RB.ShellPlayer::playing-changed

def callback(shell_player, playing, user_param1, ...)

Emitted when playback either stops or starts.

shell_player :

instance of RB.ShellPlayer that is emitting the signal

playing :

flag indicating playback state

user_param1 :

first user parameter (if any) specified with the connect() method

... :

additional user parameters (if any)