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Summary:

In iOS 7, we can present a modal view controller with transparency, so that the previous view controller is still visible behind it. However, rotation events are not delivered to the back view controller, only the front-most (modal) view controller.

Steps to Reproduce:

* Present a modal view controller with transparent background by specifying modalPresentationStyle of UIModalPresentationCustom and using a transitioningDelegate to specify a custom UIViewControllerAnimatedTransitioning object.
* Don't remove the source view controller so it remains visible behind the modal view controller
* Rotate the device
* The front-most (modal) view controller rotates as expected
* The back view-controller (still visible behind the transparent modal) does not rotate and does not receive any rotation event callbacks (such as -willRotateToInterfaceOrientation:duration:)

Expected Results:

Any view controllers containing views that are still on screen and visible should receive rotation events.

Actual Results:

Only the front most view controller appears to receive rotation events. A view controller with a view that is still on screen and visible behind a transparent modal view controller does not receive any rotation events.

Regression:

n/a

Notes:

A sample project to demonstrate this behaviour is attached.

Screen shots to help explain this behaviour are attached.