Tutorial Chapter 3: Displaying Data (Windows/Forms)
This chapter illustrates opening a window that contains a form to
display information to the user. An SQL statement is used to retrieve the data from a database
table. A form specification file is defined to display the values retrieved. The actions that are
available to the user are defined in the source code, tied to buttons that display on the
form.
Application Overview The .4gl File - Opening Windows and Forms OPEN WINDOW instruction, and destroys a window with the CLOSE WINDOW instruction.The .4gl File - Interacting with the User The .4gl File - Retrieving and Displaying Data DISPLAY BY NAME statement.Example: dispcust.4gl (function query_cust) customer table and displays it in a form.The Form Specification File Example: Form Specification File custform.per dispcust.4gl program to display program variables to the user. This form uses a layout with a simple GRID to define the display area.Compiling the Program and Form Compile menu option in the Project view or the fglform tool, an XML file is generated that has a file extension of .42f . The runtime system uses this file along with your programs to define the Abstract User Interface.