Bug 419124

Summary:	ScrollablePage freezes under certain circumstances
Product:	[Frameworks and Libraries] frameworks-kirigami	Reporter:	Jonah Brüchert <jbb>
Component:	general	Assignee:	Marco Martin <notmart>
Status:	RESOLVED FIXED
Severity:	normal
Priority:	NOR
Version First Reported In:	Master
Target Milestone:	Not decided
Platform:	Other
OS:	Linux
Latest Commit:	https://commits.kde.org/kirigami/2e9355a6e584f392d19ba870054c5fc590782921	Version Fixed/Implemented In:
Sentry Crash Report:
Attachments:	test qml file

Description Jonah Brüchert 2020-03-22 20:34:33 UTC

Created attachment 126955 [details]
test qml file

SUMMARY
If QT_QUICK_CONTROLS_MOBILE is set to true AND verticalLayoutDirection: ListView.BottomToTop is set in a ListView that is a child of a Kirigami.ScrollablePage, the ListView can then only be scrolled upwards - as soon as you try to scroll downwards (using touch gestures) the program will freeze.
Since nothing in QtQuickControls2 uses QT_QUICK_CONTROLS_MOBILE, the problem is probably in some way related to Kirigami.
See a reduced test case in the attachments.

STEPS TO REPRODUCE
1. export QT_QUICK_CONTROLS_MOBILE=true
2. qmlscene test.qml
3. scroll using touch gestures

OBSERVED RESULT
freeze

EXPECTED RESULT
scrolling in both directions works

SOFTWARE/OS VERSIONS
Operating System: Debian GNU/Linux
KDE Plasma Version: 5.18.80
KDE Frameworks Version: 5.68.0
Qt Version: 5.15.0
Kernel Version: 5.4.0-4-amd64
OS-Type: 64-bit
Processor: 4 × Intel® Core™ i5-5200U CPU @ 2.20GHz
Memory: 7,8 GiB


ADDITIONAL INFORMATION

Comment 1 Marco Martin 2020-03-25 12:34:18 UTC

Git commit 2e9355a6e584f392d19ba870054c5fc590782921 by Marco Martin.
Committed on 25/03/2020 at 12:31.
Pushed by mart into branch 'master'.

simplify header resizing

removes an undetected binding loop that may cause a freeze

M  +7    -24   src/controls/templates/AbstractApplicationHeader.qml

https://commits.kde.org/kirigami/2e9355a6e584f392d19ba870054c5fc590782921