Jump when using UIRefreshControl with UIScrollView

Originator:oletha
Number:rdar://39171852 Date Originated:4/4/18
Status:Open Resolved:
Product:iOS SDK Product Version:iOS 11.2
Classification:UIKit Reproducible:Always
 
Area:
UIKit

Summary: When using a UIRefreshControl on a UIScrollView, there is a jump in the UI when you scroll the view down to initiate the 'pull to refresh' flow. This is most visible if you scroll slowly to activate the UIRefreshControl.

On the attached project, you can see the green view jump down as the UIRefreshControl activates.

Steps to Reproduce:

1. Add a UIRefreshControl to a UIScrollView with visible content
2. Slowly drag down on the scroll view until you activate the refresh control
3. Observe that the content view under your finger jumps downwards when the control activates


Expected Results:
Content inside scroll view tracks finger movement

Actual Results:
Content inside scroll view jumps down when UIRefreshControl is activated


Version/Build:
iOS 11.2

Configuration:
All devices

Comments


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