Interactive instructions

Control application forms with interactive instructions that perform field input and action handling.

These interactive instructions allow the program to respond to user actions and data input. For example the INPUT BY NAME block controls a set of form fields where the user can enter data:
DEFINE cust_rec RECORD LIKE customer.*
INPUT BY NAME cust_rec.*
    ...
    BEFORE FIELD cust_name
        ...
    ON ACTION print
        ...
END INPUT

Interactive instructions can be implemented as modal or parallel dialogs. Modal dialogs control a given window, and that window closes when the dialog is accepted or canceled. The window displays on the top of any existing windows which are not accessible while the modal dialog executes. Parallel dialogs allow access to several windows simultaneously; the user can switch from on window to the other.