### Question:
StudyActivityPresentation { public ValueModel getActivityModel() { return d_activityHolder; } StudyActivityPresentation(ObservableList<StudyActivity> activityList, SortedSetModel<Drug> drugOptions);  StudyActivityPresentation(ObservableList<StudyActivity> activityList, SortedSetModel<Drug> drugOptions, StudyActivity activity); boolean isEditing(); ValueModel getNameModel(); ObservableList<Note> getNotesModel(); ValueModel getActivityModel(); List<Activity> getActivityOptions(); TreatmentActivityPresentation getTreatmentModel(); OtherActivityPresentation getOtherActivityModel(); ValueHolder<Boolean> getValidModel(); void commit(); SortedSetModel<Drug> getDrugOptions();  }### Answer:
@Test public void testActivityModel() { StudyActivityPresentation pm1 = new StudyActivityPresentation(d_emptyList, null, d_activity); assertEquals(d_activity.getActivity(), pm1.getActivityModel().getValue()); pm1.getActivityModel().setValue(PredefinedActivity.FOLLOW_UP); assertEquals(PredefinedActivity.FOLLOW_UP, pm1.getActivityModel().getValue()); JUnitUtil.assertNotEquals(d_activity.getActivity(), pm1.getActivityModel().getValue()); }