Programming for Touch Screens

[Michelle]

Hi, I am new it vb.net and am looking at writing for touch screens as one of
my clients wants their application written for touch screens.

I'm sure someone that done this before. Are there links I can go to to find
out what's involved, touch screen software, etc or your actual experiences
that you are willing to share, which is better than a document, I would be
most grateful.

I think it will be a fun project and would like as much information about it
before starting.

Cheers
Michelle

 

[Guest]

Just load the screen driver for the touch screen and program the Mouse Events
for the windows form to do whatever you want. You can program click, mouse
move, Mouse Down, mouse Up, etc. events. For the double click, you might
have to include a timer to distinguish between a click and double click.

 

[diego]

michelle,

the touchscreen driver/software sets the all the mouse settings
(click,double-click,right click, etc.), so all you have to do is
install the driver / software and proceed with your code as if you're
using a mouse.

diego

 

[Michelle]

Dennis / Diego

Does that mean

1) that my client doesnt have to buy actual 'touch screens' (ie: the
hardware), but instead can use software that would allow the user to still
touch a normal LCD screen and it would emulate a touch screen ; or

2) are you just saying that when developing, I can use these drivers that
come with the touch screens so that I can write events that would emulate
touching the screen?

Thanks for your quick responses.

Cheers
Michelle

 

[diego]

michelle,

your client still needs to buy a touchscreen-enabled monitor.
touchscreens are just a means of clicking whatever controls are in the
screen directly instead of having to use the mouse.

in your development, you just have to proceed as if you are using a
mouse, but also you should be aware that external keyboard
functionality will not be available, so your program will have to
provide an on-screen keyboard (like what comes with windows xp)

hth

diego

 

[Michelle]

Hi Diego

Thanks again for your information.

I have some more questions if you are open to them.

1. My client wants a touch screen and a keyboard (as there will be times
when information needs to be typed in). If they have a touch screen, they
can still have the functionality of the keyboard as well (or is this
functionality lost only when developing)?

2. You mention touchscreen-enabled monitor. Does that mean the monitor must
be a touch screen or any lcd monitor can be converted to one by use of
software?

Thanks again for your input

Michelle

 

[diego]

hi michelle,

you can still have the keyboard accessible to the users of the system.

touchscreens are specially-crafted hardware devices that have two
interfaces, one goes to the regular video card interface of your cpu
and the other goes to a serial port (i haven't seen other touchscreens
not using serial ports). although there are some high-end touchscreens
that come as a package. iow, the cpu and monitor are bundled in a
single hardware. you can see these kinds of hardware mostly in fastfood
chains and restaurants.

hth,

diego

 

[Michelle]

Hi Diego

I want to thank you for all the input you have given. It has helped me
immensely to start the road to this project.

Cheers
Michelle

 

[Homer J Simpson]

I want to thank you for all the input you have given. It has helped me
immensely to start the road to this project.

You might want to google for (touch screen wedge) before you commit.

 

[Michelle]

Hi again Diego

I feel like I'm asking really silly questions, but I have to ask them in
order to understant

My client hasn't purchased touch screens yet, they want me to write the
software and in the meantime work out the hardware they want.

That being the case, can I just download a driver for a ANY touchscreen and
play around with that or each driver is specific to the brand of
touchscreen. Do you know?

If so, where would you suggest I go to get a driver for this?

Thanks again
Michelle

 

[Jim Hubbard]

If I may interject.....

I believe what is being said here is that you should program the application
juts as you normally would using the mouse pointer to click, double-click,
select, etc. objects on the screen.

Then, when you have purchased a touchscreen LCD, the touchscreen monitor
will come with drivers that enable you to tap on the screen as well as use
the mouse to perform your application's functions. Those drivers take
screen input (touching the screen, tapping the screen, hitting it with a big
rock) and feed them to your application as though they were coming from a
mouse.

There is not special programming needed to enable the touchscreen device in
most instances. Proceed with your application (using a mouse as the input
device) and the drivers that come with the touchscreen device will interpret
screen signals as mouse inputs - making your application works the same as
it would with a mouse, without any program changes on your part.

If I missed something, somebody please speak up.

 

[Michelle]

Hi Jim

I am pleased you interjected.

Thank you for your concise information. I appreciate your summary of all so
far. It has been most valuable.

Cheers
Michelle

 

[Jim Hubbard]

It may help if you think of the touchscreen's surface as the square touchpad
surface on most laptops. The touchpad uses touch and interprets touching,
sliding your finger across it and tapping it as mouse functions. No special
program calls or functions are needed to use an application on a laptop
using a touchpad as opposed to using it on a desktop or with a real mouse.
The laptop's drivers take care of that.....just as the touchscreen monitor's
drivers will do for it.

Good luck with your project!

Jim

 

[diego]

nicely put, jim

 

[diego]

hi michelle,

programming a touchscreen-enabled application is just like programming
a mouse-enabled application. and since all (most) windows-based apps
support mouse, then there is no need for you to change anything. the
only thing that you would be considering is your a screen layout,
because you can use either your fingers or a stylus (or anything) to
click the controls on your screen, you need to make your controls a
little bigger.

as for the drivers, there are two widely used drivers (i'm sure there
are others out there): ELO and MICROTOUCH (you can do a google for the
sites). the driver that you need will depend on the hardware that your
client will purchase.

hth,

diego

 

[Guest]

Just think of the touchscreen as a laptop trackpad controlling a mouse
on the screen. Your client WILL have to buy touchscreen monitors.

 

[Dick Grier]

Hi,

My touch-screen applications have been developed just as Jim suggests. I
didn't use the actual hardware.

The only issue may be an on-screen keyboard. The one that XP provides may
not suit your needs (or it may be fine, so give it a try first). If not,
there are some ActiveX controls for this, though I do not know of any .NET
controls -- there may be some of those, too.

Dick

--
Richard Grier, MVP
Hard & Software
Author of Visual Basic Programmer's Guide to Serial Communications, Fourth
Edition,
ISBN 1-890422-28-2 (391 pages, includes CD-ROM). July 2004.
See www.hardandsoftware.net for details and contact information.

 

[Guest]

Just remember a couple of points when programming and getting a touch screen;

1) Fingers are larger than a mouse pointer so use large fonts and buttons (I
used a 12pt font on a 600/800 and it worked fine.

2) Don't buy a cheap touch screen monitor..spend the money to get a good
one. The cheaper ones continually have to be re-calibrated once or twice
daily.

 

[Michelle]

Hi Dennis and to everyone who continually adds to this thread.

That's very good information, thanks Dennis.

These newsgroups are priceless for the help that you can get. Thank you

Michelle

 

[Michelle]

Further to this post, my client wants to incorporate this into a POS (point
of sale) system

I have at the moment just one question.

Does anyone know (or have experience with) POS systems in so far as, do I
need to code the process of "opening the cash drawer" when a certain button
on the touch screen is pressed or is this an automatic process?

Much appreciated all the help so far.

Cheers
Michelle