Code in OLE Control Events within PowerBuilder not executing

[#1]

Hi All,

I’m using PB 12.5 Build 2511 on Windows 10.

I've been using SocketTools' File Transfer Control 8.0 since a long time ago and have been using its ActiveX control with PB with no problems until now. Well, sort of because now I'm trying to do something new.

The way I normally use the control in PB is by declaring an OLEObject variable and calling the pertinent methods from the object. Here is a code example of how I use it and works ok (I excluded error handling):

OleObject lole_ftp

lole_ftp = create OleObject

lole_ftp.ConnectToNewObject("SocketTools.FileTransfer.8")

lole_ftp.Initialize('<product key>')
lole_ftp.ServerName = ‘…’

lole_ftp.ServerPort = 21

lole_ftp.UserName = ‘…’

lole_ftp.Password = ‘…’

lole_ftp.TimeOut = 30

lole_ftp.Options = 1

lole_ftp.Connect()

lole_ftp.GetFile('c:\somefile.zip', 'somefile.zip')

lole_ftp.Disconnect()

lole_ftp.Reset()

Destroy lole_ftp

All this works perfectly, but the thing is, now I want to access the ActiveX control events so I can write some script and show a progress bar of the copy process. I understand I cannot do this by using the current method so I read PB's documentation and learned that I have to create an OLE control inside a Window so that the control events get exposed. I did this and now I can see the OnProgress event which according to the manufacturer’s documentation gets fired once a second or so.

So I inserted a line of code to update a progress static text (see image) but the code in the event doesn’t gets executed even though the file gets copied. It could be a fault in the ActiveX control but I seriously doubt it because the control has been in the market for many years and it even includes code examples for doing this using Visual Basic 6 and C++. PowerBuilder is mentioned as a language that can use the control but there are no examples using it for this case.

Any help would be greatly appreciated.

Ricardo

[Former Member]

Hello Ricardo,

I noticed that it looks like you also coded onTaskBegin, onTaskEnd and onTaskRun. Do those events get fired as you would expect?

How big is your file, could it be that it takes less than 1 sec to transfer and therefore never fires the onProgress?

[Former Member]

Christopher,

Those events are triggered when using AsynGetFile() instead of GetFile(). This command downloads the file asynchronously on the background and triggers those events. I tried it but it didn't work either.

My test file is about 20MB and I put it in a hosted FTP server to test the process. In my environment it takes several minutes to download. Precisely that's why I want to show a progress bar to the user.

I inquired SocketTools about this and this is what they responded:

Q: I need to know what windows event id the OnProgress event is triggering. I use PowerBuilder and could successfully insert an OLE object inside a window using your FTP ActiveX control but when I try to add code to be executed by the exposed OnProgress event within PowerBuilder nothing happens. It's like the event is not triggering although the file gets downloaded from the FTP server. I'm using the Getfile() method to download the file.

A: The event ID for OnProgress is 9, but the actual Windows message ID isn't something that's directly exposed by COM (and not something PowerBuilder should need). Whenever you define the event handler, PowerBuilder should create an event sink using the ISinkEvents interface, then obtain the IConnectionPoint interface from our component and use the Advise method to register itself with the control. When that's done, the PowerBuilder application is notified whenever an event is raised. Generally speaking, this should all be handled transparently for you by PowerBuilder.

I don't have much experience with event id's so any help will be greatly appreciated.

Ricardo

p.s. One of my colleagues suggested that the download process might be running in a separate thread and that that might be the reason the work thread is not seeing the events from the worker thread. But this is just mere speculation.

[Former Member]

Hello Ricardo,

I assume you've set a break in onProgress to verify that it gets there?  Was just thinking that if any parameter was null, it would look like the event didn't fire, because st_progress.Text would end up null.  Just clearing the obvious out of the way.

I've seen this before, many, many, many moons ago, but having trouble remembering how I resolved it.

[Former Member]

Christopher,

That's a good point. I thought about it before and removed the code and inserted a new one without the variables. The result was the same.

Inserting a break point doesn't make any difference either.

Ricardo

[Former Member]

Hello Ricardo, Did you get this resolved?

[Former Member]

Christopher,

No I didn't. The last mail exchange I had with the control manufacturer was this:

Q: Is there any way I can trace this lack of connection between PowerBuilder and your control? As I mentioned before everything works fine except the events interface. Maybe I could try a different way in which I would assemble the event interface myself directly in a standard user object inherited from the oleobject.

A: I'm not aware of any way to do this directly. Event sinks are part of the COM API, so theoretically it would be possible but I imagine a fairly complex thing to try and do. This is really something that is the domain of the language or development tool to handle itself, since it has to "wire" the COM event notifications into whatever mechanism it uses for events.

I'm not in a hurry to implement this, though it would be nice to show the progress of the download to the user specially when large files are involved or there is a slow connection.

I guess I'll implement something like Roland Smith's Top Wiz FTP Client where the file is manually handled and sent in parts so I can update a progress bar inside the loop.

Ricardo