How to store a unique ID in a GDataEntryCalendarEvent object

[unforgiven]

The problem I am facing is how to store in a GDataEntryCalendarEvent
object a unique ID that will not change even if the event is modified
or deleted. I tried using the GDataEntryBase setIdentifier: method
without succeeding: the identifier is always modified server side. So,
I am wondering how to accomplish this. Is one of the following
GDataEntryBase options viable?

1) setETag:

2) setResourceID:

Or GDataEntryCalendarEvent setICalUID: ?

If not, how to do this? Is there any available snippet of source code
showing how to do this?
Thank you in advance.

[unforgiven]

Ok, it seems that using an extended property may work.
Is there any problem using this approach? Can the server modify
arbitrarily the contents of extended properties or are these safe to
use for my purpose?

[Greg Robbins]

An entry's identifier is permanent, but it is set by the API server, not by the client app.

Extended properties are the only arbitrary data that the server will retain for the developer.

Specific rules about preservation of that data are up to the specific API.

Calendar's extendedProperty docs are at

http://code.google.com/apis/calendar/data/2.0/developers_guide_protocol.html#ExtendedProps

For additional questions about its support for extended properties, try the Calendar API forum,

http://code.google.com/apis/calendar/community/forum.html

[unforgiven]

Thank you very much.
With kind regards,

Massimo

On Oct 25, 5:41 pm, Greg Robbins <grobb...@google.com> wrote:
> An entry's identifier is permanent, but it is set by the API server, not by
> the client app.
>
> Extended properties are the only arbitrary data that the server will retain
> for the developer.
>
> Specific rules about preservation of that data are up to the specific API.
>
> Calendar's extendedProperty docs are at
>

> http://code.google.com/apis/calendar/data/2.0/developers_guide_protoc...