question: public boolean showCard ( String tag , boolean dismissible ) { final Card card = mHiddenCards . get ( tag ) ; if ( card != null && ! mVisibleCards . containsValue ( tag ) ) { mHiddenCards . remove ( tag ) ; mVisibleCards . put ( tag , card ) ; mLayout . addCard ( card . getView ( ) , dismissible ) ; if ( dismissible ) { mDismissibleCards . add ( tag ) ; } return true ; } return false ; }
target:  Show a card, returns false if the card could not be shown.