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View Full Version : Unreliable qabstractbutton with touch screen



ksarkies
2nd May 2015, 05:08
Hi All

I have an application running on a small ARM based SBC called a TI AM335x BeagleBoneBlack with a touch screen. The setup is designed to work with simple button clicks without a mouse or keyboard; The software relies on mouse events to manage the touchscreen buttons. Everything works with the exception that pressing a button (with finger or stylus) is unreliable and requires between 1 and a dozen attempts to get the button signal to fire. The buttons change when touched to indicate that they have been activated, but the corresponding slot doesn't receive a signal. This is the case for all qabstractbutton buttons and checkboxes. Interestingly scroll bars seem to work perfectly.

Does anyone have any advice about how to improve this?

As background, I'm using QT 4.8.2 on Debian GNU/Linux 7. This is the latest version available for this particular platform.

ksarkies
4th May 2015, 09:40
Seems its due to the slow speed of the device. The UI takes a long time to respond and other asynchronous events in the background interrupt the process. Intercepting the event handler and simulating the signal-slot mechanism made some difference but the unreliability was still apparent. Oh well - just have to keep banging the screen until it responds.