Topic group

dBASE Plus forms (and the menus and toolbars you create for them) make up the user interface of an application. The forms you design become the windows and dialog boxes of your application. Some of the components you place on a form are the controls that let a user operate the application. Other components are data objects that are invisible when the application runs but that link the application with data in tables.

Components contain three kinds of information:

State information. Information about the present condition of a component is called a property of the component. Properties are named attributes of a component that a user or an application can read or set. Examples of properties are Height and Color.

Action information. Components generally have certain actions they can perform on demand. These actions are defined by methods, which are procedures and functions you call in code to tell the component what to do. Examples of component methods are Move and Refresh.

Feedback information. Components provide opportunities for application developers to attach code to certain occurrences, or events, making components fully interactive. By responding to events, you bring your application to life. Examples of component events are OnClick and OnChange.