android - 将数据从 DialogFragment 发送到 Fragment

Question

我有一个包含 EditText 的 fragment ，当我单击该 EditText 时，会出现一个 DatePicker 对话框来选择日期。
fragment 文件

public class FirstFragment extends Fragment {
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_first, container, false);
        EditText editText = (EditText) view.findViewById(R.id.visitDateFiled);

        editText.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment picker = new DatePickerFragment();
                picker.show(getFragmentManager(), "Date Picker");
            }
        });
        return view;
    }

对话框 fragment

public class DatePickerFragment extends DialogFragment
        implements DatePickerDialog.OnDateSetListener {

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the current date as the default date in the picker
        final Calendar c = Calendar.getInstance();
        int year = c.get(Calendar.YEAR);
        int month = c.get(Calendar.MONTH);
        int day = c.get(Calendar.DAY_OF_MONTH);
        // Create a new instance of DatePickerDialog and return it
        return new DatePickerDialog(getActivity(), this, year, month, day);
    }

    @Override
    public void onDateSet(DatePicker view, int year, int month, int day) {
        Calendar c = Calendar.getInstance();
        c.set(year, month, day);

        SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
        String formattedDate = sdf.format(c.getTime());

    }
}

问题我不知道如何将数据(选定的日期)从DialogFragment传递到Fragment？
我读了一些主题，但这对我感到困惑没有帮助(抱歉再次问这个问题)。

Topic 1 Topic 2

Answer 1

更新了代码

fragment 文件

public class FirstFragment extends Fragment implements DatePickerDialogFragmentEvents{
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_first, container, false);
        EditText editText = (EditText) view.findViewById(R.id.visitDateFiled);

        editText.setOnClickListener(new View.OnClickListener() {
            @Override
            public void onClick(View view) {
                DialogFragment picker = new DatePickerFragment();
                picker.setDatePickerDialogFragmentEvents(FirstFragment.this); //Changed
                picker.show(getFragmentManager(), "Date Picker");
            }
        });
        return view;
    }

    //This is where you will get selected date value
    @Override
    public void onDateSelected(String date) {
        String selectedDate = date;
    } 
 }

对话框 fragment

public class DatePickerFragment extends DialogFragment
        implements DatePickerDialog.OnDateSetListener {

    //Interface created for communicating this dialog fragment events to called fragment
    public interface DatePickerDialogFragmentEvents{
       void onDateSelected(String date);
    }

    DatePickerDialogFragmentEvents dpdfe

    public void setDatePickerDialogFragmentEvents(DatePickerDialogFragmentEvents dpdfe){
         this.dpdfe = dpdfe;
    }

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        // Use the current date as the default date in the picker
        final Calendar c = Calendar.getInstance();
        int year = c.get(Calendar.YEAR);
        int month = c.get(Calendar.MONTH);
        int day = c.get(Calendar.DAY_OF_MONTH);
        // Create a new instance of DatePickerDialog and return it
        return new DatePickerDialog(getActivity(), this, year, month, day);
    }

    @Override
    public void onDateSet(DatePicker view, int year, int month, int day) {
        Calendar c = Calendar.getInstance();
        c.set(year, month, day);

        SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
        String formattedDate = sdf.format(c.getTime());
        dpdfe.onDateSelected(formattedDate); //Changed
    }
}

所以我在dialogfragment类中创建了一个名为DatePickerDialogFragmentEvents的接口(interface)，并在调用者 fragment 中实现了它。当您创建dialogfragment实例时，从调用者 fragment 中，使用对话框 fragment 类的setDatePickerDialogFragmentEvents方法设置 fragment 的DatePickerDialogFragmentEvents实例。