Re: "DoEvents" equivalent in Forms 4.5

On Mon, 05 Jan 1998 14:11:43 GMT, manders_at_mbnet.mb.ca (Michael Anderson) wrote:

>Like YyWong (see "Cancel operation when procedure is running") I have
>the problem where I would like to implement a cancel button that can
>be used while a procedure is running. The problem is I could exit the
>loop if a condition changed, but Forms does not process any events
>until the trigger that is currently running is done. Visual Basic has
>DoEvents which passes control to the operating system, so that events
>such as pressing a cancel button or moving the form can be processed.
>Is there such a command or a way of implementing a similar thing in
>Oracle Forms 4.5?

Several ...
A "simple" is to have a timer event as the communication with the long-lasting procedure. You submit your procedure through the queue-manager (DMBS-JOB) or something simular. I've used Reports 2.5 to submit jobs in batch. Then use DBMS_PIPE to communicate with batch-job.
Unfortunately forms does not support multi-threating - which could solve the problem very easy. Once the MDI is executing a procedure it "hangs" until it's done. I'm not sure - as I havn't had the chance to check it out - but I think this is one of the "problems" solved in Dev/2000 2.0.

Anyway - it's never a good thing to have resource demanding processing running on your client. If you need a job to run for instance for 10 minutes - why not free the client and let the server do the job? Then the user is free to do whatever he/she wants to do - for instance answer the phone and lookup things in other applications - or the same application. This can only be done by usage of batch-like jobs - for instance DBMS_JOB running a storeprocedure - called when the user submits the process. Then to give feedback both on the process but if the user requests cancellation - you use either a simple table or DBMS_PIPE. Regards
Peter H. Larsen (petlars_at_pip.dknet.dk) Oracle Consultant (not affiliated with Oracle) Received on Tue Jan 06 1998 - 00:00:00 CET