iOS 8 presentationController determine if really is popover

Question

I\'m using the new adaptive \"Present As Popover\" capability of iOS 8. I wired up a simple segue in the StoryBoard to do the presentation. It works great on an iPhone 6 P

Answer 1

The UIPresentationController which manages your view controller is presenting it by setting the modalPresentationStyle to UIModalPresentationPopover.

As per UIViewController reference:

presentingViewController

• The view controller that presented this view controller. (read-only)

modalPresentationStyle

• UIModalPresentationPopover: In a horizontally regular environment, a presentation style where the content is displayed in a popover view. The background content is dimmed and taps outside the popover cause the popover to be dismissed. If you do not want taps to dismiss the popover, you can assign one or more views to the passthroughViews property of the associated UIPopoverPresentationController object, which you can get from the popoverPresentationController property.

We can therefore determine whether your view controller is inside a popover or presented modally by checking the horizontalSizeClass as follows (I assumed your button is a UIBarButtonItem)

- (void)viewWillAppear:(BOOL)animated
{
    [super viewWillAppear:animated];

    if (self.presentingViewController.traitCollection.horizontalSizeClass == UIUserInterfaceSizeClassRegular)
        self.navigationItem.leftBarButtonItem = nil; // remove the button
}

The safest place to check this is in viewWillAppear: as otherwise the presentingViewController may be nil.