ios - Make Top image in UIScrollView enlarge on scroll view bounds? -

i have uiscroll view uiview inside content view. layout is:

self.scrollview = uiscrollview() self.view.addsubview(self.scrollview) self.scrollview.backgroundcolor = uicolor.yellowcolor()  // pin edges edges of superview (self.view) self.scrollview.snp_makeconstraints { (make) -> void in   make.edges.equalto(self.view) }  // create contentview self.contentview = uiview() self.contentview.backgroundcolor = uicolor.redcolor() self.scrollview.addsubview(self.contentview)  // pin edges of contentview scrollview self.contentview.snp_makeconstraints { (make) -> void in   make.edges.equalto(self.scrollview)  } 

in contentview have uiimageview @ top , uilabels below:

let imageview = uiimageview(...) let labe1 = uilabel(...) let labe2 = uilabel(...) self.contentview.addsubview(imageview) self.contentview.addsubview(labe1) self.contentview.addsubview(labe2) 

here how looks like:

when pull down scroll view scroll view bounces @ top. want image enlarges when scroll view bounces.

i did uiscrollviewdelegate:

   func scrollviewdidscroll(scrollview: uiscrollview) {     let offsety: cgfloat = scrollview.contentoffset.y     if offsety < -64 {       let progress:cgfloat = fabs(offsety + 64) / 100       self.imageview.transform = cgaffinetransformmakescale(1 + progress, 1 + progress)     }   } 

this works problem when image transformed should not overlay border red area contains labels. here happens when bounce:

i want image still enlarges not overlapping border red area. how can that?

i suggest resize whole uiscrollview pager view - don't forget reset its's frame prevent wrong paging.