ios - UIView inside UIView, drag to show the content -

i have view , inside have view, lower view should show top area of view, hard describe let following images talks :)

1- first case, when app launches see 2 uiview's, 1 added below other "in case lower view 1 below".

2- lets suppose put following picture image view in upper view:

3- when put image point 2 inside upper view should this:

4- , when drag upper view should expand on lower view , start showing rest of uiimageview follows:

5- , if drag in upper side of screen should following:

so, idea how achieve that?

not clear question. however, try dragging , dropping uiview libraries drop , drag uiview