51354714: Presenting a UIAlertController over a modally presented UIViewController does not correctly update the tintAdjustmentMode of the view controller

[openradar-mirror]

Description

Area:
UIKit

Summary:

When a view controller presents a UIAlertController, the view controller's view ordinarily dims any controls (buttons, etc) via the tintAdjustmentMode being set to .dimmed.

If the view controller has been modally presented, this does not happen.

Steps to Reproduce:

1. Present a view controller modally. The view controller should include some tinted control, for example a button.
2. Present a UIAlertController from the modally presented view controller.

Expected Results:

The button is dimmed when the alert controller is presented.

Actual Results:

The button is not dimmed.

Version/Build:

iOS 12.3.1, Xcode 10

Product Version: 12.3.1
Created: 2019-06-03T14:07:05.031818
Originated: 2019-06-03T00:00:00
Open Radar Link: http://www.openradar.me/51354714