proper handling of custom date range selections - fixes #611 (#639)

app/src/main/java/org/gnucash/android/ui/util/dialog/DateRangePickerDialogFragment.java

@@ -52,6 +52,7 @@ public class DateRangePickerDialogFragment extends DialogFragment{
     private Date mStartRange = LocalDate.now().minusMonths(1).toDate();
     private Date mEndRange = LocalDate.now().toDate();
     private OnDateRangeSetListener mDateRangeSetListener;
+    private static final long ONE_DAY_IN_MILLIS = 24 * 60 * 60 * 1000;
 
     public static DateRangePickerDialogFragment newInstance(OnDateRangeSetListener dateRangeSetListener){
         DateRangePickerDialogFragment fragment = new DateRangePickerDialogFragment();
@@ -89,7 +90,11 @@ public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle sa
             public void onClick(View v) {
                 List<Date> selectedDates = mCalendarPickerView.getSelectedDates();
                 Date startDate = selectedDates.get(0);
-                Date endDate = selectedDates.size() == 2 ? selectedDates.get(1) : new Date();
+                // If only one day is selected (no interval) start and end should be the same (the selected one)
+                Date endDate = selectedDates.size() > 1 ? selectedDates.get(selectedDates.size() - 1) : new Date(startDate.getTime());
+                // CaledarPicker returns the start of the selected day but we want all transactions of that day to be included.
+                // Therefore we have to add 24 hours to the endDate.
+                endDate.setTime(endDate.getTime() + ONE_DAY_IN_MILLIS);
                 mDateRangeSetListener.onDateRangeSet(startDate, endDate);
                 dismiss();
             }