Question

我有一个列表，我也添加了玩家，玩家名称基于列表的大小。当我最初设置播放器列表时，名称是正确的，但是当我向列表中添加新播放器时，名称不正确。请帮助以下是相关代码。

将玩家添加到列表中的方法：

public static void addNewPlayers(List<Player> playerArrayList, SharedPreferences sharedPreferences,
                                 PlayerScoreCardAdapter playerScoreCardAdapter,
                                 int numberOfPlayersToAdd) {

    for (int i = 0; i < numberOfPlayersToAdd; i++) {

        // TODO: 2016-03-19 Fix player name not updating
        String name = String.format("%s%s",
                Keys.KEY_DEFAULT_PLAYER_NAME, playerArrayList.size() + 1);

        Player player = new Player(name,
                sharedPreferences.getInt(Keys.KEY_PLAYER_SCORE + String.valueOf(i + 1),
                        Keys.KEY_DEFAULT_PLAYER_SCORE));

        playerArrayList.add(i, player);
        playerScoreCardAdapter.notifyItemInserted(playerArrayList.size());
    }
}

RecylcerView.Adapter：

public class PlayerScoreCardAdapter extends RecyclerView.Adapter<PlayerScoreCardAdapter.ScoreViewHolder> {

private List<Player> mPlayerList;

public PlayerScoreCardAdapter(List<Player> playerList) {
    mPlayerList = playerList;

}

@Override
public ScoreViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {

    View view = LayoutInflater.from(parent.getContext())
            .inflate(R.layout.player_score_list_item, parent, false);

    return new ScoreViewHolder(view);
}

@Override
public void onBindViewHolder(ScoreViewHolder holder, int position) {

    holder.bindPlayers(mPlayerList.get(position));

}

@Override
public int getItemCount() {
    return mPlayerList.size();
}

public class ScoreViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener, View.OnLongClickListener {

    public TextView mPlayerName;
    public EditText mPlayerScore;
    public Button mMinusButton, mAddButton;

    public ScoreViewHolder(View itemView) {
        super(itemView);

        mPlayerName = (TextView) itemView.findViewById(R.id.textView_player_name);
        mPlayerScore = (EditText) itemView.findViewById(R.id.editText_player_score);
        mMinusButton = (Button) itemView.findViewById(R.id.button_minus);
        mAddButton = (Button) itemView.findViewById(R.id.button_add);

        mMinusButton.setOnClickListener(this);
        mAddButton.setOnClickListener(this);

        mPlayerName.setOnLongClickListener(this);


    }

    /**
     * Binds the data from the player to the appropriate views.
     *
     * @param player The player data to be bound.
     */
    public void bindPlayers(Player player) {

        mPlayerName.setText(player.getName());
        mPlayerScore.setText(String.valueOf(player.getScore()));

    }

    @Override
    public void onClick(View v) {

        int id = v.getId();
        int updatedScoreCount = mPlayerList.get(getAdapterPosition()).getScore();

        switch (id) {
            case R.id.button_minus:
                updatedScoreCount--;
                if (updatedScoreCount < 0) {
                    Toast.makeText(itemView.getContext(), R.string.toast_text_score_to_low, Toast.LENGTH_LONG).show();
                    return;
                } else {
                    updatePlayerScore(updatedScoreCount);
                    notifyItemChanged(getAdapterPosition());
                }
                break;
            case R.id.button_add:
                updatedScoreCount++;
                if (updatedScoreCount >= 9999) {
                    Toast.makeText(itemView.getContext(), R.string.toast_text_score_to_high, Toast.LENGTH_LONG).show();
                    return;
                } else {
                    updatePlayerScore(updatedScoreCount);
                    notifyItemChanged(getAdapterPosition());
                }
                break;
            default:
        }

    }

    @Override
    public boolean onLongClick(View v) {
        removePlayer(getAdapterPosition());
        return true;
    }

    public void removePlayer(int positionInArrayList) {
        mPlayerList.remove(positionInArrayList);
        notifyItemRemoved(positionInArrayList);

    }

    private void updatePlayerScore(int updatedScoreCount) {
        mPlayerList.get(getAdapterPosition()).setScore(updatedScoreCount);
    }
}

}

列表中的玩家基数从两个开始，其名称显示为玩家1和玩家2.但是当{1}传递到numberOfPlayers addNewPlayers时，玩家全部显示为玩家2。

addNewPlayer()之前和之后的列表的屏幕截图。

Answer 1

试试这个：覆盖适配器中的getItemCount以反映它正在使用的列表的大小，并调用该方法来获取列表中的项目数。

Answer 2

问题在于我将新播放器添加到列表的开头而不是列表的末尾。说实话，我确定为什么会这样，但确实如此。新代码看起来像这样。

public static void addNewPlayers(List<Player> playerArrayList, SharedPreferences sharedPreferences,
                                 PlayerScoreCardAdapter playerScoreCardAdapter,
                                 int numberOfPlayersToAdd) {

    for (int i = 0; i < numberOfPlayersToAdd; i++) {

        String name = String.format("%s%s", Keys.KEY_DEFAULT_PLAYER_NAME, playerArrayList.size() + 1);

        Player player = new Player(name, sharedPreferences.getInt(Keys.KEY_PLAYER_SCORE + String.valueOf(i + 1),
                Keys.KEY_DEFAULT_PLAYER_SCORE));

        playerArrayList.add(playerArrayList.size(), player);
        playerScoreCardAdapter.notifyItemInserted(playerArrayList.size());
    }
}

我的textView没有从list.size（）接收到正确的值，为什么不呢？

2 个答案: