I am new to Qt programming, and also new to creating a forum. So bear with me if I miss any detail. Thanks.
I have recently started working GUI apps for BeagleBone Black using Qt using Qt Creator on Ubuntu 14.04. I have setup cross-compiler environment using following link:

The cross-compiler is working fine. The only problem is that when I run the built app on beaglebone's Debian Desktop it does not show any GUI window. Output window is only coming on HDMI based display.

I believe there is any issue with display selection in some configuration as I get following message on console output on Qt-creator when I stop the application.
bash: line 1: 1559 Aborted DISPLAY=:0.0 /home/Debian/Desktop/App_Name -qws

Your help and support is appreciated.