Cocoa Notifications

2012-10-16_09-25-28-AM_Cocoa_Notifications.m

// From: http://mobile.tutsplus.com/tutorials/iphone/ios-sdk_nsnotificationcenter/

// Add Methods to post and handle notifications
@interface ViewController ()
    - (void)postNotificationWithString:(NSString *)orientation;
    - (void)useNotificationWithString:(NSNotification*)notification;
@end

/**
 * Register for notifications.
 */
NSString *notificationName = @"MTPostNotificationTut";
[[NSNotificationCenter defaultCenter]
    addObserver:self
    selector:@selector(useNotificationWithString:)
    name:notificationName
    object:nil];

/**
 * Unregister from Notifications (ARC)
 */
- (void)dealloc {
    [[NSNotificationCenter defaultCenter] removeObserver:self];
}

/**
 * Post notification
 */
- (void)postNotificationWithString:(NSString *)orientation //post notification method and logic
{
    NSString *notificationName = @"MTPostNotificationTut";
    NSString *key = @"OrientationStringValue";
    NSDictionary *dictionary = [NSDictionary dictionaryWithObject:orientation forKey:key];
    [[NSNotificationCenter defaultCenter] postNotificationName:notificationName object:nil userInfo:dictionary];
}

/**
 * Handle notification
 */
- (void)useNotificationWithString:(NSNotification *)notification
{
    NSString *key = @"OrientationStringValue";
    NSDictionary *dictionary = [notification userInfo];
    NSString *stringValueToUse = [dictionary valueForKey:key];
    NSLog(@"Device orientation --> %@",stringValueToUse);
}