ON TIMER block
The ON TIMER seconds
clause defines a set of instructions that
must be executed at regular intervals. This interaction block can be used, for example,
to check if a message has arrived in a queue, and needs to be processed.
Do not mix ON TIMER
and ON
IDLE
clauses.
As ON TIMER
can fire field input validation, it is therefore not
recommended in dialogs allowing input.
The parameter of ON TIMER
must be an integer literal or variable.
If the value is zero, the dialog timeout is disabled.
ON TIMER
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 reasonable period of time, such as 10, 20 or 60
seconds.ON TIMER 30
CALL check_for_messages()
The timer value is taken into account when the dialog initializes its internal data structures. If you use a program variable instead of an integer constant, a change of the variable has no effect if the change takes place after the dialog has initialized. If you want to change the value of the timeout variable, it must be done before the dialog block.