Refreshing a view from a popover - objective-c

Question

I am using Xcode 4.5 and targeting iOS 5 and above.
I have a popover that allows a user to change the background of the underlying view.
When tapping on the "button", it requires that I tap twice to see the change.
I am using NSNotification. I have tried Delegation, yet it does nothing.
Any help or tips would be greatly appreciated.
From viewWillAppear:
// nav button is for background image selection
navigationBtn.tag = buttonTag;
[navigationBtn setBackgroundImage:[UIImage imageNamed:tempImage] forState:UIControlStateNormal];
if (selectFlag) {
[navigationBtn addTarget:self action:#selector(BGSelected:) forControlEvents:UIControlEventTouchUpInside];
} else {
navigationBtn.adjustsImageWhenHighlighted = NO;
}
And the method for selection:
- (void)BGSelected:(id)sender {
self.bgtag = [sender tag];
SettingsDAO *settingsDao = [[SettingsDAO alloc] init];
if ([self.currentView isEqualToString:#"New_Journal"])
{
NSLog(#"Update Journals Background");
[settingsDao updateJournalBackgroundId:self.journalId withBackgroundId:self.bgtag];
}
// notification to let EntryView know the background has changed
[[NSNotificationCenter defaultCenter] postNotificationName:#"aBackgroundChanged"
object:self];
[settingsDao release];
}
the NSNotification Method:
- (void)aBackgroundChanged:(NSNotification *)notification {
[self invalidate];
[self reloadSettings];
}

Answer 1

If you are using storyboard, and your popover is a segue you can do like that:
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
// perform all the operations...ecc
[[(UIStoryboardPopoverSegue*)segue popoverController] setDelegate:self];
}
Then you have to make sure your caller controller has all the delegate methods.
Or, with NSNotification:
-(void)prepareForSegue:(UIStoryboardSegue *)segue sender:(id)sender {
// perform all the operations...ecc
[[NSNotificationCenter defaultCenter]
addObserver:self
selector:#selector(changeBackground:)
name:BackgroundHasChangedNotification
object:[segue destinationViewController]];
}
Then just remember to remove observer in dealloc, and in change background method:
-(void)changeBackground:(NSNotification*)notification {
NSDictionary *userInfo = notification.userInfo;
// I assume you are using background name
NSString *backgroundName = [userInfo objectForKey:BackgroundOneConstant];
// do the rest....
}