gnome-panel cannot show newly installed software icons

[Wei Tsui]

1) First => sudo apt-get install gnome-session-flashback

2) Then => re-login user with "Gnome Flashback (Metacity)" session

3) Next => install a software that does not exist in gnome-panel menu list previously, such as "sudo apt-get install mousepad"

However, after installion of mousepad, its icons doesn't show in gnome-panel menu list. I have to:

4) killall gnome-panel

5) gnome-panel &

Then, the mousepad icon can be shown in gnome-panel menu list.

This might be caused by forgetting to update icon menu list from gnome-panel

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: gnome-panel 1:3.18.1-1ubuntu3
ProcVersionSignature: Ubuntu 4.2.0-19.23-generic 4.2.6
Uname: Linux 4.2.0-19-generic x86_64
ApportVersion: 2.19.2-0ubuntu6
Architecture: amd64
CurrentDesktop: GNOME-Flashback:Unity
Date: Mon Nov 23 06:13:43 2015
GsettingsChanges:

JournalErrors:
 Error: command ['journalctl', '-b', '--priority', 'warning'] failed with exit code 1: Hint: You are currently not seeing messages from other users and the system.
       Users in the 'systemd-journal' group can see all messages. Pass -q to
       turn off this notice.
 No journal files were opened due to insufficient permissions.
SourcePackage: gnome-panel
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[Alberts Muktupāvels (muktupavels)]

Is that on clean install?

[Wei Tsui (ghostplant)]

Yes, clean install for part of softwares will cause this bug.

See Also, https://bugs.launchpad.net/ubuntu/+source/gnome-panel/+bug/1530555

And the reason is simple, the menu from gnome-panel will display a new item if a new "desktop" file is created in /usr/share/application/ folder, but the menu will check whether "TryExec=" points to a non-exist file or an invalid link, if so, the menu still hide this item even after the target that "TryExec=" points to become valid.

One of the following solutions can fix this bug,

1. force dpkg to postpone installing "[DEB]/usr/share/applications/*" files in the deb package, in order to make the file that "TryExec=" points to become valid first.

2. add a trigger after every dpkg installation finish to force updating the whole menus.

3. force gnome-panel to ignore "TryExec=" field to let menu item always show.

[Dmitry Shachnev (mitya57)]

This looks like an issue in upstream gnome-menus (i.e. it occurs in Unity too), so I have filed a bug upstream. Unfortunately, it looks like gnome-menus is no longer developed upstream, so the chances to get it fixed are not that high…

[Dmitry Shachnev (mitya57)]

For Unity a workaround has been proposed in lp:~azzar1/libunity/fix-1506744 (details are in bug 1506744). Maybe it's possible to do something similar in gnome-flashback?

[Alberts Muktupāvels (muktupavels)]

We could use timeout before re-loading menu in gnome-panel, but how big timeout we should use?

[Dmitry Shachnev (mitya57)]

I think any timeout should work. How about 20 seconds?

[Alberts Muktupāvels (muktupavels)]

Patch for testing.

[Ubuntu Foundations Team Bug Bot (crichton)]

The attachment "menu: reload application menu after 10 second delay" seems to be a patch. If it isn't, please remove the "patch" flag from the attachment, remove the "patch" tag, and if you are a member of the ~ubuntu-reviewers, unsubscribe the team.

[This is an automated message performed by a Launchpad user owned by ~brian-murray, for any issues please contact him.]

[Dmitry Shachnev (mitya57)]

Andrea has uploaded a different patch for gnome-menus which adds a two seconds timeout (in gnome-menus 3.13.3-6ubuntu4).