Tk on raspberry pi

Donald Arseneau

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Mar 10, 2018, 10:42:31 PM3/10/18

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I'm wondering if anyone has experience with Tk on a raspberry pi with
its "Touch Display". Does it work without a lot of fuss? I won't have
stringent demands, just button presses and dragging sliders, not multi-
touch (but I would like touch-and-drag, not the tap-press-drag used on
notebook touchpads).
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Donald Arseneau as...@triumf.ca

Rich

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Mar 11, 2018, 12:01:20 AM3/11/18

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Donald Arseneau <as...@triumf.ca> wrote:
> I'm wondering if anyone has experience with Tk on a raspberry pi with
> its "Touch Display". Does it work without a lot of fuss? I won't have
> stringent demands, just button presses and dragging sliders, not multi-
> touch (but I would like touch-and-drag, not the tap-press-drag used on
> notebook touchpads).

It (Tk) works ok on Android with Androwish. Certainly button presses
and dragging sliders work just fine there. So Tk works on a touch
screen for non-stringent demands.

But, as far as I understand Androwish does have an Sdl layer that
interfaces with the Android touch screen and maps touch data back into
Tk events. I don't know if any similar 'touch interface' is present on
the pi with its 'touch display'.

Robert Heller

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Mar 11, 2018, 9:05:51 AM3/11/18

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Tcl/Tk on a Raspberry Pi is built as a standard Linux X11 application. *I* use
it with a standard display (TV monitor with HDMI) and an USB
keyboard/trackball combo device. If the touch display behaves like a standard
X11 pointer device, you could expect it to behave just like a standard X11
pointer device. I guess it would depend on the input device driver.

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Deepwoods Software -- Custom Software Services
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Joerg Honerla

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Mar 11, 2018, 10:38:21 AM3/11/18

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Am 11.03.2018 um 04:42 schrieb Donald Arseneau:
> I'm wondering if anyone has experience with Tk on a raspberry pi with
> its "Touch Display". Does it work without a lot of fuss? I won't have
> stringent demands, just button presses and dragging sliders, not multi-
> touch (but I would like touch-and-drag, not the tap-press-drag used on
> notebook touchpads).
>

Tk on a Raspberry PI (OS Linux/X11) with a touch screen works fine "out
of the box", if there is a touch driver for the screen installed. I have
tested different screen models, all work with the egtouch driver.

Joerg

--
Joerg Honerla
High Voltage Laboratory
University Duisburg-Essen
Germany
http://www.ets.uni-due.de

undro...@gmail.com

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Mar 11, 2018, 3:00:07 PM3/11/18

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Am Sonntag, 11. März 2018 06:01:20 UTC+1 schrieb Rich:

> ...

> But, as far as I understand Androwish does have an Sdl layer that
> interfaces with the Android touch screen and maps touch data back into
> Tk events. I don't know if any similar 'touch interface' is present on
> the pi with its 'touch display'.

undroidwishes are built with the same infrastructure. SDL2 on Linux uses
udev to detect evdev devices (keyboards, mice, touch screens, joysticks)
and thus could be able to support it OOTB although I have no experiences
with touch screens in this regard.

There's an experimental undroidwish for Raspberries with Debian 9 in

http://www.ch-werner.de/AndroWish/undroidwish-raspi-deb9

It contains both support for X11 and for the RPI video driver, i.e. can
run without X server in the Raspberry console, provided the user is in
the video, plugdev, and input groups.

Please let me know if and/or how this works.

chw

Donald Arseneau

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Mar 12, 2018, 9:09:53 PM3/12/18

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Joerg Honerla <joerg....@uni-due.de> writes:

> Am 11.03.2018 um 04:42 schrieb Donald Arseneau:
>> I'm wondering if anyone has experience with Tk on a raspberry pi with
>> its "Touch Display". Does it work without a lot of fuss? I won't have
>> stringent demands, just button presses and dragging sliders, not multi-
>> touch (but I would like touch-and-drag, not the tap-press-drag used on
>> notebook touchpads).
>>
>
> Tk on a Raspberry PI (OS Linux/X11) with a touch screen works fine "out of
> the box", if there is a touch driver for the screen installed. I have tested
> different screen models, all work with the egtouch driver.

Great thanks. I was hoping for that, and sort-of expecting it.

--
Donald Arseneau as...@triumf.ca

Uwe Klein

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Mar 14, 2018, 6:54:08 AM3/14/18

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Am 11.03.2018 um 04:42 schrieb Donald Arseneau:

> I'm wondering if anyone has experience with Tk on a raspberry pi with
> its "Touch Display". Does it work without a lot of fuss? I won't have
> stringent demands, just button presses and dragging sliders, not multi-
> touch (but I would like touch-and-drag, not the tap-press-drag used on
> notebook touchpads).
>

I've used Raspberries extensively. usually without a display.

But I've bought 2 display/touchscreen combos for testing.
1) a Pi3B size display that fits right on the pinheaders.
this was abit fickle to activate. but then works.

2) a HDMI display with USB touchscreen from Amazon
"Makibes 5-Zoll-Resistive Touch Screen LCD"
works right out of the box.

you may want to suppress the pointer sprite in your app.

Uwe

Donald Arseneau

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Mar 19, 2018, 6:37:41 PM3/19/18

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Thanks for that tip.

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Donald Arseneau as...@triumf.ca