Using POE is not something you do for just one thing, it affects the whole
way you would code your app, so you would use POE to do non-blocking file
transfer (using something like POE::Component::Client::FTP), and use POE to
do non-blocking DBI updates (using something like
POE::Component::SimpleDBI). It doesn't really work to use POE for just one
thing in your app -- to take advantage of POE, you either embrace it for
everything or don't use it at all. YMMV.
On 2/10/08, Octavian Rasnita <[EMAIL PROTECTED]> wrote:
>
> Hi Mark,
>
> Thank you for your help and for some clarifications.
> I didn't know that cooperative multitasking doesn't imply multithreading.
>
> But in this case I am not sure that POE can help me to do what I want. The
> ProgressDialog is not responsive not because updating the progress bar takes
> much processor time, but because the file download and database updates does
> that.
>
> If POE can't do the file upload and the database update in a separate
> thread but in the main thread, the one that manages the GUI, then the GUI
> will be unresponsive.
>
> The file upload and database update are continuous tasks, and I cannot put
> a subroutine to do something from 5 to 5 seconds in order to do the file
> download, and now I do something like:
>
> <create the ProgressDialog window>
>
> <while downloading the file>
> <save the current buffer to the hard disk>
> <update the ProgressDialog window>
> <end the file download>
>
> <close the ProgressDialog window>
>
> Well, with POE I can update the ProgressDialog separately, but until the
> file finishes to download, the current window of the program will be
> unresponsive.
>
> With Win32::GUI I can insert the following line in the loop, and then the
> GUI will be much responsive, but I don't know if there is such a thing in
> WxPerl:
>
> Win32::GUI::DoEvents() >= 0 or die "Window was closed during processing";
>
> Do you know by chance if there is a method that makes WxPerl to handle the
> events in the queue before passing to the next step in the loop?
>
> Thank you.
>
> Octavian
>
> ----- Original Message -----
> *From:* Mike Schroeder <[EMAIL PROTECTED]>
> *To:* Octavian Rasnita <[EMAIL PROTECTED]>
> *Sent:* Saturday, February 09, 2008 9:00 PM
> *Subject:* Re: using a progress bar with POE::Loop::Wx
>
> First, with POE, I don't think this would be another thread. POE uses
> cooperative multi-tasking, not threads.
>
> We use two different approaches -- polling a remote job for its progress,
> and reacting to local events.
>
> In our case, we made a Panel that holds the Gauge and some StaticText
> controls to display extra info.
>
> The Panel in turn has a "StartPolling" method which starts off a POE event
> to fetch remote job data, and calls itself again every 5 seconds until the
> job is complete. Here is some stripped down psuedo code:
>
> sub StartPolling {
> # Gather Args
> # Start a POE event to GetData (results will go to ReceiveData)
> # delay_set('StartPolling', 5);
> }
>
>
> Depending on how abstracted your environment is, you may have POE stuff in
> here or not. In our case, we don't.
>
> The Panel also has a "ReceiveData" method which either receives the data
> from the polling events, *or* can receive data directly from a local event.
> Here is some code again -- hopefully it makes sense :)
>
> sub ReceiveData {
> my ( $self, $data ) = @_;
>
> Wx::LogVerbose("Progress ReceiveData: $self " . Dumper $data );
>
> unless ( $self->{_first_data} ) {
> $self->{progress_gauge}->SetRange( $data->{expected} );
> $self->{_first_data} = 1;
> }
>
> if ( $data->{status} eq 'C' ) {
> Wx::LogVerbose("Job $data->{job_id} is Complete");
> # job is done
> $self->_update_data( $data );
> if ( ref $self->{_on_complete} eq 'CODE' ) {
> &{ $self->{_on_complete} } (
> DATA => $data,
> CONTROL => $self,
> FRAME => $self->GetTopLevelParent()
> );
> }
>
> if ( $self->{_close_on_complete} ) {
> $self->GetTopLevelParent()->Close();
> } else {
> # stop polling - happens automatically when frame closed
> $self->GetTopLevelParent()->unregister_control(
> cachekey => $self->{_cache_key},
> control => $self );
> }
> } elsif ( $data->{status} eq 'R' ) {
> Wx::LogVerbose("Job $data->{job_id} is Running");
> # job is running
> $self->_update_data( $data );
> } else {
> Wx::LogVerbose("Unknown Job Status!!! " . Dumper $data);
> }
> }
>
> sub _update_data {
> my ( $self, $data ) = @_;
>
> # Update gauge
> $self->{progress_gauge}->SetValue( $data->{current_count} );
>
> # Update Labels
> $self->{progress_title}->SetLabel( "Job " . $data->{job_id} . ' - ' .
> $data->{description} );
> $self->{expected}->SetLabel( $data->{expected} );
> $self->{current}->SetLabel( $data->{current_count} );
> $self->{remaining}->SetLabel( $data->{current_rate} . ' per ' .
> $data->{rate_unit} );
> $self->{start_time}->SetLabel( $data->{start_time} );
> $self->{eta}->SetLabel( $data->{eta_time} );
> $self->{elapsed}->SetLabel( $data->{duration} );
>
> }
>
> So every time your file download receives another chunk, it should send an
> event over to ReceiveData, which will _update_data() the Gauge and
> StaticText controls.
>
> Hopefully this at least gives you some ideas...
>
> Mike.
>
>
> On 2/9/08, Octavian Rasnita <[EMAIL PROTECTED]> wrote:
> >
> > Hi,
> >
> > I want to use a ProgressDialog to show the progress of a file download
> > and
> > database update.
> > The progress works well, however the ProgressDialog window is very
> > unresponsive because the program uses a single thread.
> >
> > Is it possible to use POE::Loop::Wx for making the dialog window more
> > responsive?
> > Or is there another better method for doing this?
> >
> > In the POE::Loop::Wx examples I've seen that it can be used for making
> > asynchronious requests, but those requests were made automaticly, after
> > a
> > certain number of seconds which were defined in the POE::Session. The
> > requests that were made at a certain command (a button click) were made
> > in
> > the main thread of the program.
> >
> > I need to run the subroutine that does the ProgressDialog update with
> > some
> > parameters and only after a certain part of the file was downloaded or a
> > certain number of records were inserted in the database.
> >
> > Please tell me if I can find an example of using a progress bar that
> > uses a
> > separate thread for doing this.
> >
> > Or if it is better to use the main thread for update the ProgressDialog
> > and
> > a second thread for doing the file download and database update, please
> > give
> > me some hints about how to do that with POE::Loop::Wx or another method
> > that
> > can allow the 2 threads to communicate.
> >
> > Thank you.
> >
> > Octavian
> >
> >
>
>
> --
> Mike Schroeder
> [EMAIL PROTECTED]
> 877-751-3300 x401
>
>
--
Mike Schroeder
[EMAIL PROTECTED]
877-751-3300 x401
