我正在创建一个 SportsApp，在我的 NFL 页面中，用户可以在其中选择他们想要查看的周，它不会显示用户选择的周，但会显示正确的数据。微调器显示默认的第 1 周文本，但加载所选周的正确值。

 public class NFLWeekSpinner extends Fragment {

    Spinner NFLspinner;
    ArrayAdapter<CharSequence> spinnerAdapter;
    String inputWeekFormatted;

    @Nullable
    @Override
    public View onCreateView(LayoutInflater inflater, @Nullable ViewGroup container, Bundle savedInstanceState) {

        View view = inflater.inflate(R.layout.nfl_spinner_frag,container,false);
        NFLspinner = view.findViewById(R.id.NFLSpinner);

        spinnerAdapter = ArrayAdapter.createFromResource(this.getActivity(),R.array.weekNum,
                android.R.layout.simple_spinner_item);
        //spinnerAdapter.setDropDownViewResource(android.R.layout.simple_dropdown_item_1line);
        NFLspinner.setAdapter(spinnerAdapter);

        NFLspinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {

            boolean user = false;

            @Override
            public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

                if(user) {
                    String selectedWeek = (String) parent.getItemAtPosition(position);
                    if (selectedWeek.length() > 6) {
                        inputWeekFormatted = selectedWeek.substring(5, 7);
                    } else {
                        inputWeekFormatted = selectedWeek.substring(5, 6);

                    }
                    ((MainActivity) getActivity()).loadNFLscoreboard(inputWeekFormatted);
                }
                user = true;

                // count++;
            }

            @Override
            public void onNothingSelected(AdapterView<?> parent) {

            }

        });



        return view;

    }
 @Override
    public void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);

    }

}

MainActivity.java

public class MainActivity extends AppCompatActivity {

    private static final String BACK_ROOT_STACK = "root_fragment";
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        DateFormat sdf = new SimpleDateFormat("yyyyMMdd");

        //loadMLBScoreboard(defaultDate);
        loadNavBar();
    }
    public void loadNavBar() {

        final BottomNavigationView mBottomNav = findViewById(R.id.bottom_navigation);
        final String defaultDate = "20180915";
        mBottomNav.setItemIconTintList(null);
        mBottomNav.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                mBottomNav.setItemIconTintList(null);

                switch (item.getItemId()) {
                    case R.id.menu_nfl:
                        loadNFLscoreboard("1");
                        break;
                    case R.id.menu_baseball:
                        DateFormat sdf = new SimpleDateFormat("yyyyMMdd");


                        String today = sdf.format(Calendar.getInstance().getTime());
                        loadMLBScoreboard(defaultDate);
                        break;

                        default:

                            loadMLBScoreboard(defaultDate);
                }
                return true;
            }
        });
    }

    public void loadMLBScoreboard(String inputDate) {

        LoadScoreboardFragment loadScoreboardFragment = new LoadScoreboardFragment();

        loadMLBFragment(inputDate, loadScoreboardFragment);
    }

    private void loadMLBFragment(String inputDate, LoadScoreboardFragment loadScoreboardFragment) {
        Bundle bundle = new Bundle();

        //Load date Fragment
        DateFragment dateFragment = new DateFragment();

        bundle.putString("inputDateKey", inputDate);
        loadScoreboardFragment.setArguments(bundle);

        FragmentManager fragmentManager = getFragmentManager();
        FragmentTransaction newFT = fragmentManager.beginTransaction();
        newFT.add(loadScoreboardFragment, "Loading");
        newFT.replace(R.id.holderFragment, dateFragment)
                .addToBackStack(BACK_ROOT_STACK)
                .commit();
    }
    public void loadNFLscoreboard(String nflWeek) {
        LoadNFLscoreboardFragment loadNFLscoreboardFragment = new LoadNFLscoreboardFragment();
        NFLWeekSpinner weekSpinner = new NFLWeekSpinner();

        Bundle bundle = new Bundle();

        bundle.putString("inputWeekKey",nflWeek);
        loadNFLscoreboardFragment.setArguments(bundle);

        FragmentManager fragmentManager = getFragmentManager();
        fragmentManager.beginTransaction()
                .replace(R.id.main_recycle, loadNFLscoreboardFragment)
                .commit();

            fragmentManager.beginTransaction()
                    .replace(R.id.holderFragment,weekSpinner)
                    .addToBackStack(BACK_ROOT_STACK)
                    .commit();
      }
    }

R.array.WeekNum

 <string-array name="weekNum">
    <item>Week 1</item>
    <item>Week 2</item>
    <item>Week 3</item>
    <item>Week 4</item>
    <item>Week 5</item>
    <item>Week 6</item>
    <item>Week 7</item>
    <item>Week 8</item>
    <item>Week 9</item>
    <item>Week 10</item>
    <item>Week 11</item>
    <item>Week 12</item>
    <item>Week 13</item>
    <item>Week 14</item>
    <item>Week 15</item>
    <item>Week 16</item>
    <item>Week 17</item>
</string-array>

最佳答案

我终于明白了!!!在 NFLSpinner.OnItemSelected 调用中，一旦用户选择了新的一周，我就会调用 MainActivity loadNFLScoreboard 方法，该方法会在每个周上创建 Spinner 的新实例称呼。我将 NFLWeekSpinner 声明移到了 loadNFLScoreboad 方法之外，因为每次调用都没有创建新的微调器，所以所选的星期会正确显示。

感谢您的帮助@lionscribe

关于android - 如何修复 Spinner 在 fragment 中调用 OnItemSelected 后未正确显示所选项目？，我们在Stack Overflow上找到一个类似的问题： https://stackoverflow.com/questions/54337359/