App-capturing plasmoid

[Duncan]

Michael Mol posted on Tue, 17 Jan 2017 10:35:31 -0500 as excerpted:

> Eons ago, there was a dockapp for WindowMaker that could capture an X11
> application and contain its window within the dockapp tile.
> 
> The equivalent for KDE Plasma would be a plasmoid which would wrap an
> application.
> 
> Is there such a thing? It'd be insanely useful; I'd love to be able to
> capture a Chrome window as a widget on the desktop, for example; I'd be
> able to stick my ticket tracker view in a widget, open a ticket in a new
> tab, drag that tab out into a separate window. I could also embed
> virt-manager. But, really, Chrome would be my biggest use case; having
> that shared cookie and sync state would be helpful; the lack of it is a
> big part of why I stopped using the web widget.

The closest thing I'm aware of is the now legacy and phasing out support 
for iconizing an app to the systray.  That _used_ to be an option in the 
menu editor (I _believe_ that's where I used to see it), but I'm 
following plasma git and the plasma devel list, and a recent commit 
removed the functionality, as long discouraged and after the commit, with 
no GUI (tho I didn't read close enough to see if it removed the 
functionality if the appropriate lines were manually added to the 
*.desktop file).  I _think_ that was around in the kde3 era, and it was 
certainly an option in kde4, but while the option stuck around into 
plasma5, I'm not sure how well it worked.

Talking about which... to my knowledge, it never _did_ work really 
_well_, at least not for non-kde/non-qt apps.  I tried it years ago for 
pan (a gtk2 or 3 based nntp client that worked better for binaries back 
when I chose it than knode), which I have configured to start with kde/
plasma, but decided it didn't work well enough to be worth the trouble.  
IIRC it sort of worked, but you still had to be careful to minimize the 
window instead of closing it, as closing it would actually quit the app 
instead of just closing the window and leaving it running in the systray, 
as expected.  So I continued using the minimize, and when pan eventually 
got systray functionality of its own, I used that (despite it still not 
working _quite_ right, it closes to the tray when the window close icon 
is clicked, and clicking the tray icon brings it back to view, but 
clicking the tray icon with it open doesn't do much of anything, gotta 
close it via the titlebar, which I'd possibly otherwise hide, as I do for 
both my claws-mail mail and feeds instances).  After finding it didn't 
work well for that because hitting the titlebar close icon still 
terminated the app instead of simply closing the window to the tray, I 
didn't try it on anything else.

So it wasn't really practical for me, and I imagine the same behavior 
made it less than practical for most users, unless it was fixed at some 
point and I just never knew it as I didn't try it again.  That being the 
case, I imagine the functionality won't be much missed.

But even were it working, it doesn't sound like that's quite what you're 
looking for anyway, thus the "closest" wording in my initial sentence.  
I'm not aware of anything that would actually wrap an app and put it on 
the desktop or in some other container (panel, etc) as a plasmoid 
widget.  I agree, it'd be nice and potentially quite useful, however, to 
have such a thing.

Back in the kde4 era there was a potentially huge problem with it -- 
plasma was single-threaded and any misbehaving plasmoid could freeze the 
entire desktop, panels and all, one of my biggest complaints about kde4 
era plasma, as it was an absolutely _horrible_ idea to make an 
environment that encouraged all sorts of third party plugins, as plasma 
did with its plasmoids, single-threaded-blockable by just one of them 
misbehaving in some way.  I had one system-monitor style plasmoid I ran 
that did just that a few times when the output from a tracked sensor 
wasn't available (until the author realized the problem and made the 
monitor simply continue with a blank readout in that case, but that 
shouldn't have been necessary as the hosting environment should have been 
robust enough to disallow that in the first place).

But I'm not sure plasmashell 5 is subject to the same limitations.  I do 
see multiple threads for it in htop, tho only a couple in addition to the 
main thread, and I've not seen the same problems with it, but that could 
just as easily be due to the more limited set of third party plasmoids 
I've seen for it, at least on kdelook, and the fact that qt-quick 
scripted plasmoids are strongly encouraged now, with actual binary 
plasmoids close to non-existent, if they're supported at all (I don't 
actually think they are, in 5, possibly /because/ of the problems with 
what the binary-based plasmoids could and did do in 4).

-- 
Duncan - List replies preferred.   No HTML msgs.
"Every nonfree program has a lord, a master --
and if you use the program, he is your master."  Richard Stallman