JScrollPane jitter during trackpad scrolling on MacOS/Aqua

[Sergey Bylokhov]

On 19/01/16 19:50, Sergey Bylokhov wrote:
> I am not sure that this is regression or a bug. In your case you scroll
> from left-down to right-up.
> But left-to-right is a scroll to up, and down-to-up is a scroll to down.
> So you scroll in both direction at the same time.

But it can be regression of JDK-8033000, I will double check.

>
> On 19/01/16 19:18, Eirik Bakke wrote:
>> Hi, macos-port-dev.
>>
>> Here's another bug report for Swing on Aqua/MacOS. In recent Java
>> versions (6-12 months, not sure), trackpad scrolling in any
>> JScrollPane has become extremely jittery, as demonstrated in the
>> following video:
>>
>> https://vimeo.com/151843642
>>
>> The source code for the example app used can be found here:
>> https://gist.github.com/eirikbakke/09a090ab8052d38c8c87
>> Note that the "implements Scrollable" business is not necessary to
>> trigger the bug, I just did it to set the getScrollableBlockIncrement
>> to something higher than 1 so that you'd see the jitter clearly on a
>> video.
>>
>> This happens in any app that uses a JScrollPane, including the
>> NetBeans IDE's code editor and other scrollable panels, as well as in
>> trivial apps like the linked example. The bug occurs consistently,
>> with or without external monitors attached, at any resolution, and
>> with or without simulated retina mode enabled. I'm on a 13-inch
>> mid-2012 MacBook Air.
>>
>> If no one knows about an existing bug report about this, I'll submit
>> it on http://bugreport.java.com<http://bugreport.java.com/> (I
>> searched bugs.openjdk.java.net ).
>>
>> -- Eirik
>>
>
>


-- 
Best regards, Sergey.