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@David, Niklas

If while working in an open document you loose your place, believe you can
always use the <F6> key to safely cycle back through the main menus to your
location in the open document--NVDA will announce "Document View Document
editable".  And you should be located back at the last cursor position with
a refreshed  frame buffer of accessible objects showing on the page.
These two URLs give mostly correct and complete Shortcuts (a.k.a.
Accelerators) for use in LibreOffice (or Apache OpenOffice).

I've checked current LibreOffice and LODev 4.2.0 builds, as well as
Apache OpenOffice 4.0.1 release with NVDA 2013.2 and Java JRE 1.7u40 on
Windows 7.  Following changes that Mic and Jamie have made to NVDA at 2013.2
( ) NVDA has been very stable
with paging events while parsing Java Accessibility Bridge delivered

I'm comfortable saying that LibreOffice releases (and Apache OpenOffice
4.0.1) are correctly functioning.   If you beleive we've got a bug
issue--we'll need to pin down a specific test case to be able to reproduce.

I also tested with the current r1527279 build of the AOO IA2 branch.  Very
good fidelity and response to page movements there as to be expected with
this native Windows accessibility bridge consumed by NVDA.

So several things are in play here.  First a little structural history:  due
to the the way the Java Access Bridge structures its view of accessible
objects in a given frame the UNO Accessibility API has been limited and does
not fully expose complete document structure to Assistive Technology.

The "native" OS X and Linux bridges are not greatly affected when document
paging occurs as they operate directly to map the native UNO Accessibility
API roles and functions for their own API needs.  In a sense they can keep
up with scrolling and paging actions.

That is not true for the Java Access Bridge link to the JRE Accessibility
framework  which can have considerable latency and overhead with each page
action that moves the portion of the document that is in frame beyond what
is held in buffer.   In short, the Java Framework of accessible objects for
the page buffer must be rebuilt in response to actions passed with the JAB.

Over on the Apache OpenOffice project side, the main trunk of the Apache
OpenOffice, including this weeks release of AOO 4.0.1,  continues to use the
Java Access Bridge to connect UNO Accessibility API events to the Java
Accessibility Framework. 

However, work is ongoing on the ia2 branch.  That effort (undertaken by IBM
Beijing and building on code contributed from the Lotus Symphony suite)  is
implementing the IAccessible2 based  API that will provide a native bridge
of UNO Accessibility API for Windows platforms.   This is an alternative to
Microsoft's User Interface Automation and because IAccessible2 IDF is
maintained by the Linux Foundation's Open Accessibility  (A11y)
workgroup--it has many of the same functional design goals as the Linux
(A11y) ATK and AT-SPI projects.    An OpenSource project it is more
appropriate for Apache and TDF to be the basis for the "native" Wndows --
UNO Accessibility API bridge.

The ia2 branch r1527279 build was just rebased onto the current AOO 4.0.1
trunk.  Because it is not dependent on Java Access Bridge, the Java Runtime
Environment does not even have to be activated for use from Tools -> Java,
and the JRE does not have to have Java Access Bridge enabled.  The
IAccessible2 roles and functions passed to Windows and consumed by NVDA for
this "native" bridge are not sensitive to paging movements as is the
JRE/JAB.  Also, more roles and functions have been defined--so the ia2 build
is more completely rendering the GUI.

Unfortunately, merging of IAccessible2 bridge as a Windows OS native
Accessibility Bridge will potentially impact the other native "bridges" and
will require refactoring and design of the UNO Accessibility API for both
projects.   My understanding is that the IA2 branch will be merged for
release as AOO 4.1.0.  And that thus far no development effort to use the
now fully ALv2 code has been started by the LibreOffice Engineering Steering
Committee--I'd expect that to start at some point.

In the interim, we have to continue to test AT support using JRE/JAB (or
being developed using IAccessible2) and keep on guard for regressions
introduced with changes to UAA and the bridges.


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