Bug 355837

Summary:	Icons-only task manager: Layout broken if required space exceeds available space
Product:	[Plasma] plasmashell	Reporter:	Kai Damm <cepheus11>
Component:	Icons-only Task Manager	Assignee:	Eike Hein <hein>
Status:	RESOLVED WORKSFORME
Severity:	major	CC:	igshov, nate, plasma-bugs
Priority:	NOR
Version:	5.4.3
Target Milestone:	1.0
Platform:	Gentoo Packages
OS:	Linux
Latest Commit:		Version Fixed In:
Sentry Crash Report:
Attachments:	Snapshot 1: All is well Snapshot 2: After clicking on second icon: the two rightmost icons are gone Snapshot 3: After opening the settings window, everything is scaled way too small patch to not damage icontasks layout with a call which seems to be meant to only affect "normal" task manager test case - extract to $HOME

Description Kai Damm 2015-11-24 12:52:20 UTC

Plasma-workspace version 5.4.3.

Task buttons get hidden and unusable or are scaled unnecessarily small while plasma tries to layout the buttons in the available size of the container.

Reproducible: Always

Steps to Reproduce:
1. Create a short empty horizontal panel on the top screen edge (space for ~7 icons).
2. Add an "Icons-only task manager" as the only widget to that panel.
3. Open windows until the icons-only task manager needs to scale down the icons to fit the available space.


Actual Results:  
One of two:
1) The two rightmost icons can shortly be seen moving below to two leftmost icons, but there is no scaling or repositioning of the remaining icons. The two former rightmost icons end up out of the viewport and are inaccessible.
2) All icons are scaled so small as if there was only half the space available horizontally.

Expected Results:  
Icons get smaller and closer to each other, or a second line of icons is created (if allowed in settings)

Result of "qdbus org.kde.KWin /KWin org.kde.KWin.supportInformation":

https://bpaste.net/show/3f2a80ca7a5d

Comment 1 Kai Damm 2015-11-24 12:57:54 UTC

Created attachment 95693 [details]
Snapshot 1: All is well

Comment 2 Kai Damm 2015-11-24 12:59:10 UTC

Created attachment 95694 [details]
Snapshot 2: After clicking on second icon: the two rightmost icons are gone

Comment 3 Kai Damm 2015-11-24 13:00:12 UTC

Created attachment 95695 [details]
Snapshot 3: After opening the settings window, everything is scaled way too small

Comment 4 Kai Damm 2015-12-11 15:26:01 UTC

With plasma-5.5, icons are not rescaled at all on addition of new icons. If there is not enough width on a horinzontal panel/height on a vertical panel, new icons are not visible from the start. Rescaling only happens while the panel is resized.

Comment 5 Kai Damm 2016-04-18 06:48:49 UTC

The problem goes away with the attached patch to layout.js. The patch is based on plasma-desktop-5.5.5 (from gentoo amd64).

Comment 6 Kai Damm 2016-04-18 06:50:35 UTC

Created attachment 98440 [details]
patch to not damage icontasks layout with a call which seems to be meant to only affect "normal" task manager

Comment 7 Eike Hein 2016-04-18 21:13:16 UTC

I still can't reproduce this problem at all, and I don't want to apply patches blindly. Could you try to nail down the steps to reproduce a bit more specifically? Maybe post relevant Plasma config bits re panel size and applet config, and exact number of launchers and icons. It may well be that your patch solves it and I'll gladly take it, but I'd rather see the problem first.

Comment 8 Kai Damm 2016-04-24 12:51:50 UTC

I have prepared a ".config" with the two needed plasma config files for triggering the bug on a new user account with otherwise empty $HOME. The screen width must be 1920 pixels. There is a second control panel on the top screen edge, center aligned and very short. It contains an icons-only task manager which has five launchers. Clicking the first one makes it broader. Some other part of the layout code does not know about this and moves the fifth launcher to the left on a hypothetical second row. This animation is actually visible, but the fifth launcher is not accessible afterwards.

With no programs running, starting a program which has no launcher breaks the layout in another way: Only half of the width is used for the six icons.

Comment 9 Kai Damm 2016-04-24 12:52:26 UTC

Created attachment 98566 [details]
test case - extract to $HOME

Comment 10 Nate Graham 2017-09-05 20:10:22 UTC

*** Bug 364198 has been marked as a duplicate of this bug. ***

Comment 11 Nate Graham 2017-12-14 02:40:38 UTC

I've diligently tried to reproduce this issue in Plasma 5.11.4, following the provided Steps to Reproduce exactly (thanks for that, it's super helpful), but like Eike, I can't reproduce it. Kai, If you can reproduce in Plasma 5.11 or later, please re-open this and attach a screen recording of you reproducing the issue so we can follow along. Thanks!