Re: Dynamic variables in C++ OOT for Gnu Radio 3.10

Hello Marcus,

I have made it work, by checking some of your answers before. Here are the steps, in case someone else is interested:

1. define the set_param() function in lib/myblock_imp.h file: 

     Public:

         ...

         void set_param(float param) {_param = param;}

2. Add in the lib/myblock_imp.cc file:

     _param = param;

3. In include/gnuradio/customModule/myblock.h add:

      Public:

         ...

         virtual void set_param(float param) = 0;

4. run "md5sum include/gnuradio/customModule/myblock.h" to get the tag value.

5. copy and paste the tag value in "BINDTOOL_HEADER_FILE_HASH(xxxx)" in the file python/customModule/bindings/myblock_python.cc

6. then do cmake../, make, sudo make install and sudo ldconfig. It should work now.

7. I also did "gr_modtool bind myblock", but I'm not sure if it helped or not. 

Best regards,

Wei

On Thu, 24 Apr 2025 at 11:42, Marcus Müller <mmueller@gnuradio.org> wrote:

Hi Huang Wei,

nice to have you here!

Can you show us where you use `_param` in your C++ implementation?
What you show us looks right, in general.

Best regards,
Marcus

On 4/22/25 4:56 PM, Huang Wei wrote:
> And I have added in the .yml file:
> callbacks:
> - set_param(${param})
>
> But still the value can't be changed.
>
> On Tue, 22 Apr 2025 at 15:16, Huang Wei <weizardry@gmail.com <mailto:weizardry@gmail.com>>
> wrote:
>
>     Hello everyone,
>
>     In Gnu Radio 3.10, how to set a variable in a C++ OOT block that can be adjusted
>     dynamically by a QT GUI range?
>     I did in a .h file:
>        Private:
>          float _param;
>        Public:
>          void set_param(float param) {_param = param;}
>     and in the impl.cc file:
>        _param = param;
>
>     anywhere else I need to change? I just tried before in Gnu Radio 3.7, and now I am
>     very lost with the new version.
>
>     Thank you very much.
>
>     Regards,
>     Wei
>
>