Can reproduce on Neon 5.13.

Can confirm on Arch which uses the latest plasma 5.13. Just started happening after the upgrade from 5.12. Does not happen on Kubuntu 18.04 running plasma 5.12. Folder view widget only displays one folder at a time when it is in the panel. Found nothing of consequence when looking at the plasma-org.kde.plasma.desktop-appletsrc file. Tried removing and reinserting with no joy. Same thing happened on my backup Arch system which I don't use but keep updated. The act of updating alone broke it.

*** This bug has been marked as a duplicate of bug 394420 ***

This bug is not the same as bug #394420. Bug #394420 deals with the folder view appearing on the panel with too much space. Later in the comments, somebody wrote about the too-small-popup, but that should have been filed as a separate bug, as it is here. Reopening.

Created attachment 113487 [details]
What it should look like [Kubuntu 18.04]

This is what it used to look like, until Plasma 5.13

Created attachment 113488 [details]
What it looks like on Arch [same exact folder structure]

After updating Arch to Plasma 5.13, this is what happened. I can't even use my mouse scroll wheel to select what I want which makes it useless now.

Confirmed on Neon packages and with Kubuntu testing builds

I wasn't able to reproduce this so far.

If I manually revert the changes from:

https://cgit.kde.org/plasma-desktop.git/commit/?h=Plasma/5.13&id=2683d4c6e60a9b8cca32f9b342d9010f4cc46086

I seem to get a functional panel folderview again

This issue is totally related to folderview changing from CompactRepresentation to FullRepresentation and vice versa...

As mentioned also at https://bugs.kde.org/show_bug.cgi?id=394420 if the user sets a very high panel icon size e.g. 256px it should be solved...

Can confirm on 5.13.1 on Debian.

Created attachment 113715 [details]
Set from detail mode to icon mode. Icon size largest

Took the folder view shown in my previous screenshots and set the mode to icon with the largest possible icon size which I believe is 256px. Immediate expansion on the panel.

(In reply to Jeff Smith from comment #12)
> Created attachment 113715 [details]
> Set from detail mode to icon mode. Icon size largest
> 
> Took the folder view shown in my previous screenshots and set the mode to
> icon with the largest possible icon size which I believe is 256px. Immediate
> expansion on the panel.


1. did you use 256px for the panel icon size from the plasma systemsettings?
2. did you try a relogin afterwards?

Created attachment 113716 [details]
Still in icon mode. Set to smallest icon.

To further prove OUR point, set the icon to minimum while still in icon mode. Sorta kinda usable but the panel still has all that empty space. I don't know about you but I need all the panel space I can get.

Created attachment 113717 [details]
Set from icon mode back to list mode. Icon size still set to smallest.

Even better, but still not right and the extra panel space is still being used. The only way to correct that extra panel space from the bug https://bugs.kde.org/show_bug.cgi?id=394420 is to delete the folder view and start over which of course takes US back to the reason for this bug report. I will of course not use it this way because I need my panel space. Please fix.

Michail Vourlakos asked,

1. did you use 256px for the panel icon size from the plasma systemsettings? NO
2. did you try a relogin afterwards? NO

I set the icon size to the largest in system settings and logged out and back in. The folder view widget (and I mean both of them in the panel including the one that I did not modify) are back to normal. This seems to be a good workaround and I seriously hope it does get fixed properly. So please lets keep this bug report open until it does.

(In reply to Jeff Smith from comment #16)
> Michail Vourlakos asked,
> 
> 1. did you use 256px for the panel icon size from the plasma systemsettings?
> NO
> 2. did you try a relogin afterwards? NO
> 
> I set the icon size to the largest in system settings and logged out and
> back in. The folder view widget (and I mean both of them in the panel
> including the one that I did not modify) are back to normal. This seems to
> be a good workaround and I seriously hope it does get fixed properly. So
> please lets keep this bug report open until it does.

What do you consider a proper fix?
According to plasma devs the proper fix is to set the panel icon size correctly.
All this has been discussed at: 

https://bugs.kde.org/show_bug.cgi?id=394420
https://phabricator.kde.org/D11220
https://phabricator.kde.org/D11651

If the plasma team decides for a better solution, I can implement it.

Why can't this be fixed to work like it did before, where it was actually useful without taking up a crazy amount of horizontal space in the panel?

In the past, I've used a folder view icon on the panel to bring up a quick access list of frequently used files. In Plasma 5.13, the files list window is too small to be of any use, and if I make the icon space super-wide, then I'm losing a ton of space on an already cramped panel. A feature that was once a major part of my workflow has now become unusable :(

There's likely going to be changes to it. There's two problems currently:

a) I can't reproduce it on my system at all. I need to set up something where I can reproduce it first.

b) I am currently very busy and in the middle of travel preparations, so I haven't had time for it.

I may or may not find some time this week. In the meantime any other dev is very welcome to look into it to.

Michail, note the problem people are having here isn't the applet expanding on the panel, it's the popup being very tiny.

(In reply to Eike Hein from comment #20)
> Michail, note the problem people are having here isn't the applet expanding
> on the panel, it's the popup being very tiny.

they are relevant because it happens when the folderview is switching from single icon in the panel to FullRepresentation and vice versa. You can use Latte in order to reproduce.

Way to reproduce:
1. Revert my commit (https://phabricator.kde.org/D11651) for panel icon in order for FolderView to execute always the code:

    Plasmoid.switchWidth: preferredWidth(true)
    Plasmoid.switchHeight: preferredHeight(true)

2. Open Latte and disable the parabolic effect
3. Add a folderview in Latte
4. Close Latte and re-open it.
5. Click the FolderView in Latte it should work ok
6. Enable the parabolic effect in Latte and hover the folderview in order to change to FullRepresentation
7. disable the parabolic effect again in Latte in order for FolderView in Latte to stick in icon
8. Click the folderview and you will see the problem, whatever you change afterwards in folderview settings the popup will be always very small


* 1) If you dont revert my commit then the problematic code cant be accessed except if your panel has bigger thickness than the panel icon size (this is why the proposal to set panel icon size to 256px. fixes the issue after relogin)
* 2) the code that breaks is from preferredWidth(true)/preferredHeigth(true) and  it needs also the plasmoid to change in the panel from CompactRepresentation to FullRepresentation and vice versa

I found a way to reproduce easier with plasma panel:

1. Add a folderview in a plasma panel
2. Click the folderview and the popup should look just fine
3. Increase the panel thickness until the folderview shows as FullRepresentation
4. Restore the panel thickness in order for the folderview to look as icon
5. Click the folderview and you will notice the problem. Whatever you do afterwards the popup should always look very small

Thanks, that helps a lot. I think this is fixable; I'll look into it soon.

I can confirm I can reproduce this behavior on
KDE Plasma Version 5.13.2 (openSUSE-Leap) and 5.13.1 (openSUSE Tumbleweed).
(KDE Framework Version 5.47.0)
Logging out of the session and logging in again restores a useful preview (popup) size again.

This patch should solve all the issues as well as make FV behave better on panels in general: https://phabricator.kde.org/D13870

FYI: The initial patch upload was missing some stuff, it's been updated now.

Thank you Eike. Really appreciate the quick fix.

Not allowing full view on a horizontal panel is a top notch fix. Thanks Eike.

Git commit 4ad27c62b5e71dcf143c5e5a96d9127de38c7d2d by Eike Hein.
Committed on 04/07/2018 at 19:41.
Pushed by hein into branch 'Plasma/5.13'.

Correct Folder View sizing and representation switch behavior

Summary:
* Resolve inherent layout hint conflicts between full and compact
  representations by setting them seperately.
  This fixes a recent regression causing tiny popups.
* Correctly respect the panel icon size hint when scaling the
  compact representation, with the code and behavior now matching
  the Icon applet.
* Only expand into the full representation in place on vertical
  panels. This is not a bugfix, and optional. But I think the
  expansion is useless on horizontal panels, and this means fewer
  users have to care about changing the panel icon size hint if
  they're using a really tall horizontal panel or Latte with
  parabolic zooming.

Reviewers: mart, broulik, mvourlakos

Subscribers: plasma-devel

Tags: #plasma

Differential Revision: https://phabricator.kde.org/D13870

M  +11   -0    containments/desktop/package/contents/ui/CompactRepresentation.qml
M  +29   -9    containments/desktop/package/contents/ui/main.qml

https://commits.kde.org/plasma-desktop/4ad27c62b5e71dcf143c5e5a96d9127de38c7d2d

*** Bug 396304 has been marked as a duplicate of this bug. ***