[beaglebone black] vnc viewer issue

hi all
I use angtorm 3.8.13 and use vnc viewer
I got some problems with vnc viewer when i want to see my ran opencv code
i have built the opencv samples from opencv-2.4.3 and some other opencv code
i can run the opencv code like in the picture that i attached (opencv sample “squares”) (i used command : ./squares)
after the opencv code ran: a new window that show the sample appeared in back of terminal window
the problem is : I cannot even move the terminal window and the sample squares window so i cannnot see the sample code.
the only option left after i ran the code just to close the terminal window

please help me
what should i do?
thanks all

help me please. I’m still stuck here
I can’t switch from terminal window to running project window

nohup ./squares &