Ui_media play/pause video option with ui_button

Hello. I'm new in programming, and I'm having some problems using the ui_media node using external buttons to play/pause the video in the dashboard. It only works when I use the "show controls" option in the node, but I want to activate the video using ui_button node. I tried sending a bool true and false msg to the media node, but doesn't work for me. Anyone can help me please? Thanks