有没有办法用Robolectric测试采摘器？

Question

我正在关注Android开发人员的教程。 现在我的班级看起来像这样：

public class DatePickerFragment extends DialogFragment implements
        DatePickerDialog.OnDateSetListener {

    final Calendar calendar = Calendar.getInstance();

    @Override
    public Dialog onCreateDialog(Bundle savedInstanceState) {
        return new DatePickerDialog(getActivity(), this,
                calendar.get(Calendar.YEAR), calendar.get(Calendar.MONTH),
                calendar.get(Calendar.DAY_OF_MONTH));
    }

    @Override
    public void onDateSet(DatePicker view, int year, int month, int day) {
        calendar.set(year, month, day);
        Datable datable = (Datable) view.getContext();
        datable.setDate(calendar.getTime());
    }

}

如果我尝试运行如下所示的测试，我在第一个getDataPicker()上得到一个NullPointerException。 我想检查默认日期是否为今天。

@Test
public void testDatePickerFragment() {
    final Calendar calendar = Calendar.getInstance();
    int expectedYear = calendar.get(Calendar.YEAR);
    int expectedMonth = calendar.get(Calendar.MONTH);
    int expectedDay = calendar.get(Calendar.DAY_OF_MONTH);

    DatePickerFragment fragment = new DatePickerFragment();

    FragmentActivity activity = Robolectric
            .buildActivity(FragmentActivity.class).create().start()
            .resume().get();

    FragmentManager fragmentManager = activity.getSupportFragmentManager();
    FragmentTransaction fragmentTransaction = fragmentManager
            .beginTransaction();
    fragment.show(fragmentManager, "datePicker");
    fragmentTransaction.commit();

    DatePickerDialog dialog = (DatePickerDialog) ShadowDatePickerDialog
            .getLatestDialog();

    assertThat(dialog, is(not(nullValue())));

    assertThat(dialog.getDatePicker().getDayOfMonth(), is(expectedDay));
    assertThat(dialog.getDatePicker().getMonth(), is(expectedMonth));
    assertThat(dialog.getDatePicker().getYear(), is(expectedYear));
}

我希望能够在不在活动中使用它来测试这个类（在这种情况下，我相信我可以使用buildActivity方法，然后使用ShadowDatePickerDialog但这是下一步）。

那么，是否可以测试datePicker？ 我正在使用robolectric 2.2

Answer 1

它适用于新版Robolectric 3.X. 你可以尝试这样的事情：

    startDate.performClick();
    DatePickerDialog dialog = (DatePickerDialog) ShadowDatePickerDialog.getLatestDialog();
    dialog.updateDate(2013, 10, 23);
    dialog.getButton(DatePickerDialog.BUTTON_POSITIVE).performClick();
    assertEquals("2013-11-23", startDate.getText().toString());