iPad modal form sheet takes up the whole screen an

问题:

I'm trying to create a form sheet modal on iPad, which should be a 540x620 modal view.

I've created a view controller with a NIB file whose view is a 540x620 sized UIView (with stuff on it).

I set the modal presentation style to UIModalPresentationFormSheet, and call presentModalViewController:animated: on the current view controller.

My view slides in from the bottom, but instead of being a form sheet, it takes up the whole screen (my view elements are all anchored in the top left of the screen).

Even stranger, when I dismiss it, all the UI that was "underneath" it, is all re-layed out to be in the center, in approximately a form sheet sized area in the center of the screen. Bizarro!

Anyone have any suggestions as to what could cause this behavior?

Thanks.

回答1:

Figured this out. I was setting the modal presentation style on the parent view controller-- it needs to be set on the newly-created child controller. One needs to think of it as a property of the child, not something the parent controls.

I would delete this question, but figure I'll leave it as a signpost for the future wayward.