How to create a Google/Safari extension with ability to override audio playing in a tab?

Question

I am trying my hand at developing my own Safari extensions that could perform basic Pandora commands from the an extension menu (with an open tab streaming from the Pandora site). I'm just wondering if there is a way I can programmatically mute my Pandora music if I were to play a YouTube video from another tab? I've seen it done on a Google Chrome extension called "SoundControl" but have no idea whether it is at all possible to implement on Safari. Any suggestions or reference to the safari manual would be appreciated. Thanks!

Answer 1

Add an event listener to your code like this:

safari.application.addEventListener("activate", activateHandler, true);

    function activateHandler(event) {
        if(event.target.activeTab.url.indexOf("youtube") != -1)
         {
            //Pause your player in here
         }  
    }

Look at music player tutorial in here

Window or tab activated event tutorial is in here