Impossible to [seriously] use 16.04 on tablets?

[hasi]

As far as I can tell, there is still no way to get a virtual keyboard running on SDDM, which is the display manager of 16.04. Same for the lockscreen. This makes Kubuntu completely unusable for anyone who wants to do serious business on a tablet. And after a lot of googling, I haven't even found any signs that this is being worked on...

That's pretty sad, given that it is 2016... People have been talking about targetting KDE for different devices ever since KDE4 (2008 or so?). We suffered through all the changes in the transition (KDE4, anyone?), and even in 2016 you still can't run it on a tablet? Seriously? So why did we move away from KDE3 again (other than I didn't find it very pretty...)?

[Feathers McGraw]

Plasma mobile is the product you should be using if you want Plasma on a tablet:

http://plasma-mobile.org/

Unfortunately it's not supported on many devices, but a virtual keyboard is obviously a core part of it.

I think the truth is that normal Plasma Desktop isn't optimised for capacitive touchscreens, and it would require a huge amount of work to make touch friendly, so the development focus has been elsewhere. If everyone used resistive touchscreens it might be different (e.g. Maemo Fremantle on N900), but that's water under the bridge now...

[oshunluvr]

I think it's presumptive to assume that all OSs should run on all devices. As the OP pointed out, some work has been done in the past to allow KDE to be used on mobile devices, the project has languished somewhat IMO. Personally, I'm not sure KDE/Plasma is suited to a small format device. I prefer an interface optimized for the uses the device is intended for. I.e. Plasma for my desktop, android for my phone. That being said, I wouldn't mind a fully open and customize-able phone OS but none of the devices on the market are usable in the US at the level I want (4G LTE GSM penta-band) so I'll stick to my Moto X for now. I was a pre-buyer of the Ubuntu phone at US $600+ but that project failed. That would have been a grand device and a worth-while experiment.

Having said all that: I am the relatively new owner of a Chinese (read "cheap" ) tablet that's dual-boot: Android and Windows 10. Maybe someday I'll dive into swapping one of the OSs for pure linux.

[hasi]

Difference capacitive vs. resistive touch screens in terms of OS?

Plasma mobile is the product you should be using if you want Plasma on a tablet. Unfortunately it's not supported on many devices, but a virtual keyboard is obviously a core part of it.

I think the truth is that normal Plasma Desktop isn't optimised for capacitive touchscreens, and it would require a huge amount of work to make touch friendly, so the development focus has been elsewhere. If everyone used resistive touchscreens it might be different (e.g. Maemo Fremantle on N900), but that's water under the bridge now...

What are the device requirements for it to be supported? If a device already supports the full version of Kubuntu/KDE, why wouldn't it run the mobile version of it?

And why is there such a big difference between capacitive vs. resistive touchscreens? As far as I am concerned to the OS the both look like some sort of a mouse, so I don't understand why the OS would look so different, depending on the kind of screen. On my particular device, (Lenovo ThinkPad Helix 1), I even have both a touch screen (to be used by fingers) and a stylus. In terms of the hardware, they are completely separate devices that can be turned on and off independently, but I both have them working very well on KDE4.

[hasi]

Personally, I'm not sure KDE/Plasma is suited to a small format device.

Touch screen doesn't necessarily mean small form factor. I have a Lenovo ThinkPad Helix 1, which is essentially a fully functional 12" laptop, where the computer is in the screen, and where the screen can be detached to work as a stand-alone tablet (both as touch screen and with stylus). In terms of form factor, everything works by far good enough for me, and on KDE4 I have everything working. However, I had to do quite a bit of hacking to make the onscreen keyboard work for both the lock screen, and the display manager (kdm). Since both the screen locker and the display manager have been redesigned from scratch, I would have to do all the hacking all over again.

I think what this really means is that KDE is not really used on anything but desktops/laptops. So all the years of talk about "convergence", the necessity to redesign all the libraries (KDE4, KDE5) etc., were not all that serious...

[oshunluvr]

Good point about the device size. I made an incorrect assumption.

Speaking of assumptions; I don't see how a situation where a free operating system desktop environment developed primarily by unpaid volunteers doesn't support a very particular piece of hardware, especially when it's a relatively young DE (speaking of plasma 5 here, but sddm is also very new) equates to debunking the seriousness of "years of talk of convergence."

I think it's more logical to assume that not enough effort has been given to the project - which is usually an indication of lack of participants for whatever reason - lack of demand comes to mind.

Additionally, if you - like Feathers and myself - would like to see the spread of linux to more devices you could voice your desires to the hardware manufacturers to support linux with drivers and the like and stop buying devices from manufacturers who don't. Also getting involved with projects like https://forums.lenovo.com/t5/Linux-D...x/td-p/1036897 might help as well. All of which leads to the point that, in a community based development structure, complaints rarely result in satisfaction but development support (like testing, trouble shooting, campaigning for linux drivers and open source) often does.

If you're smart enough to do "quite a bit of hacking" to get your touchscreen to work, you're smart enough to lend assistance to the project I suspect. However, it appears from my web searching on this issue, that you've heard this response before in the form of "where's your code?" - not something I would say to another member here. If there's any reason for lack of development in touch screen support, it's may simply be that all the developers are busy porting to QML and Wayland to have any time left for lower priority issues like yours at this time. You could always go try out Hawaii. Fiorini has QT virtual keyboard working with sddm and wayland already.

Not speaking for Feathers, but I suspect his reference to resistive vs. capacitive has to do with the enhanced sensitivity of capacitive over resistive (finer pointing abilities, etc.) but I would submit there's a very large difference between touchscreen control vs. mouse control. Mice (mouses?) are very old (trackball's invented in the 1940s were the first pointing devices) and very simple 2-D technology. Touch screens add all kinds of variations like multi-touch and pressure measurement, and add the complexities of release vs. tap vs. select, etc. I would bet there's a bit more to reprogramming the control structure. Not that it couldn't be done - it just hasn't been yet.

[Feathers McGraw]

What I meant about resistive vs capacitive screens, is that with resistive touchscreens you have pinpoint precision so you don't have to completely redesign a mouse-based UI for it to be usable. With a capacitive touchscreen, you have something more like sausage point precision, so you can't just use the old UI on a touchscreen without it being a PITA to use.

The N900 was great because it had a resistive touchscreen, which meant you could run normal linux desktop apps on it without much much modification even though the screen was much smaller than anticipated when the program was written:





I don't know what the hardware requirements are for Plasma Mobile, but it has been designed for handheld capacitive touchscreens, so they have basically adapted existing plasma widgets (like the network management widget) so that they are finger friendly (video). You can see quite a lot of progress has been made towards convergence in that video.

[LinkBot]

As far as I can tell, there is still no way to get a virtual keyboard running on SDDM,...

http://plfiorini.blogspot.fi/2016/04...on-hawaii.html

Qt Virtual Keyboard support on Hawaii

...However Qt Virtual Keyboard was a value-add component for Qt Enterprise customers, until things changed recently.

As part of the recent licensing change announcement, Qt Virtual Keyboard is now available also with GPLv3 license for Open Source users in addition to commercial Qt licensees.

This move allowed me to finally integrate Qt Virtual Keyboard with Hawaii, which soon will also be available on SDDM....