I compile the qt-embedded for gumstix , I also install the x11,but I can not run my program without -qws

but when I run my program  with -qws,  the screen become green, and I found there are two cursors appear, black one for linux system, and the white one for qt program.  

when I move, both cursor will move, and the screen seems not able to refresh. when move the cursor,  the other icon on desktop will appear. 

I was stucked by this problem for one week, still can not figure out how to fix that

Is anyone has idea about this problem?

Thank you so much

Best regards