问题
Apple says:
UIModalPresentationFormSheet The width and height of the presented view are smaller than those of the screen and the view is centered on the screen. If the device is in a landscape orientation and the keyboard is visible, the position of the view is adjusted upward so that the view remains visible. All uncovered areas are dimmed to prevent the user from interacting with them.
But my view doesn't move up when the keyboard is visible. I basically want to present a textview modally above the keyboard so the user can enter text and then hit send (in a nav bar button on the presented view.)
My presenting view is a UISplitViewController (not one of its children) and I'm presenting UINavigationController who's top view controller is basically a UITextView. Rotation works, but the presented view is overlapped by the keyboard in both orientations.
I found some questions asking how to resize the presented view in this case, which is nice, but I don't want to have to make assumptions by resizing manually in the presenter or in the presented view. It seems like it should just pick a decent (undocumented) size just move it up automatically when the keyboard shows.
My presenting code looks like this:
MyViewController *vc = [[MyViewController alloc] init];
UINavigationController *nav = [[[UINavigationController alloc] initWithRootViewController:vc] autorelease];
nav.modalPresentationStyle = UIModalPresentationFormSheet;
[self.splitViewController presentModalViewController:nav animated:YES];
回答1:
As I was finishing up my question, I realized I was calling becomeFirstResponder on my UITextView in viewWillAppear. If you change it to viewDidAppear it will work, which makes sense.
来源：https://stackoverflow.com/questions/7932595/with-uipresentationformsheet-why-doesnt-my-view-move-above-the-keyboard-when-i