微调器 setOnItemSelectedListener 的问题

Question

当我的片段在 onCreateView 微调器 OnItemSelectedListener 中时 运行！但是选择了 none 个选项 片段：

public class AppDataUsageFragment extends Fragment{
    Spinner spinner;
    String[] date_array = new String[]{"Day","Week","Month","Year","Custom"};
    public AppDataUsageFragment() {
        // Required empty public constructor
    }
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.app_data_usage_fragment, container, false);

        spinner = view.findViewById(R.id.spinner);
        spinner.setAdapter(new ArrayAdapter<String>(context,android.R.layout.simple_dropdown_item_1line,date_array));

        date_sp.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
                @Override
                public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
                    GetData(); // ********* THIS RUN WHEN NOTHING SELECT BY USER ***********
                }

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

                }
            });

        return view;
    }

Answer 1

避免在初始化期间调用spinner.setOnItemSelectedListener()

spinner.setSelection(Adapter.NO_SELECTION, true); //Add this line before setting listener
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
    @Override
    public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {

    }

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

    }
});