UIPageController misbehaves in response to drags

Number:rdar://34926095 Date Originated:11 October 2017
Status:Open Resolved:
Product:UIKit Product Version:
Classification:UI / Usability Reproducible:Always
When a drag hovers over a UIPageController that's configured to scroll horizontally, it will randomly scroll, often into blank space.

Steps to Reproduce:
Open and run the attached project
Drag the view a little (the bug does not trigger if the page controller has never been scrolled)
Select the text in the text-field
Hold it do start a drag
Wiggle the drag over the screen for a few seconds

Expected Results:
The page-controller should not respond to the hovering drag.

Actual Results:
The page-controller rapidly scrolls by some offset - often the page width, sometimes less. This often takes it into blank space.

Xcode 9.0 (9A235)
iOS SDK 11.0


Attached project is available at https://github.com/mike-ferenduros/page-drag-test

By mike.ferenduros at Oct. 11, 2017, 3:26 a.m. (reply...)

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