如何从DatePickerFragment调用视图

Question

W/RepoOperation﹕ Persisted write at /30987733 failed: FirebaseError: Invalid token in path

logcat的：

package org.jaberrio.personai2;

import android.app.DatePickerDialog;
import android.app.Dialog;
import android.app.DialogFragment;
import android.content.Context;
import android.os.Bundle;
import android.widget.DatePicker;
import android.widget.TextView;

import java.util.Calendar;

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);
}

public void onDateSet(DatePicker view, int year, int month, int day) {


    DataBaseManager dataBaseManager = new DataBaseManager();
    String date = String.valueOf(month) + "/" + String.valueOf(day) + "/" + String.valueOf(year);
    dataBaseManager.tempSaveCurrentEvent(DataBaseManager.FieldTypes.DUE_DATE,date, getActivity().getApplicationContext());

    TextView dueDate = (TextView)view.getRootView().findViewById(R.id.dueDate);
    dueDate.setText(dataBaseManager.tempGetCurrentEvent(DataBaseManager.FieldTypes.DUE_DATE,getActivity().getApplicationContext()));
}
}

我正在调用dueDate.setText（）但是它返回null。我调用了view.getRootView（），因为我在DatePicker的视图中，因此它应该返回包含我的dueDate TextView的视图。我也可以从调用DatePickerFragment的方法传递View，但我不知道如何。我猜测调用getRootView（）时DatePicker视图不会返回包含R.id.dueDate的视图。提前谢谢。