Added PopoverManager.

SynthesizeSingleton.h

@@ -0,0 +1,68 @@
+//
+//  SynthesizeSingleton.h
+//  CocoaWithLove
+//
+//  Created by Matt Gallagher on 20/10/08.
+//  Copyright 2009 Matt Gallagher. All rights reserved.
+//
+//  Permission is given to use this source code file without charge in any
+//  project, commercial or otherwise, entirely at your risk, with the condition
+//  that any redistribution (in part or whole) of source code must retain
+//  this copyright and permission notice. Attribution in compiled projects is
+//  appreciated but not required.
+//
+
+#define SYNTHESIZE_SINGLETON_FOR_CLASS(classname) \
+ \
+static classname *shared##classname = nil; \
+ \
++ (classname *)shared##classname \
+{ \
+	@synchronized(self) \
+	{ \
+		if (shared##classname == nil) \
+		{ \
+			shared##classname = [[self alloc] init]; \
+		} \
+	} \
+	 \
+	return shared##classname; \
+} \
+ \
++ (id)allocWithZone:(NSZone *)zone \
+{ \
+	@synchronized(self) \
+	{ \
+		if (shared##classname == nil) \
+		{ \
+			shared##classname = [super allocWithZone:zone]; \
+			return shared##classname; \
+		} \
+	} \
+	 \
+	return nil; \
+} \
+ \
+- (id)copyWithZone:(NSZone *)zone \
+{ \
+	return self; \
+} \
+ \
+- (id)retain \
+{ \
+	return self; \
+} \
+ \
+- (NSUInteger)retainCount \
+{ \
+	return NSUIntegerMax; \
+} \
+ \
+- (void)release \
+{ \
+} \
+ \
+- (id)autorelease \
+{ \
+	return self; \
+}

UIKitUtils/PopoverManager.h

@@ -0,0 +1,24 @@
+//
+//  PopoverManager.h
+//  Lists
+//
+//  Created by Marcel Ruegenberg on 25.02.11.
+//  Copyright 2011 Dustlab. All rights reserved.
+//
+
+#import <Foundation/Foundation.h>
+
+/** 
+ A class for managing the retaining of popovers in a central place.
+
+ Because even though Apple basically tells you to have only one popover at a time, they make it surprisingly hard to do this properly.
+ */
+@interface PopoverManager : NSObject {
+	UIPopoverController *currentPopoverController;
+}
+
+@property (nonatomic, retain) UIPopoverController *currentPopoverController;
+
++ (PopoverManager *)sharedPopoverManager;
+
+@end

UIKitUtils/PopoverManager.m

@@ -0,0 +1,50 @@
+//
+//  PopoverManager.m
+//  Lists
+//
+//  Created by Marcel Ruegenberg on 25.02.11.
+//  Copyright 2011 Dustlab. All rights reserved.
+//
+
+#import "PopoverManager.h"
+#import "SynthesizeSingleton.h"
+
+@implementation PopoverManager
+@synthesize currentPopoverController;
+
+SYNTHESIZE_SINGLETON_FOR_CLASS(PopoverManager);
+
+- (id)init {
+	if((self = [super init])) {
+		[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(didReceiveMemoryWarning:) name:UIApplicationDidReceiveMemoryWarningNotification object:nil];
+	}
+	return self;
+}
+
+- (void)setCurrentPopoverController:(UIPopoverController *)thePopoverController {
+	if(thePopoverController != currentPopoverController) {
+		if(currentPopoverController && currentPopoverController.popoverVisible) {
+#ifndef NDEBUG
+			NSLog(@"Warning: New popover being set in PopoverManager while existing popover is still visible.");
+#endif
+			[currentPopoverController dismissPopoverAnimated:NO]; // no animation when dismissing because this should not happen
+		}
+		[currentPopoverController release];
+		currentPopoverController = [thePopoverController retain];
+	}
+}
+
+- (void)didReceiveMemoryWarning:(NSNotification *)notification {
+	if(self.currentPopoverController && ! self.currentPopoverController.popoverVisible) {
+		self.currentPopoverController = nil;
+	}
+}
+
+- (void) dealloc
+{
+	self.currentPopoverController = nil;
+	[super dealloc];
+}
+
+
+@end