Freezes in uitk

[Michael Zanetti]

Ever since moving to uitk 1.3, I see occational freezes, mostly related to page push/pop operations. This happens very randomly but causes the app to freeze and requires a restart.

I've triggered such freezes in many situations in all sorts of different apps but never could really reproduce it. There is definitely a race condition involved. Such freezes seem to happen most likely directly after app startup when pressing a button in the toolbar while stuff is still loading, but not only. I've also seen it happening in the middle of using an app.

Now a friend of mine wrote an app and managed to get into a situation where it reliably triggers a freeze. I am not sure if this is the same as I'm observing or if its a different one. However, it is a freeze and might lead us to the real reason. Attached you'll find an archive that allows reproducing at least that one variant of the freeze.

[Tim Peeters (tpeeters)]

Confirmed by running 'qmlscene Main.qml' in the attached archive, then clicking 'Continue' and then 'Kill' button. The result is that the UI is not responsive, I cannot click the 'Continue' button any more.

[Tim Peeters (tpeeters)]

The dialog is created with the context of the Page. When closing the dialog, it starts to fade out, and then the page is popped (and destroyed) before the dialog fade-out is finished. This makes the context of the dialog invalid, and the ScriptAction that makes the dialog invisible (and destroys it) is not executed. Because of this, the dialog stays active (but with opacity 0) and blocks events from getting to the active page.

[Łukasz Zemczak (sil2100)]

This bug was fixed in the package ubuntu-ui-toolkit 1.3.1949+15.04.20160421 in https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/stable-phone-overlay

---------------

ubuntu-ui-toolkit (1.3.1949+15.04.20160421) vivid; urgency=medium

  [ Zoltan Balogh ]
  * Make pep8 happy with all the python scripts of the UITK project.
    Fixes LP: #1454322, LP: #1572981

  [ Tim Peeters ]
  * Update Header.flickable docs. Fixes LP: #1572525
  * Fix app freeze after closing Dialog/Popover. Fixes LP: #1568016.
  * Fix the tests for focus restoration in tst_focus.qml. Fixes LP: #1572983
  * Update PageStack unit tests to use PageHeader. Fixes LP: #1572988

  [ Pierre Bertet ]
  * Minor optimization on the palette values declaration.

  [ Christian Dywan ]
  * Allow SEGFAULTing tests to be flagged as exceptions. Fixes LP: #1572990

  [ CI Train Bot ]
  * No-change rebuild.

 -- Zoltan Balogh <email address hidden> Thu, 21 Apr 2016 12:06:31 +0000

[Launchpad Janitor (janitor)]

This bug was fixed in the package ubuntu-ui-toolkit - 1.3.1984+16.10.20160527.2

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ubuntu-ui-toolkit (1.3.1984+16.10.20160527.2) yakkety; urgency=medium

  [ Christian Dywan ]
  * Slimmer frame for TextFields: 0.5dp. Fixes LP: #1578190.

  [ Albert Astals Cid ]
  * Add override
    The override specifier (since C++11) specifies that a virtual function
    overrides another virtual function. In a member function declaration or
    definition, override ensures that the function is virtual and is overriding
    a virtual function from the base class.

  [ Tim Peeters ]
  * Fix reference error in PullToRefreshStyle. Fixes LP: #1582843
  * Mark Tab, Tabs, TabBar, PageHeadConfiguration, PageHeadSections,
    PageHeadState, ToolbarButton, ToolbarItems as deprecated in the
    documentation. Fixes LP: #1566735, LP: #1566741.

  [ CI Train Bot ]
  * Resync trunk.

 -- Zoltan Balogh <email address hidden> Fri, 27 May 2016 07:08:44 +0000