Add missing task properties

[HerHde]

Ahoj and moin,
could you please add missing properties like categories to your implementation of tasks in ical4android?

The feature is also requested from a user of the Tasks Android app. I use the app myself and miss the categories in my other apps (Nextcloud for example). As I looked up the iCalendar specification I saw that the optional properies and those from RFC 7896 are not implemented yet, I would be very grateful if you could add (most of) them.

Thank you in advance, keep up the good work. I use some Bitfire Apps from F-Droid for years now.

Greetings
~HerHde

[ccoenen]

I, too, would greatly appreciate this!

[manuel]

This would be an awesome feature, that doesn’t seem to be hard to implement. Please consider adding support for categories!

[Bob9]

Is this being worked on? Please?

[rfc2822]

As far as I know, OpenTasks doesn’t support categories in the UI yet: https://github.com/dmfs/opentasks/issues/14

Do you know whether the backend supports categories and whether its usable or whether the UI also support categories?

[Bob9]

I’m mainly asking for the Android App “Tasks”, which uses ical4android to sync using Caldav, and already supports categories in the UI. See https://github.com/tasks/tasks/issues/635

[Bob9]

Any updates on this? Anything I can do to help?

[rfc2822]

@Bob9 It’s very complicated.

1. Not required for CATEGORIES (but for the properties of RFC 7986): These properties would ideally be implemented in ical4j, because standard properties should be in ical4j and shouldn’t require custom (extended) properties in ical4android. So, you could write a patch to get those properties into ical4j (current ical4j version: 3.x).
2. Not required for CATEGORIES (but for the properties of RFC 7986): Next problem: This would have to be backported to ical4j 2.x, because ical4j 3.x requires Java 8, which is only available at Android 7+, while DAVdroid is for Android 4.4+ and we don’t want to raise the minimum API level to Android 7 yet. So, you could make sure that those properties are available in ical4j 2.x, too. (Alternatively, you could play around to get ical4j 3.x working on Android 4.4+ with parts of the Java 8 API on older Android versions – this would be an ideal solution because ical4j 3.x is the future, but it it will be cumbersome.)
3. Then those properties would have to be implemented in the ical4android Event/Task classes. This should be quite easy.
4. To allow DAVdroid to use those properties, they should also be handled by AndroidEvent/AndroidTask, so this should be implemented too.
   • Android events don’t seem to have any category field, so we can only treat the categories as an unknown field, and for this we don’t even need to do 3) (in fact, if the Event class had a categories property, AndroidEvent would have to use and sync it to some extra field, because it wouldn’t be in the unknownProperties field anymore).
   • If OpenTasks has already categories, we can sync them there (but there is no UI yet, as far as I see).

At the moment, I don’t have time for all of this, but if you want to write patches, please don’t hesitate

[rfc2822]

Update of my previous posting: Edited 1, 2 because ical4j of course has CATEGORIES. What it doesn’t have yet are the properties of RFC 7986.

[ccoenen]

bmaehr has written some code to add categories support to ical4android, his patch is here: https://git.bmaehr.com/open-source/ical4android/commit/e36207bb64ce6f47da6d4d83b535c5ce3a85109d

Would you consider merging it, so it is in mainline ical4android?

[rfc2822]

@ccoenen AndroidEvent should be modified, too, because otherwise, DAVx⁵ would lose functionality: Now, CATEGORIES are saved in Event.unknownProperties, which are saved to the Android DB by AndroidEvent. So, DAVx⁵ saves and restores CATEGORIES at the moment as “unknown properties” without knowing anything about what CATEGORIES is and does.

As soon as Event understands CATEGORIES, they’re not being put to Event.unknownProperties anymore, so AndroidEvent doesn’t save/restore CATEGORIES anymore. The same applies to Task and AndroidTask.

So, if you could create a merge request for ical4android (soon: ical4x⁷), I’d merge it to a separate branch so that CATEGORIES can be implemented in AndroidEvent/AndroidTask, too before merging it to master.

[ccoenen]

I passed this on. Thanks for looking at this so quickly!

[ccoenen]

Another person (c64bob on GitHub) took this up again. He posted a merge request Are these two things combined what you had in mind @rfc2822 ?

[rfc2822]

@ccoenen Hello, I have merged it to https://gitlab.com/bitfireAT/ical4android/tree/support-categories. But it’s essentially the same as the first MR and only the first of the two things I have mentioned.