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Error in the use of SubApplication [message #1738674]

Fri, 22 July 2016 07:32

Michele Citro

Messages: 29
Registered: June 2016

Junior Member

Good morning,

I have a question for you.

When I create and use a SubApplication (example, in the creation of I/O), it can happen un error of type null pointer.

This situation causes the end of Subapplication, not more accessible.
Even if I remove the I/O of SubApplication, I don't succeed to remove it from my application.

I ask you, it is my error of "programming"?
Or, it is a problem of 4DIAC?

It seems me a loss of syncronization.
I use version 1.8M1 of 4DIAC.

I attach the result that is showed.

Best regards,
Michele Citro

Attachment: error2.png
(Size: 257.77KB, Downloaded 121 times)

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Re: Error in the use of SubApplication [message #1738677 is a reply to message #1738674]

Fri, 22 July 2016 07:51

Alois Zoitl

Messages: 1583
Registered: January 2014

Senior Member

Hi,

currently subapplications are unfortunately rather fragile. We started a major code-clean project to improve the situation. However this will not be available for the 1.8. Therefore I currently suggest to not use subapplications.

Alois

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Re: Error in the use of SubApplication [message #1738679 is a reply to message #1738677]

Fri, 22 July 2016 08:07

Michele Citro

Messages: 29
Registered: June 2016

Junior Member

Hi,

thank you for the reply.

Ok, I will do in this way. Even if, without SubApplication is more difficult write all in the "Application page".

Can I change the version of 4DIAC?
For example, at the new 1.8RC1,1.8RC2,1.8RC3.

Regards,
Michele Citro

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Re: Error in the use of SubApplication [message #1738699 is a reply to message #1738679]

Fri, 22 July 2016 12:00

Alois Zoitl

Messages: 1583
Registered: January 2014

Senior Member

Hi,

We know that subapplications are extremely important. However with the current model and code structure we where not able to fix the issues we have. Therefore better subapplication support was a key driver for us to do the major code clean-up we announced some time ago in our news. With 1.9 we expect to definitely have a more stable and better subapp support.

Yes you can alsways open your workspace /project with a newer version of 4DIAC. just download the latest 4diac and on startup select the workspace with your project. Or you can import your existing project into your workspace by selecting File->Import->Existing Project into workspace. In the wizard select your old workspace directory and then select the projects you like to import.

Furthermore you can also zip your projects and mail them arround or check them into a version control system. In 1.9 this should even get easier with less files.

Cheers,
Alois

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