Hi David,
Making the parameter vary at runtime is simple and just needs some extra XML
and python code. The parameter should be an argument to the __init__ method
(constructor) of your block and should have a "" declaration in the matching
XML file. Let's say the parameter name is "variable_param" with a declaration
like:
Variable parameter
variable_param
42
int
Then you need to add the following in the XML file:
set_variable_param($variable_param)
And you need to implement the "set_variable_param" method in your python class
to take whatever action is needed when the parameter value changes. This method
will be called every time the value of the expression in the underlined
"Variable parameter" box in the GUI changes. The method will look like:
def set_variable_param(self, new_value):
whatever code
This should make GRC underline the variable_param in the GUI and it will be
variable at runtime.
Thanks,
--Patrick
________________________________
> From: mcqui...@sfu.ca
> Date: Thu, 24 Sep 2015 10:35:34 -0700
> To: david.ha...@toshiba-trel.com
> CC: discuss-gnuradio@gnu.org
> Subject: Re: [Discuss-gnuradio] Function Probe and OOT Blocks
>
> Hi David:
>
> I'm a relative newbie myself, but I can say that I had this same issue.
> I had a block with a static parameter that I wanted to be able to
> change dynamically at runtime.
>
> I looked at the block's source code, and also at a block that had a
> dynamically adjustable parameter.
>
> Basically, and with a little help from the list (Marcus Muller in
> particular) as I had to learn c++, I was able to use the code from the
> dynamic block as an example, and modify the static block to change the
> parameter to be dynamically changeable. It all came down to at most a
> couple dozen lines of code. The bigger challenge was learning about
> Gnuradio's architecture, to know what to do.
>
> I would suggest a similar approach. You will find the list members
> very helpful. I'd also look at the guided tutorials, there are good
> examples there under "how to write a c++ block".
>
> I will help if I can but alas, I am still quite a newbie, so others
> will be able to help much more efficiently!
>
> Kevin
>
> Sent from my iPad
>
> On Sep 23, 2015, at 4:12 AM, David Halls
> <david.ha...@toshiba-trel.com>
> wrote:
>
>
> Hi guys,
>
>
> I am familiar with using function probes to update values to blocks.
> This is straightforward with built in blocks like Multiply Const, where
> the input is underline in the GRC dialogue box.
>
>
> How do I create a block, specifically a Python block, that allows me to
> update parameters in this fashion so that they are not fixed at
> runtime?
>
>
> Regards,
>
>
> David
>
> ________________________________
>
> NOTE: The information in this email and any attachments may be
> confidential and/or legally privileged. This message may be read,
> copied and used only by the intended recipient. If you are not the
> intended recipient, please destroy this message, delete any copies held
> on your system and notify the sender immediately.
>
> Toshiba Research Europe Limited, registered in England and Wales
> (2519556). Registered Office 208 Cambridge Science Park, Milton Road,
> Cambridge CB4 0GZ, England. Web:
> www.toshiba.eu/research/trl
>
>
>
> ________________________________
> This email has been scanned for email related threats and delivered
> safely by Mimecast.
> For more information please visit http://www.mimecast.com
> ________________________________
> _______________________________________________
> Discuss-gnuradio mailing list
> Discuss-gnuradio@gnu.org
> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
>
> _______________________________________________ Discuss-gnuradio
> mailing list Discuss-gnuradio@gnu.org
> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
> _______________________________________________
Discuss-gnuradio mailing list
Discuss-gnuradio@gnu.org
https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
