question: public void addAction ( Action act ) { if ( act . entry != null && act . entry != this ) { Log . e ( TAG , "addAction failed. Already applied to another notification - " + act . entry . ID + ". Current notification is " + ID ) ; return ; } if ( mActions == null ) { mActions = new ArrayList < Action > ( ) ; } if ( mActions . size ( ) == 3 ) { Log . w ( TAG , "only suppport up to 3 actions." ) ; return ; } act . entry = this ; mActions . add ( act ) ; }
target:  Add a action to this notification. Actions are typically displayed as a button adjacent to the notification content.