ios - Constraints/AutoLayout in Interface Builder results in White Bar -

i developing ios application in xcode using swift , having difficulties 'actual' results of designs when using constraints.

currently constraints set uiimageview has equal width , height of superview (as fill screen). seen in screenshot below iphone 5s, there white bar @ bottom approx. 60 pixels in height not in source image.

further possibly relevant info:

• uses regular uiviewcontroller
• only other constraints centering in x , y
• uiviewcontroller subclassed use custom font
• removing coloured bar @ top not remove white line
• on storyboard, there no white line iphone size

i've tried can think of , scoured stackoverflow, please help!

if you're view controller embedded in navigation controller, toolbar, not controlled uiviewcontroller rather containing view controller. in case this:

in parent view controller:

override func prepareforsegue(segue: uistoryboardsegue, sender: anyobject?) {     let destinationvc = segue.destinationviewcontroller as! destinationviewcontroller     destinationvc.hidesbottombarwhenpushed = true } 

in child view controller

class destinationvc: uiviewcontroller {     override func viewdidload() {         self.navigationcontroller?.settoolbarhidden(true, animated: false)     } } 

if isn't toolbar that's causing issue, there ways debug this. when run issue this, using xcode's view debugger. when run app in simulator, navigate view that's causing issue. then, within xcode, go "debug" > "view debugging" > "capture view hierarchy". freeze app , snapshot view being shown in simulator. can use mouse hover on various elements , views see , how they're connected assist in shedding insight problem occurring within views/code. hope helps.