在布局xml文件中，添加以下代码：

在activity类中添加以下代码：

public void showDatePickerDialog(View view) { DatePickerFragment fragment = new DatePickerFragment(); fragment.show(getSupportFragmentManager(), "datePicker"); }

public static class DatePickerFragment extends DialogFragment implements DatePickerDialog.OnDateSetListener {

@Override
public Dialog onCreateDialog(Bundle savedInstanceState) {
    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);
    return new DatePickerDialog(getActivity(), this, year, month, day);
}

@Override
public void onDateSet(DatePicker view, int year, int monthOfYear, int dayOfMonth) {
    String date = year + "-" + (monthOfYear + 1) + "-" + dayOfMonth;
    EditText editText_date = (EditText) getActivity().findViewById(R.id.editText_date);
    editText_date.setText(date);
}

}

然后日期选择器就能正常使用了。