The program manipulates patient record files. These are simple OLE container documents that have no contents except other OLE objects. The user can insert objects by one of two ways. The first way is the usual method of selecting insert object from the menu. The dialog box is a standard system dialog that allows either embedded or linked objects to be added. The second way to insert an object is to query the database. Selecting query from the menu of the main window brings up a dialog box with buttons for queries on identification number or diagnostic information. The dialog also tracks the currently selected patient identification number. Each button brings up a dialog box specific for each query.
The dialog boxes have editable textboxes for the fields of the database. The queries are performed by simple QBE (Query By Example) forms. The buttons at the bottom of the dialog boxes allow the user to perform a query on the database, scroll through the database records in the current view or select the current record. Selecting a record on the Id dialog makes the id of the current record become the currently selected patient identification number on the main dialog. This number will be automatically entered in the text field for id on the Diagnostic Query box. Pushing select on the Diagnostic Query box will embed the file associated with that record into the main view. The button controls, text fields and several invisible controls are all VBX controls. The database communication is performed using the ODBC protocol.
A block diagram of the components of the PC demonstration is shown in figure 11. The program was compiled with Borland C++ 4.51 using vendor and third party libraries, targeted for Windows 3.1/3.11. OCF (Object Component Frameworks) is an object oriented encapsulation of the OLE library. OWL (Object Windows Library) is an object oriented GUI (Graphical User Interface) library for Microsoft Windows. The VBX control interfaces with a local database over a ODBC connection.