gistfile1.mm

//
// A category on UIViewController that lets you do this:
//
// [myViewController showInPopoverFromRect:someRect inView:someView];
//
// A global instance of the popover controller will be managed by the view controller..
//

#import <UIKit/UIKit.h>

@interface UIViewController (Popover) <UIPopoverControllerDelegate>

- (void)showInPopoverFromRect:(CGRect)rect inView:(UIView *)view;
- (void)showInPopoverFromBarButtonItem:(UIBarButtonItem *)item;

- (void)dismissPopover;
- (void)removePopover;

@end

static UIPopoverController *sharedPopoverController = nil;

@implementation UIViewController (Popover)

- (void)_setupSharedPopoverController
{
	[self dismissPopover];

	if (! sharedPopoverController) {
		sharedPopoverController = [[UIPopoverController alloc] initWithContentViewController:self];
	}
	else {
		sharedPopoverController.contentViewController = self;
	}

	sharedPopoverController.delegate = self;
}

- (void)showInPopoverFromRect:(CGRect)rect inView:(UIView *)view //permittedArrowDirections:(UIPopoverArrowDirection)arrowDirections
{
	[self _setupSharedPopoverController];
	[sharedPopoverController presentPopoverFromRect:rect inView:view permittedArrowDirections:UIPopoverArrowDirectionAny animated:YES];
}
	
- (void)showInPopoverFromBarButtonItem:(UIBarButtonItem *)item
{
	[self _setupSharedPopoverController];
	[sharedPopoverController presentPopoverFromBarButtonItem:item permittedArrowDirections:UIPopoverArrowDirectionUp animated:YES];
}
	
- (void)dismissPopover
{
	if (sharedPopoverController && sharedPopoverController.isPopoverVisible) {
		[sharedPopoverController dismissPopoverAnimated:YES];
		[sharedPopoverController release];
		sharedPopoverController = nil;
	}
}

- (void)removePopover
{
	if (sharedPopoverController.isPopoverVisible) {
		[sharedPopoverController dismissPopoverAnimated:NO];
		[sharedPopoverController release];
		sharedPopoverController = nil;
	}
}

- (void)popoverControllerDidDismissPopover:(UIPopoverController *)popoverController
{
	[sharedPopoverController release];
	sharedPopoverController = nil;
}