NVDA_17.3: NVDAObjects. Potential unimplemented child class in Windows7

[surfer0627]

Steps to reproduce:

1. Press win+m to minimize all windows.
2. Press downArrow several times.

Expected behavior:

NVDA moves smoothly.

Actual behavior:

NVDA reports list items a little bit lag

System configuration:

NVDA version: 2017.3 Installed
Windows version: windows7 64bit (6.1.7601 service pack 1)

Other questions:

In the same case, NVDA 17.3 portable will crash while pressing Win+m to minimize all windows.
The issue does not occur in NVDA2017.2.

LOG Message:

Input: kb(desktop):downArrow
DEBUG - NVDAObjects.NVDAObject._get_placeholder (09:58:09.059):
Potential unimplemented child class: <NVDAObjects.IAccessible.sysListView32.ListItem object at 0x0646A6D0>
IO - braille.BrailleBuffer.update (09:58:09.170):
Braille regions text: [u'c\u96fb\u8166 32 of 32']
IO - braille.BrailleHandler.update (09:58:09.170):
Braille window dots: 14 145 2345 5 1345 146 4 - 25 23 - 135 124 - 25 23

[josephsl]

Hi, uh oh, @feerrenrut, any ideas, or is this even serious enough? Re #7004 Edit: Removed quoted email.

[LeonarddeR]

@surfer0627: Can you reproduce this issue with braille disabled?

[surfer0627]

When braille disabled, NVDA still reports list items a little bit lag. The difference is that log message "Potential unimplemented child class" is disappeared.

@LeonarddeR

[ruifontes]

Hi! It only happens with a Braille display in use... Rui

…

-----Mensagem Original----- De: Leonard de Ruijter Data: 28 de agosto de 2017 05:08 Para: nvaccess/nvda Cc: Subscribed Assunto: Re: [nvaccess/nvda] NVDA_17.3: NVDAObjects. Potential unimplemented child class in Windows7 (#7532) @surfer0627: Can you reproduce this issue with braille disabled? — You are receiving this because you are subscribed to this thread. Reply to this email directly, view it on GitHub, or mute the thread.

[LeonarddeR]

@ruifontes commented on 28 aug. 2017 12:30 CEST:

It only happens with a Braille display in use...

Could you elaborate?

[ruifontes]

Hi! If you are using a Braille display, in my case a Handytech BB20 or a Orbit Reader 20, the error occurs. If you choose "No display", the error does not occurs.

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-----Mensagem Original----- De: Leonard de Ruijter Data: 28 de agosto de 2017 11:35 Para: nvaccess/nvda Cc: ruifontes ; Comment Assunto: Re: [nvaccess/nvda] NVDA_17.3: NVDAObjects. Potential unimplemented child class in Windows7 (#7532) @ruifontes commented on 28 aug. 2017 12:30 CEST: It only happens with a Braille display in use... Could you elaborate? — You are receiving this because you commented. Reply to this email directly, view it on GitHub, or mute the thread.

[feerrenrut]

The "Potential unimplemented child class" message can safely be ignored. In terms of the lag, @surfer0627 could you please attach the full log. I would like to compare the timestamps on the log messages to try to understand what user action triggers it.

[surfer0627]

@feerrenrut: Please check the attached log file. Thanks.

nvda_17.3_installed.log.txt

[feerrenrut]

According to the log, it seems like there is a delay of around 400ms. I don't seem to be able to reproduce this myself using he brailleViewer driver on Windows 10 and NVDA master-14328,c6379eb3. @surfer0627 Could you attach a log file after doing the same thing, with braille disabled?

[surfer0627]

@feerrenrut:

I don't know why? but, the truth is that I could not reproduce this case in braille display enabled / disabled.

[feerrenrut]

@surfer0627 Are you able to reproduce the issue? If not I will close it.