:
1. Enable your plug-in through the Preferences dialog box.
2. Configure your plug-in, if required.
3. Define or edit a calculation field.
4. In the Specify Calculation dialog box, choose
Function_Name(parameter 1 ...) as the calculation formula.
To see all external functions, select External functions from the View
drop-down list.
About the example plug-in
The example plug-in project is designed to illustrate what a complete
plug-in looks like. You can compile the example project files to
create a plug-in with several external functions that users can access
through the Specify Calculation dialog box. You can examine and
modify the source code of the example files in any text editor.
The plug-in example includes seven external functions. See
“Description of the FMExample plug-in’s external functions” on
page 61.
The plug-in example files include all the source code required to
compile the plug-in for the Windows and Mac
OS X platforms. In
addition to the plug-in source code, FileMaker Developer includes
project files for CodeWarrior Development Studio, Mac OS X
Edition 8.3, and Microsoft Visual Studio .NET 2002.
The example plug-in files are located in the
English Extras\Examples\FMExample folder on the FileMaker
Developer CD. The plug-in example source code files are located in
subfolders in the FMExample plug-in folder. The following tables
describe some of the folders and files.