With a Parllel.Pipeline, how can you update the UI in the main thread?

[Tim Koscielski 0]

I am just getting familiar with using OmniThread and I have been trying to figure out how to get feedback from a Parallel.Pipeline to the main UI thread to update an activity indicator or progress bar. I understand how to use TOmniEventMonitor when using the CreateTask API call. But as I look at a Parallel.Pipeline command I can't see how to register a TOmniEventMonitor object to collect info from the threads that are part of the Pipeline.

 

What is the best option to get messages back to the UI to update progress for a Parallel.Pipeline task?

 

In looking at the FileScanner demo, the are doing something like this to create the task.

 

FFolderScanner := Parallel.Pipeline
    .NoThrottling
    .Stage(UniqueFilter_asy)
    .Stage(FolderScanner_asy)          
      .NumTasks(inpNumScanners.Value)
    .Stage(DataCollector_asy,          
      Parallel.TaskConfig.OnTerminated(WorkDone)
      )
    .Run;

How do I link in or use a TOmniEventMonitor that can work with each of the Stages of this Pipeline.

 

Thanks.

 

tim

[Tim Koscielski 0]

OK, I think I found that I can use a TOmniMessageQueue as one option. If I create this with a handler for the OnMessage event, that seems to allow me to accomplish updating the Activity Indicator in the UI without adding much overhead to the Parallel.Pipeline process.

 

Is this a good option for the library or is there another method that perhaps works better?

 

[Lars Fosdal 1792]

Using a queue is a healthy principle.