Extend python document observer capabilities

[ickby]

Hello,

for a small python project of mine I need some comprehensive document observation capabilities. This is done via document observers, however, some key things are not yet observable. Hence I implemented some additions to the current capabilities:

- Finished recompute for objects and the whole document
- Transactions: open, commit and abort
- onBeforeChange for notifications of properties that are about to be changed
- document property changes
- Add/Remove dynamic properties to objects
- New Gui document observer, for added viewproviders and changes to viewprovider properties
- Start/Finish edit mode of viewproviders

Furthermore I added testcases for all the python document observer capabilities.

Pull request:
https://github.com/FreeCAD/FreeCAD/pull/1707

Regards,
Stefan

[microelly2]

Thank you for sharing this, I see nice new possibilities.

[damian]

Thank you

+1

[DeepSOIC]

Nice!
Also wanted:
* aboutToSaveDocument (for save, save-as, save a copy, save on exit, but not for auto backups)
* onDocumentSaved

[ickby]

Werner merged and also considered DeepSOICs whiches. Thanks!

[wmayer]

There two further slots: slotStartSaveDocument and slotFinishSaveDocument.
In case you have to distinguish between the three save methods then:
* for saveAs you have to use slotBeforeChangeDocument or slotChangedDocument because it notifies you when the FileName property changes
* for saveCopy you can compare the passed file name with FileName. If they are different then saveCopy is invoked

[yorik]

This document observer is becoming a pretty powerful thing... Thanks folks!

[Kunda1]

Can someone with technical understanding volunteer to document this ?

[Kunda1]

Can someone with technical understanding volunteer to document this ?

Opened a request on the FC Dev Blog, anyone interested in contributing ?
https://github.com/FreeCAD/FreeCAD-blog/issues/6

[DeepSOIC]

There two further slots: slotStartSaveDocument and slotFinishSaveDocument.
In case you have to distinguish between the three save methods then:
* for saveAs you have to use slotBeforeChangeDocument or slotChangedDocument because it notifies you when the FileName property changes
* for saveCopy you can compare the passed file name with FileName. If they are different then saveCopy is invoked

Thanks!