Local Notification Sample Code (OS 4.0 only)

Start a new Window-based Application Project called LocalPush

Add an instance variable bgTask in LocalPushAppDelegate


@interface LocalPushAppDelegate : NSObject {
    UIWindow *window;
    UIBackgroundTaskIdentifier bgTask;
}


It will fire up a Local Notification to remind you one min before the event which is 2 minutes due from now

LocalPushAppDelegate.m Select all


//
// LocalPushAppDelegate.m
// LocalPush
//

@interface ToDoItem : NSObject {
NSInteger year;
NSInteger month;
NSInteger day;
NSInteger hour;
NSInteger minute;
NSInteger second;
NSString *eventName;
}

@property (nonatomic, readwrite) NSInteger year;
@property (nonatomic, readwrite) NSInteger month;
@property (nonatomic, readwrite) NSInteger day;
@property (nonatomic, readwrite) NSInteger hour;
@property (nonatomic, readwrite) NSInteger minute;
@property (nonatomic, readwrite) NSInteger second;
@property (nonatomic, copy) NSString *eventName;

@end

@implementation ToDoItem

@synthesize year, month, day, hour, minute, second, eventName;

@end

#import "LocalPushAppDelegate.h"

@implementation LocalPushAppDelegate

@synthesize window;

#define ToDoItemKey @"EVENTKEY1"
#define MessageTitleKey @"MSGKEY1"


- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
NSLog(@"application: didFinishLaunchingWithOptions:");
// Override point for customization after application launch

UILocalNotification *localNotif = [launchOptions
objectForKey:UIApplicationLaunchOptionsLocalNotificationKey];

if (localNotif) {
NSString *itemName = [localNotif.userInfo objectForKey:ToDoItemKey];
// [viewController displayItem:itemName]; // custom method
application.applicationIconBadgeNumber = localNotif.applicationIconBadgeNumber-1;
NSLog(@"has localNotif %@",itemName);
}
else {
[[UIApplication sharedApplication] cancelAllLocalNotifications];
NSDate *now = [NSDate date];
NSLog(@"now is %@",now);
NSDate *scheduled = [now dateByAddingTimeInterval:120] ; //get x minute after
NSCalendar *calendar = [NSCalendar currentCalendar];

unsigned int unitFlags = NSYearCalendarUnit|NSMonthCalendarUnit|NSDayCalendarUnit|NSHourCalendarUnit|NSMinuteCalendarUnit;
NSDateComponents *comp = [calendar components:unitFlags fromDate:scheduled];

NSLog(@"scheduled is %@",scheduled);

ToDoItem *todoitem = [[ToDoItem alloc] init];

todoitem.day = [comp day];
todoitem.month = [comp month];
todoitem.year = [comp year];
todoitem.hour = [comp hour];
todoitem.minute = [comp minute];
todoitem.eventName = @"Testing Event";

[self scheduleNotificationWithItem:todoitem interval:1];
NSLog(@"scheduleNotificationWithItem");
}
[window makeKeyAndVisible];
return YES;
}

- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notif {
NSLog(@"application: didReceiveLocalNotification:");
NSString *itemName = [notif.userInfo objectForKey:ToDoItemKey];
NSString *messageTitle = [notif.userInfo objectForKey:MessageTitleKey];
// [viewController displayItem:itemName]; // custom method
[self _showAlert:itemName withTitle:messageTitle];
NSLog(@"Receive Local Notification while the app is still running...");
NSLog(@"current notification is %@",notif);
application.applicationIconBadgeNumber = notif.applicationIconBadgeNumber-1;

}

- (void) _showAlert:(NSString*)pushmessage withTitle:(NSString*)title
{

UIAlertView* alertView = [[UIAlertView alloc] initWithTitle:title message:pushmessage delegate:self cancelButtonTitle:@"OK" otherButtonTitles:nil];
[alertView show];
if (alertView) {
[alertView release];
}
}


- (void)scheduleNotificationWithItem:(ToDoItem *)item interval:(int)minutesBefore {
NSCalendar *calendar = [NSCalendar autoupdatingCurrentCalendar];
NSDateComponents *dateComps = [[NSDateComponents alloc] init];
[dateComps setDay:item.day];
[dateComps setMonth:item.month];
[dateComps setYear:item.year];
[dateComps setHour:item.hour];
[dateComps setMinute:item.minute];
NSDate *itemDate = [calendar dateFromComponents:dateComps];
[dateComps release];


UILocalNotification *localNotif = [[UILocalNotification alloc] init];
if (localNotif == nil)
return;
localNotif.fireDate = [itemDate dateByAddingTimeInterval:-(minutesBefore*60)];
NSLog(@"fireDate is %@",localNotif.fireDate);
localNotif.timeZone = [NSTimeZone defaultTimeZone];

localNotif.alertBody = [NSString stringWithFormat:NSLocalizedString(@"%@ in %i minutes.", nil),
item.eventName, minutesBefore];
localNotif.alertAction = NSLocalizedString(@"View Details", nil);

localNotif.soundName = UILocalNotificationDefaultSoundName;
localNotif.applicationIconBadgeNumber = 1;
// NSDictionary *infoDict = [NSDictionary dictionaryWithObject:item.eventName forKey:ToDoItemKey];
NSDictionary *infoDict = [NSDictionary dictionaryWithObjectsAndKeys:item.eventName,ToDoItemKey, @"Local Push received while running", MessageTitleKey, nil];
localNotif.userInfo = infoDict;

[[UIApplication sharedApplication] scheduleLocalNotification:localNotif];
NSLog(@"scheduledLocalNotifications are %@", [[UIApplication sharedApplication] scheduledLocalNotifications]);
[localNotif release];
}

- (NSString *) checkForIncomingChat {
return @"javacom";
};

- (void)applicationDidEnterBackground:(UIApplication *)application {
NSLog(@"Application entered background state.");
// UIBackgroundTaskIdentifier bgTask is instance variable
// UIInvalidBackgroundTask has been renamed to UIBackgroundTaskInvalid
NSAssert(self->bgTask == UIBackgroundTaskInvalid, nil);

bgTask = [application beginBackgroundTaskWithExpirationHandler: ^{
dispatch_async(dispatch_get_main_queue(), ^{
[application endBackgroundTask:self->bgTask];
self->bgTask = UIBackgroundTaskInvalid;
});
}];

dispatch_async(dispatch_get_main_queue(), ^{
while ([application backgroundTimeRemaining] > 1.0) {
NSString *friend = [self checkForIncomingChat];
if (friend) {
UILocalNotification *localNotif = [[UILocalNotification alloc] init];
if (localNotif) {
localNotif.alertBody = [NSString stringWithFormat:
NSLocalizedString(@"%@ has a message for you.", nil), friend];
localNotif.alertAction = NSLocalizedString(@"Read Msg", nil);
localNotif.soundName = @"alarmsound.caf";
localNotif.applicationIconBadgeNumber = 1;
NSDictionary *infoDict = [NSDictionary dictionaryWithObjectsAndKeys:@"Your Background Task works",ToDoItemKey, @"Message from javacom", MessageTitleKey, nil];
localNotif.userInfo = infoDict;
[application presentLocalNotificationNow:localNotif];
[localNotif release];
friend = nil;
break;
}
}
}
[application endBackgroundTask:self->bgTask];
self->bgTask = UIBackgroundTaskInvalid;
});
}


- (void)dealloc {
[window release];
[super dealloc];
}


@end


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