Android Question [Solved] Problem with AsyncStreams in prefix mode.

[JoanRPM]

Hello.
In a project I use android as TCP Client and VB6 as TCP Server.
I use the AStreams in prefix mode to send pictures to the Client (Android).
The problem is that, once connected, can only send/receive one transmission (one picture). To send another picture, I need to stop and connect again the Socket.
The bytes transmited by the server are always the same, and in VB6 I include the correct prefix. So the Android Client only receive the first transmission.
In the example, you can click either in the server or in the client, to display one of the two pictures.

In the attached files there are a B4A source and a PC Server executable program.

Anyone know what could be the problem?

Greetings.

 

[Erel]

AsyncStreams in prefix mode works properly. It was tested in many different scenarios.
The problem is most probably in your VB6 code.

You can try the B4J examples that use AsyncStream:
http://www.b4x.com/android/forum/threads/b4j-cctv-example.34695/

AsyncStreamsObject - Send and receive objects over the network

 

[mc73]

You can try uploading the vb6 source as well...

 

[JoanRPM]

Here is the VB6 source code.

 

[Rusty]

Did you ever find a solution? If so, what was it?
Thanks
Rusty

 

[mc73]

Ah, thanks to Rusty, I now saw that you uploaded your vb6 code. One error that I found was in your sendFile sub

 Winsock1(1).SendData (xxx)

You should instead use the index of the connected socket instead of always 1. This should err since once you open a new connection, your sub still tries to send data to a previous one. In order to do this, include in your sub's parameter's the winSocket's index and then

 winSock1(selectedSocket).sendData(xxx)

 

[JoanRPM]

Oh, thanks.
I will try.
Happy new year.

 

[JoanRPM]

No, it dosen't work.
In my example, the variable "selectedSocket" is always 1.
In my final program, I use this variable to control if there is more than one connection at the same time.
So, the problem is not solved.
Thanks again.

 

[Erel]

I recommend you to check this example: B4J CCTV example
There are two examples there. The second one supports any number of connections and properly handles disconnections.

 

[coslad]

HI JoanRPM

Have you find the problem ?

 

[JoanRPM]

No, the problem is not solved.
I let the project in stand by.

 

[coslad]

Hi ,

I found the problem , you send a not necessary byte , i attach your working source code , now works like a charm.

In the VB6 i added this

ReDim Preserve xxx(UBound(xxx) - 1) As Byte

And in B4A code i changed this:

In.InitializeFromBytesArray(aux, 0, aux.Length)

in this :

In.InitializeFromBytesArray(aux, 0, aux.Length-1)

Use like button

 

[JoanRPM]

Mmm, yes, now it works.
Thanks a lot.