Small Update:
Release 2.5.1 is out now, fixing that issue:
I can confirm your results from step 1 to step 5.
This is indeed a bug that needs fixing; I have added it as
http://jira.xwiki.org/browse/MOCCACAL-91
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>
> 1. Created new XWiki 7.4 instance - distribution wizard doesn't start for
> some reason so I installed the default pages using
> xwiki-enterprise-ui-mainwiki-all-7.4.xar.
> 2. Installed MoccaCalendar extension and verified that version is 2.5 (full
> calendar macro is version 2.0.2)
> 3. Logged in as Admin and created a new calendar (first to verify behaviour
> without your suggested mods to JSON Service).
> 4. In the new calendar created an event - event is displayed as expected.
> 5. In the new calendar, tried to create another event with the same title -
> event form displays 'An event with this name already exists.' under the
> title field.
> 6. In the new calendar, tried to create another event with no title - event
> form displays 'Title field is required'.
> 7. Deleted event created in step 4.
> 8. In class editor MoccaCalendarEvent class added new field 'Test' of type
> String.
> 9. Navigated to /xwiki/bin/view/MoccaCalendar/JSONService -> Edit -> Source
> and replaced $itemdoc.getPlainTitle() with $itemdoc.getValue('Test') in two
> places as you suggested.
> 10. Returned to new calendar created in Step 3.
> 11. Invoked form to create an event - event form is displayed with new Test
> field (blank). But the Title field is populated with a random string and the
> Calendar drop down field where you can select which calendar the event
> belongs to is missing from the form.
> 12. Entered a value in the Test field and saved the event - the form
> disappears but the event is not displayed on the new calendar.
> 13. Navigated to Calendar Overview and observed that new event is displayed
> there with the content of the Test field instead of the Title. Here the
> event is displayed on the Month view the way I want it.
>
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