Android Question Wait For - sender filter does not work in all circumstances

[JackKirk]

This works:

        'Download new control file
    Obj_FTPClient.DownloadFile("X\" & wrk_phn_imei & ".txt", False, File.DirInternal, "scenes2_control.txt")
  
    'Wait for download to complete...
    Wait For Event_obj_ftpclient_DownloadCompleted(ServerPath As String, Download_success As Boolean)

but this does not:

        'Download new control file
    Obj_FTPClient.DownloadFile("X\" & wrk_phn_imei & ".txt", False, File.DirInternal, "scenes2_control.txt")
  
    'Wait for download to complete...
    Wait For (Obj_FTPClient) Event_obj_ftpclient_DownloadCompleted(ServerPath As String, Download_success As Boolean)

Obj_FTPClient is declared as:

Private Obj_FTPClient As FTP

in Process_Globals.

Anyone have any clues?

 

[Ed Brown]

Are you attempting to download more than a single file at a time? If yes, then you will need to create a new instance of the FTP object for each download.

 

[JackKirk]

Ed, thanks for your response.

No, I'm doing a single download/upload at a time.

I think the weirdo I have discovered is something to do with the Obj_FTPClient having to be global but would like it confirmed - and explained if possible.

 

[Erel]

The DownloadCompleted event doesn't set the Sender object so you cannot add the sender filter parameter. The Net library will be updated in the future.

 

[JackKirk]

Erel,

I spent several hours banging at this.

For everyone's information it would be good to know what other current anomalies there are with using the sender filter parameter.

PS: I am in love with wait for...

PPS: I updated the thread title to be more relevant to others.

 

[Erel]

anomalies there are with using the sender filter parameter

It is not really related to sender filter. It is related to the Net library not setting the Sender itself when raising the event. As I wrote it will be fixed (the methods will return an object that you can use as the sender filter).

 

[JackKirk]

OK, I'll rephrase: in what other circumstances can't the sender filter be used.

I'm not being a PITA, wait for is a great feature that shouldn't be clouded by issues like this.

 

[Erel]

I'm not familiar with any other library that raises an event without setting the sender parameter. It doesn't mean that there aren't. In the past the sender parameter was less important in some cases.

If you have any doubt then:

- Use Wait For without the sender filter parameter. The sender filter is only important when there are multiple objects that raise the same event.
- Or check it yourself by handling the event and testing the output of Log(Sender) to see whether the sender is set or not.

 

[JackKirk]

I'm not familiar with any other library that raises an event without setting the sender parameter

Trust me to tread on the only broken glass on the beach...