ActiveField is a name for object-oriented Application Programming Interface (API) to QuickField FEA model. Object model consists of objects corresponding to QuickField user interface entities: documents, windows, geometric shapes, data labels, XY-Plots and so on. Complete description of QuickField API objects, their methods and properties is available at http://active.quickfield.com.
There are many tools for application development on Windows® platform. Whether you use Delphi, or Visual C++, Java or any type of Visual Basic - all of them support Automation. Further details about Automation programming techniques could be found in the documentation on specific programming tool.
Video: Programming with QuickField.
Overview of QuickField object model shown as a hierarchy chart: