How to create custom plugin based on another custom plugin?

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Not sure if this question makes sense and sorry for that as I am new.

I have a protocol sent over UDP and successfully made a plugin to parse the header information based on"UDP.port". I followed the guide here: https://www.wireshark.org/docs/wsdg_h... to create the header plugin and my parser is very similar. Each packet in my protocol contains different parameters based on what is read in the header. Now I want to further dissect the data with one of many custom plugins based on the first 4 bytes of the header, this would be based on "CUSTOM.id" similar to the header being based on UDP.

How can I create a second plugin to decode the rest of the data depending on what is read in the header? I am putting my plugins here: plugins/epan/.