Bugs of Screen Edge System Gesture Deferring

Originator:an00na
Number:rdar://33631539 Date Originated:July 31 2017, 2:50 PM
Status:Closed Resolved:in iOS 11 GM
Product:iOS + SDK Product Version:11 beta 4
Classification:UI/Usability Reproducible:Always
 
Area:
UIKit

Summary:
1. If Screen Edge System Gestures are not deferred(by default), for a full screen view controller(prefersStatusBarHidden returns true), top edge system gesture still delivers touch events to view's pan gestures. It causes garbage drawing in drawing apps while user is pulling down today/notification center.
2. On iPad, if Screen Edge System Gestures are deferred(by overriding preferredScreenEdgesDeferringSystemGestures), the first bottom edge system gesture doesn't show upward tongue at the bottom so no visual clue to users what's happening.

Steps to Reproduce:
1. Launch sample app on either iPhone or iPad.
2. Try pulling down today/notification center from the top edge.
3. Read console logs to see that view's pan gesture is still firing.
4. Uncomment preferredScreenEdgesDeferringSystemGestures override in ViewController.swift.
5. Launch sample app on iPad.
6. Try pulling up dock from the bottom edge.
7. See there is no upward tongue at the bottom.

Code: https://mega.nz/#!4TwzmbLb!N7rAkCRKyclMBQdtvufNgPKjeWuKTPpDKfOIOR4z_io

Comments


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