Open Radar

 
The -[UIPrintInteractionController presentAnimated:completionHandler:] method does nothing in an app extension, on an iPhone, of course. The completionHandler doesn't get called sometimes. Other times it gets called with the second boolean parameter as NO/false and error equals to nil.

-[UIPrintInteractionController presentFromRect:inView:animated:completionHandler:] works just fine on an iPad.

Steps to Reproduce:
Open the attached sample project in Xcode (it was created in Xcode 6.4).

Run the ShareExtension target on the Photos app or such.

Select a photo and choose share.

Select the ShareExtension extension from the list (enable it if necessary on the More menu).

You should be presented with a simple view containing a Close button, an image view displaying the image you selected and a Print button. Press the Print button.

Expected Results:
On an iPad a popover should be presented over the Print button, containing the print options.

On an iPhone a print view controller should be presented modally.

Actual Results:
On an iPad a popover is presented over the Print button with print options, as expected.

On an iPhone nothing happens.