Android访问按钮的父视图

Question

我有一个充气行列表，其中包含两个TextView和两个按钮。按钮应增加/减少其中一个textViews。但是，当我尝试实现它时，我无法从onclickListener中获取正确的标记。它给出了一个空指针异常。我有一个holder和convertview实现，Holder确实为convertview设置了标签。更具体地说，我需要能够获取convertview的标记以更改行的值。

我把星星放在我认为重要的部分旁边。

这是适配器代码

class PlayerAdapter extends ArrayAdapter<Player> {

    private ArrayList<Player> players;
    private Context cont;
    private Player temp;



    public Player getTemp() {
        return temp;
    }

    public void setTemp(Player temp) {
        this.temp = temp;
    }

    public Player getItem(int index){
        return players.get(index);
    }

    public PlayerAdapter(Context context, int layoutId, int textViewResourceId, ArrayList<Player> items) {
            super(context,layoutId, textViewResourceId, items);
            players = items;
            cont = context;

    }

    @Override
    public View getView(int position, View convertView, ViewGroup parent) {


        ViewHolder holder;


        if(convertView == null){
            LayoutInflater inflater =getLayoutInflater();
            convertView = inflater.inflate(R.layout.player_slot,null);

             holder = new ViewHolder(convertView, position);
             holder.player_name = (TextView) convertView.findViewById(R.id.name);
             holder.player_score = (TextView) convertView.findViewById(R.id.score);
             holder.dec_score = (Button) convertView.findViewById(R.id.decrement);
             holder.inc_score = (Button) convertView.findViewById(R.id.increment);
             convertView.setTag(holder);


        }
        else holder = (ViewHolder) convertView.getTag();



        Button dec = (Button)convertView.findViewById(R.id.decrement);
        Button inc =(Button)convertView.findViewById(R.id.increment);
        TextView name = (TextView)convertView.findViewById(R.id.name);
        TextView score = (TextView)convertView.findViewById(R.id.score);

        System.out.println("tag = " +dec.getTag());

        Player temp = getPlayer(position);
        System.out.println(temp.getPlayer_name() + temp.getPlayer_score());
        if(temp != null){
            //holder.player_name.setText(temp.getPlayer_name());
            //holder.player_score.setText(""+temp.getPlayer_score());
            name.setText(temp.getPlayer_name());
            score.setText(""+temp.getPlayer_score());
        }

        dec.setOnClickListener(new OnClickListener(){
                private Button dec;

            @Override
            public void onClick(View v) {
                // TODO Auto-generated method stub

            int position =  (Integer) ((View)v.getParent()).getTag();//***
            Player temp = getPlayer(position);
            System.out.println("Player "+ temp.getPlayer_name() + "'s score changed");
            temp.setPlayer_score(temp.getPlayer_score()-1);//**
            PlayerAdapter.this.notifyDataSetChanged();
            }

        });


        return convertView;
    }

}