QML Flickables scrolling with mouse wheel insanely fast

this happens also for real scroll wheels

It appears that the internal USC default for scroll speed is 1.0 (on a scale of 0.0 to 1.0). But the default that unity8 will start using once [1] lands is 0.5. So I *think* this will be solved by that (already approved) branch. But unfortunately, it's a little hard to test that right this second, because it has a complicated dependency chain. But once I do, I will mark this bug accordingly.

[1] https://code.launchpad.net/~mterry/unity8/new-input-proxies/+merge/285364

Yup, after testing silo 64, this seems to be fixed.

I've tested the silo with the updated system settings and the scrolling speed in particular does not seem to be working well.

The setting seems to be applied, in a way, since if you go low enough it stops scrolling altogether.

As far as I can tell by testing and inspecting code, the value (MouseScrollSpeed) is getting correctly set by System Settings. Which is getting proxied to USC. Which is getting applied by Mir.

In Mir, the value (0.0 to 1.0) is used as a multiplier against how far to scroll. The Mir default used to be 1.0. With silo 64, it's now 0.5.

When I wrote comment #3, I remember feeling a distinct difference between 1.0 and 0.5 (the new default). I'm having a hard time feeling that difference today.

But I'm guessing whatever issues we have with silo 64 are probably at the Mir level(?). I *think* the value is traveling down to Mir intact.

If we want to land silo 64 before we figure out why this setting doesn't feel right, we could hide the setting in the meantime...

Ah! I do see a difference between 1.0 and 0.5. In comment #3, I was testing on slashdot.org in the browser. When I wrote comment #5, I was testing the dash. The browser still works fine. For some reason, scrolling in the dash is a different kind of scrolling... I think the branches are fine today, we just need to investigate dash scrolling.

W dniu 11.03.2016 o 15:02, Michael Terry pisze:
> Ah! I do see a difference between 1.0 and 0.5. In comment #3, I was
> testing on slashdot.org in the browser. When I wrote comment #5, I was
> testing the dash. The browser still works fine. For some reason,
> scrolling in the dash is a different kind of scrolling... I think the
> branches are fine today, we just need to investigate dash scrolling.

Ah indeed, that's what I was testing, too.

TBH we know that QML's scrolling in Flickables is broken, so that would
be it.

This bug was fixed in the package unity8 - 8.11+16.04.20160310.4-0ubuntu1

---------------
unity8 (8.11+16.04.20160310.4-0ubuntu1) xenial; urgency=medium

  [ Albert Astals Cid ]
  * Add context for Re-dock as asked by translators (LP: #1534608)
  * Add emblem to the preview header widget (LP: #1424720)
  * Add haptics to ScopesListCategoryItem buttons
  * Audio Cards: Make some of the image loading async (LP: #1533432)
  * Do not create fallback code for the card tool fake card (LP:
    #1545865)
  * Fix resizing the dash bringing temp scopes size out of sync (LP:
    #1543130)
  * Minor fixes for unity-scope-tool
  * Resolve title alignment on card creator time instead of on runtime
  * Use fixedHeaderHeight only in the non cardtool cards
  * Use the new undeprecated connectivityqt::Connectivity
  * asynchronous is only false on the fake card in cardtool
  * clazy fixes

  [ Albert Astals Cid, CI Train Bot ]
  * click scope: Add the else branch so we reset the card size in all
    situations

  [ Andrea Cimitan ]
  * PreviewSharing widget now accepts both string and array of
    widgetData["share-data"]["uri"] (LP: #1549056)
  * Update AP tests for new single preview
  * Use Text.Wrap for body notification text (LP: #1544909)

  [ Andrea Cimitan, Lukáš Tinkl, Michael Zanetti, Nick Dedekind ]
  * some fixes for the new palette (LP: #1554616)

  [ CI Train Bot ]
  * Resync trunk.
  * Update translation template

  [ CI Train Bot, Daniel d'Andrada ]
  * Ensure the QML engine doesn't delete our mock MirSurfaces on its
    own.

  [ Daniel d'Andrada ]
  * tst_Shell: Remove unused qml items

  [ Josh Arenson ]
  * Allow the shell to blacklist input devices and force the OSK shown.
    (LP: #1542224)

  [ Lukáš Tinkl ]
  * Disallow resizing windows up, past the Panel (LP: #1544766)
  * Elide the window title not to let it overflow into the indicators
    area (LP: #1535767)
  * Enable the PIN lockscreen to be used with a HW keyboard (LP:
    #1550359)
  * Fix tiny windows when switching stages
  * Provide a range of ports to QML JS Debugger
  * Watch for launcher item icon changes (LP: #1543290)

  [ Michael Terry ]
  * Proxy more mouse and touchpad properties to USC (LP: #1540398) (LP:
    #1543344, #1540398)
  * Refactor the AccountsService plugin and make it slightly faster.
  * To let the user log in if a mouse is connected, hide the greeter
    cover page on a mouse click (but NOT a touch click). (LP: #1540497)
  * Watch AccountsService for changes to the user's real name. This was
    preventing us from noticing when the user set their name in the
    welcome wizard.

  [ Michael Zanetti ]
  * Allow alt+tabbing in staged mode too (LP: #1540502)
  * Allow invoking the staged mode spreads by mouse right edge pushes
    too (LP: #1540392)
  * Allow loading the device configuration from an external file
  * Implement Launcher's keyboard navigation and updated pip design
  * Make launcher scalable, allow it locking (LP: #1511015)
  * Properly parent launcher items in all cases (LP: #1495732)
  * Read inputMethod surface from the new property int QtMir (LP:
    #1545286)
  * Some visual updates and rotation lock for the virtual touchpad (LP:
    ...

Status changed to 'Confirmed' because the bug affects multiple users.

Re-opening since QML is still busted

With the attached simplified test case I can't see difference between Qt 5.4 and 5.6, and scrolling seems normal on both. I'm using mako attached to monitor and I tried to scroll both with the "touchpad" and a Bluetooth mouse attached.

I'd like to have a test case with just QtQuick 2.0 import so that there would be something to submit a bug report to upstream with, in case the problem persists with Qt 5.6.

I think this bug can now be marked as duplicate of the better described bug #1607240 which also has a ubuntu-system-settings sub-task.

I'm not completely sure this is a duplicate of bug 1607240 because that one technically never existed in a form that users of non-X11 apps would notice. Because Unity8 was also defaulting to slowing down scrolling by a similar amount, which was a guestimate hack that kept most apps scrolling at the right speed.

We only had to fix the whole stack (bug 1607240) in order to get high precision touchpad scrolling implemented recently.

Maybe bug 1556795 is a better description?

I'm going to say duplicate of bug 1556795. But please also see bug 1605513.