ON IDLE block
The ON IDLE seconds
clause defines a set of instructions that
must be executed after a given period of user inactivity. This interaction block can be
used, for example, to quit the dialog after the user has not interacted with the program
for a specified period of time.
Do not mix ON TIMER
and
ON IDLE
clauses.
If the UNBUFFERED
option is used in an input dialog, ON IDLE
and ON TIMER
will flush and validate the
current field content. If the field contains invalid data, an error message is displayed, and the
corresponding code block is not executed. Therefore, ON IDLE
and ON
TIMER
are not recommended in input dialogs using the UNBUFFERED
option.
When implementing multiple dialogs with DIALOG
block, do not mix several
ON IDLE
clauses in different sub-dialog blocks: specify a unique ON
IDLE
clause at the DIALOG
block level.
The parameter of ON IDLE
must be an integer literal or variable. If the
value is zero, the dialog timeout is disabled.
ON IDLE
trigger with a short timeout
period such as 1 or 2 seconds; The purpose of this trigger is to give the control back to the
program after a relatively long period of inactivity (10, 30 or 60 seconds). This is typically
the case when the end user leaves the workstation, or gets a phone call. The program can then
execute some code before the user gets the control back.ON IDLE 30
IF ask_question(
"Do you want to reload information from the database?") THEN
-- Fetch data back from the db server
END IF
The timeout value is taken into account when the dialog initializes its internal data structures. If you use a program variable instead of an integer constant, any change of the variable will have no effect if the variable is changed after the dialog has initialized. If you want to change the value of the timeout variable, it must be done before the dialog block.