IOS storyboard uiview and uiscrollview position -

i created uiviewcontroller in storyboard , hierarchy follows :

--uiview

---uiview (iboutlet -> scrollcontentview)

----uilabel

----uilabel

....

in class function viewdidload:

[_scrollcontentview removefromsuperview];  uiscrollview *scrollview = [[uiscrollview alloc] initwithframe:self.view.frame]; [self.view addsubview:scrollview];  [scrollview addsubview:_scrollcontentview]; [scrollview setcontentsize:_scrollcontentview.size]; [scrollview setdelegate:self]; 

run it, coordinates of starting point in middle of display screen _scrollcontentview.

print _scrollcontentview point (0,0), why it's position wrong?

i test add new uilabel scrollview, label's point (0,0), it's not iboutlet, it's display normal.