Scrollview不会一直向下滚动

Question

I have a scroll view which works fine. Almost. I'm building in Any/Any. The problem is that the scroll view won't scroll past the view controller. I have a switch that is mostly in the view controller window, but the rest is off the box (not really sure how to describe it; it's in the view in the scroll view, but the view is longer than the view controller so part of it is hidden).

The scroll view will scroll down until it hits the part where the view controller would end if you were looking at it in Xcode. There is some more stuff under the switch (labels and another switch). To view these you have to forcefully scroll down. Xcode shows no constraint errors (little red circle with white arrow).

Hopefully this makes sense

Answer 1

A ScrollView needs to know the height and width of the content it is holding in order to know how much to scroll and which direction. Here is a quick read on how ScrollViews work in iOS: https://www.objc.io/issues/3-views/scroll-view/

You can set this programmatically using the contentSize property, but this requires you to know and or calculate the contentSize , which is pretty tedious in most cases.

The correct way of defining the contentSize in iOS is to define AutoLayout constraints in your View. Here is an excellent tutorial on doing just that: https://www.natashatherobot.com/ios-autolayout-scrollview/