Topic group

dBASE Plus lets you create windows that are standard features of the Windows environment:

MDI windows

SDI windows

Modal windows

Modeless windows

The following sections briefly describe these form types.

MDI and SDI applications

You can create windows that conform to the Windows Multiple Document Interface (MDI). MDI is a Windows standard that allows an application to manage multiple windows or multiple views of the same document within the main application window. In dBASE Plus, for example, you can have multiple windows (Command window, Navigator, Table designer, and so on) open at the same time. You can also open the same document (form, table, report) multiple times.

You can also create Single Document Interface (SDI) windows with dBASE Plus. Unlike an MDI window, an SDI window does not contain any child windows.

MDI windows are the most appropriate for data entry forms. Forms that you create with the Form designer are MDI windows by default.

Modal and modeless windows

dBASE Plus lets you create both modal and modeless windows.

A modeless window does not take control of the user interface. A user can switch between modeless windows while an application is running. For example, the various windows that appear in the dBASE Plus Form designer, such as the Control palette, the Field palette, and the Inspector, are modeless windows.

A modal window takes control of the user interface. A user cannot switch to another window without exiting a modal window. A dialog box is an example of a modal window; when it’s open, users cannot take any other actions outside the dialog box until it is closed. Modal forms are most appropriate as dialog boxes in applications.

Customizing the MDI form window

Following are some standard features of MDI windows:

They are moveable and sizeable.

They have a window title, a Control-menu box, Maximize and Minimize buttons.

When active, their menus replace the menus in the application menu bar.

They are bounded by the MDI parent window’s frame.

If the MDI property is set to true, those features are automatically applied to the form. Accordingly, the following form properties are automatically set to true: Minimize, Maximize, Sizeable, Moveable, and SysMenu. Changing the MDI-required properties will have no effect until you change the MDI property itself to false. For more information about any of these properties, press F1 when the property in the Inspector is highlighted.