getArguments().getInt() 从“1”开始返回，而不是“0”

Question

请帮我解决一下？

我有一个带有 ViewPager 和 5 个 RecyclerViewFragment 的 Activity，每个 RecyclerFragment 都包含动态 CardView。

ViewPager 适配器的代码：

public class CustomFragmentPagerAdapter extends FragmentStatePagerAdapter {

    private Board board;
    private long boardID;

    public CustomFragmentPagerAdapter(FragmentManager fm, Board board, long id) {
        super(fm);
        this.board = board;
        this.boardID = id;
    }

    @Override
    public int getCount() {
        return 5;
    }

    @Override
    public CharSequence getPageTitle(int position) {
        return board.getMyLists().get(position).getName();
    }

    //Here I define fragment, int position - is a position of Fragment in ViewPager
    @Override
    public Fragment getFragment( int position) {
        **return RecyclerViewFragment.newInstance(boardID, position);**
    }
}

接下来是 Fragment 的新实例：

public static RecyclerViewFragment newInstance(long id, int listPosition){
    Bundle args = new Bundle();
    args.putLong(BUNDLE_ID, id);
    args.putInt(BUNDLE_LIST_POSITION, listPosition);
    RecyclerViewFragment fragment = new RecyclerViewFragment();
    fragment.setArguments(args);
    return fragment;
}

我通过 Bundle 存储 片段的位置 - listPosition

然后我通过getArguments()

在OnCreateView中得到那个位置

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    boardID = this.getArguments().getLong(BUNDLE_ID);
    listPosition = this.getArguments().getInt(BUNDLE_LIST_POSITION, 0);
    return inflater.inflate(R.layout.fragment_recyclerview, container, false);
}

所以问题是，当我从 getArguments() 获得 int-Position 时，它有下一个序列 - 1,2,3,4,0。但是它按这个顺序写 - 0,1,2,3,4

可能你认为这无关紧要，但 Realm ORM 确实是相反的。当我从数据库中获取有关动态 CardView 的信息时，Realm 从第 0 个片段开始，而 getArguments() 从 1 开始。那东西抛出

ArrayIndexOutOfBoundsException

[更新] 我添加了 Log.d 到 newInstance 和 OnCreateView

public static RecyclerViewFragment newInstance(long id, int listPosition){
    Bundle args = new Bundle();
    args.putLong(BUNDLE_ID, id);
    Log.d(TAG, listPosition + " Before put");
    args.putInt(BUNDLE_LIST_POSITION, listPosition);
    Log.d(TAG, listPosition + " After put");
    RecyclerViewFragment fragment = new RecyclerViewFragment();
    fragment.setArguments(args);
    return fragment;
}

@Nullable
@Override
public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
    tinyDB = new TinyDB(getContext());
    boardPosition = tinyDB.getInt("boardPosition");
    boardID = this.getArguments().getLong(BUNDLE_ID);
    listPosition = this.getArguments().getInt(BUNDLE_LIST_POSITION, 0);
    Log.d(TAG, listPosition + " Get ");
    return inflater.inflate(R.layout.fragment_recyclerview, container, false);
}

然后在 LogCat 我得到下一个：

06-12 00:37:46.188 25265-25265/com.treggo.flexible D/mLogs: 0 Before put
06-12 00:37:46.188 25265-25265/com.treggo.flexible D/mLogs: 0 After put
06-12 00:37:46.188 25265-25265/com.treggo.flexible D/mLogs: 1 Before put
06-12 00:37:46.188 25265-25265/com.treggo.flexible D/mLogs: 1 After put
06-12 00:37:46.188 25265-25265/com.treggo.flexible D/mLogs: 2 Before put
06-12 00:37:46.188 25265-25265/com.treggo.flexible D/mLogs: 2 After put
06-12 00:37:46.189 25265-25265/com.treggo.flexible D/mLogs: 3 Before put
06-12 00:37:46.189 25265-25265/com.treggo.flexible D/mLogs: 3 After put
06-12 00:37:46.189 25265-25265/com.treggo.flexible D/mLogs: 4 Before put
06-12 00:37:46.189 25265-25265/com.treggo.flexible D/mLogs: 4 After put
06-12 00:37:46.190 25265-25265/com.treggo.flexible D/mLogs: 1 Get 
06-12 00:37:46.266 25265-25265/com.treggo.flexible D/mLogs: 2 Get 
06-12 00:37:46.322 25265-25265/com.treggo.flexible D/mLogs: 3 Get 
06-12 00:37:46.397 25265-25265/com.treggo.flexible D/mLogs: 4 Get 
06-12 00:37:46.452 25265-25265/com.treggo.flexible D/mLogs: 0 Get

P.S。为了绕过异常，我设置了 9 个 CardView，而不是从 Realm

读取它

Answer 1

虽然我不知道你是如何实现列表位置的索引的，但从这个问题来看，我假设它是从 1 开始的，而不是 0。

如果是这种情况，请在您的 newInstance() 方法中替换以下行：

args.putInt(BUNDLE_LIST_POSITION, listPosition);

有了这个：

args.putInt(BUNDLE_LIST_POSITION, listPosition - 1);

getArguments().getInt() 从“1”开始返回，而不是“0”

getArguments().getInt() starts returning from "1", instead "0"

android

bundle

realm

android-fragments

android-recyclerview