@Override
    public boolean equals(Object that) {
        if ( that == null )return false;
        if ( that.getClass() != this.getClass() ) return false;
        MoveElement thatMove = (MoveElement)that;
        
        if ( thatMove.mSprites.size() != this.mSprites.size() )return false;
        for (int i = 0 ; i < mSprites.size() ; i++ )
            if (!this.mSprites.get(i).equals(thatMove.mSprites.get(i))) return false;
        
        return true;
    }