question: public void addAllUnique ( Collection < Artist > ps ) { synchronized ( mArtists ) { boolean didChange = false ; for ( Artist p : ps ) { if ( ! mArtists . contains ( p ) && p != null ) { mArtists . add ( p ) ; didChange = true ; } } if ( didChange ) { sortList ( ) ; } } }
target:  Add all the elements of the collection to the adapter if they're not already there