<AWT Dev> MacOS: precise scrolling is too fast

Sergey Malenkov malenkov at gmail.com
Sun Sep 25 22:38:14 UTC 2016

Hi guys,

JetBrains has some problems to continue Oracle support, and I have no
ability to submit a CR for now.  But there is a critical issue in AWT
scrolling after Sierra have been released.

I solved this issue in our custom JDK:

This fix is safe for existing third-party code, but it removes support
of precise scrolling. It is OK for now, because Swing does not support
it. I can provide another fix, but it may affect third-party
developers and requires additional changes in Swing. For example, the
following bug must be fixed in another way:
I think there are may be other issues, but I have not access to
test/closed repository to check this. Could you please move UI tests
to open-source like I did for java.beans?

I see the following steps to do:
1. fix 8166591 for comfortable scrolling in Sierra
- apply my fix (simple and almost safe) or update it
  to restore precise scrolling and fix all usages of MouseWheelEvent
2. implement new feature: Precise scrolling in Swing
- now it uses integers only
3. implement new feature: Imitate native scroll bars on Mac

I'll try to raise the issue severity as soon as we restore access to
Oracle support.

Best regards,
Sergey A. Malenkov

More information about the awt-dev mailing list