Service or topic for a UI button for Ros2(noob question)

Hi everyone,
I have to program a control interface by using Ros2 humble on an embedded system.
And i don't know who is the most efficient between a service or a topic to share to other node when i am pressing a button. I don't need any answer while pressing button and the information should be spread to several nodes
However, the documentation say that the topics Should be used for continuous data streams.
I'm doubtful.