[Interest] touch functionality not working with my Qt 5 apps

[Rutledge Shawn]

On 12 Apr 2013, at 5:20 PM, fsjunior wrote:

> VStevenP <vstevenpavao <at> yahoo.com> writes:
> 
>> 
>> I am trying to figure out why the touch functionality of my LG display 
> isn't working with my Qt 5 apps.
>> 
>> The touch technology is an N-trig DuoSense which is easily auto-detected 
> and added as a USB input device by
>> Angstrom 2011.03 (kernel 2.6.32) on my BeagleBoard-xM.
>> 
>> (Note that kernel 2.6.31 and greater has mainline support for N-trig, and 
> that Angstrom 2011.03 is
>> configured with CONFIG_HID_NTRIG=y, which allows the touch functionality 
> to work with Angstrom).
>> 
>> However, when I run my Qt 5 apps on the BeagleBoard-xM, touching the 
> display doesn't result in cursor
>> control, and swipe gestures do nothing.  The mouse works fine, however.
>> 
>> Shouldn't the touch functionality work automatically in this situation? 
>  Note that the the touch
>> functionality provided by the N-trig DuoSense can actually successfully 
> control the mouse on my MacBook
>> Pro if I simply plug it into it via USB.  I can make selections in apps, 
> etc.
>> 
>> I'm hoping there's something obvious I'm missing, because this combination 
> of technologies should work,
>> from what I understand.
>> 
> 
> 
> Hi VStevenP,
> 
> I am having the "same" problem. I use Angstrom 2011.03 and kernel 2.6.32. 
> But in my case even the tslib test software get any position event.
> 
> Do you have any advance in your problem?

Are you running X?  If you are referring to multi-point touch, do you have XInput 2.2 protocol (which for now probably means libXi version 1.6)?  Qt 5 relies on that to "just work" with X11, but it's kindof new, so might not be installed.  Otherwise you can try using the evdevtouch plugin, which reads from /dev/inputX and provides events to Qt without going through the X11 event queue.  Check qtbase/src/plugins/generic/evdevtouch/README for more info.