gistfile1.rb

class MyApplication < NSApplication
    def sendEvent(event) 
        if event.type == NSSystemDefined && event.subtype == 8 #determine if one of the media keys was pressed
            keyCode = (event.data1 & 0xFFFF0000) >> 16
            keyFlags = event.data1 & 0x0000FFFF
            keyState = (keyFlags & 0xFF00) >> 8 == 0xA
            mediaKeyPressed(keyCode) if keyState
            super(nil) #don't passing anything on to super
        else
            super(event) #not what we were looking for, pass the event on to super.
        end
    end
    
    def mediaKeyPressed(keyCode) 
        if keyCode == 20 #previous track key was pressed
            NSNotificationCenter.defaultCenter.postNotificationName('MyApplicationPreviousTrack', object:nil)
        elsif keyCode == 19 #next track key was pressed
            NSNotificationCenter.defaultCenter.postNotificationName('MyApplicationNextTrack', object:nil)
        elsif keyCode == 16 #play/pause key was pressed
            NSNotificationCenter.defaultCenter.postNotificationName('MyApplicationPlayToggle', object:nil)
        end
    end
    
end