PROCESS EVENTS statement

Processes all outstanding events without blocking for user input.

Syntax

PROCESS EVENTS

Example

This procedure counts to 1,000 until you choose STOP:

r-proevs.p

DEFINE VARIABLE ix       AS INTEGER NO-UNDO.
DEFINE VARIABLE stop-sel AS LOGICAL NO-UNDO.

DEFINE BUTTON stop-it LABEL "STOP".

DISPLAY stop-it.

ON CHOOSE OF stop-it
  stop-sel = TRUE.

ENABLE stop-it.

DO ix = 1 TO 1000:  
  DISPLAY ix VIEW-AS TEXT.
  PROCESS EVENTS.
  IF stop-sel THEN LEAVE. 
END.

On each pass through the loop, the procedure displays the new value of ix and then checks whether any events are waiting to be processed. If no events have occurred, execution continues and the loop iterates. If the STOP button has been chosen, that event is processed changing the value of stop-sel. When execution continues, the program exits the loop.

If the loop does not contain the PROCESS EVENTS statement, the choose event never processes and the loop iterates until ix equals 1,000.

Notes

See also

WAIT-FOR statement (ABL only), WAIT-FOR statement (.NET and ABL)