HP RPG/XL Programmer's Guide (30318-90001)

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retrieve the form from the VPLUS forms file. The third step is to enter
the VPLUS action, INIT, to place FORMSPEC values in the form fields. The
fourth step is to enter the VPLUS action, SHOMSG, to clear the VPLUS
message window. And the last step is to use the VPLUS action, SHOW, to
display the form with its initial values.
Figure 4-16. Displaying a VPLUS Form
Comments
1 This line initializes the DATALN field in the message window
record with the screen length. This operation is done once,
when the form is first displayed.
2 This line initializes the message window field, ENHANC, with the
character J. J is inverse video, half bright. ENHANC is
initialized once, when the form is first displayed.
3 This line enters the VPLUS action, GETNXT, into the ACTION
output field. GETNXT retrieves the form from the forms file and
places it into the VPLUS buffer.
4 This line performs exception output for the record associated
with EXCPT Group V$ACTN.
5 This line enters the VPLUS action, INIT, into the ACTION output
field. INIT initializes the VPLUS buffer fields with FORMSPEC
values.
6 This line performs exception output for the record associated
with EXCPT Group V$ACTN.
7 This line resets the message array pointer, M, to 3. Assuming
that the third element of the message array is a blank line, the
window is cleared.