InputView: ViewController's view is dropped from view hierarchy when resizing multitasking panes

Number:rdar://34131904 Date Originated:8/29/2017
Status:Open Resolved:
Product:iOS Product Version:10.3.3
Classification: Reproducible:Yes

On the 9.7" & 10.5" iPad, using a VC's view as an input view, the view is dropped/moved from the view hierarchy after resizing multitasking panes. If using a UIView that is not owned by a VC, the input view works as expected.

Note: this issue does _not_ happen on the 12" iPad's. 
Project demonstrating bug is here:

Steps to Reproduce:
Test this on the iPad 9.7" or 10.5" device/sim:

1) Instantiate a UIViewController and assign it's view as the inputView on a UITextField.
2) During runtime tap the text field so it becomes 1st responder. InputView will appear as expected.
3) Swipe in a secondary app pane and anchor it. Input view will disappear and reappear (expected). When the input view reappears here, the VC's view is not in the view hierarchy.

Alternative Flow:
1) Already In multitasking mode, tap the textfield again. Input view appears as expected. 
2) Resize the multitasking panes. Input view will disappear and reappear (expected).
3) When the input view reappears here, the VC's view is not in the view hierarchy.

Expected Results:
The VC's view should not be dropped from the view hierarchy after any multitasking user activity.

Observed Results:
The VC's view is no longer in the view hierarchy. The keyboard displays an empty grey rect.

iOS 10.3.3 and iOS 11 Beta 7

Demo project is located here: (also attaching it to this bug report).

Device and Sim (7.9", 9.7", and 10.5" iPads only). This issue does NOT occur on 12.9" iPads. In addition, I tested this on iOS 11 Beta 7 and saw similar issues.


Follow up response to Apple

Followed up with Apple after a request to test this issue on the latest iOS11 Beta:

"Tested with iOS 11 Beta 10 on two different devices:

  • Issue was reproduced on a 10.5" iPad Pro
  • Issue was not present on the 12.9" iPad Pro (as originally reported)

I am attaching sysdiagnose from the 10.5" iPad."

By matt.bumgardner at Sept. 8, 2017, 1:22 p.m. (reply...)

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