iOS上(shàng)有兩種消息通知，一種是(shì)本地(dì / de)消息（Local Notification），一種是(shì)遠程消息(Push Notification，也(yě)叫Remote Notification)，設計這(zhè)兩種通知的(de)目的(de)都是(shì)爲(wéi / wèi)了(le／liǎo)提醒用戶，現在(zài)有些什麽新鮮的(de)事情發生了(le／liǎo)，吸引用戶重新打開應用。本地(dì / de)推送也(yě)可以(yǐ)通過服務器控制，比如說(shuō)如果有新消息了(le／liǎo)，推送消息，但是(shì)，前提是(shì)程序必須是(shì)打開的(de)，而(ér)遠程推送，是(shì)通過蘋果APNS服務器，推送給手機，手機在(zài)推送給具體的(de)哪個(gè)程序，一般遠程推送用到(dào)的(de)比較多，先介紹下本地(dì / de)推送，下節在(zài)介紹遠程推送。
本地(dì / de)推送：
首先，先在(zài)appdelegate中注冊：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {

    [application registerUserNotificationSettings:[UIUserNotificationSettings settingsForTypes:UIUserNotificationTypeAlert|UIUserNotificationTypeBadge|UIUserNotificationTypeSound categories:nil]];//注冊本地(dì / de)推送
    
    // Override point for customization after application launch.
    return YES;
}

然後，在(zài)具體的(de)viewcontroller中實現推送：

- (IBAction)localPushNow:(id)sender {
 
    dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_DEFAULT, 0), ^{
        //本地(dì / de)推送
        UILocalNotification*notification = [[UILocalNotification alloc]init];
        NSDate * pushDate = [NSDate dateWithTimeIntervalSinceNow:10];
        if (notification != nil) {
            notification.fireDate = pushDate;
            notification.timeZone = [NSTimeZone defaultTimeZone];
            notification.repeatInterval = kCFCalendarUnitDay;
            notification.soundName = UILocalNotificationDefaultSoundName;
            notification.alertBody = @"hello，world";
            notification.applicationIconBadgeNumber = 0;
            NSDictionary*info = [NSDictionary dictionaryWithObject:@"test" forKey:@"name"];
            notification.userInfo = info;
            [[UIApplication sharedApplication] scheduleLocalNotification:notification];
            
        }
    });

}

在(zài)appdelegate中會接收到(dào)推送信息：

//接收本地(dì / de)推送

//接收本地(dì / de)推送
- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification{
    NSLog(@"%@",notification.alertBody);
    UILabel*label = [[UILabel alloc]init];
    label.frame = CGRectMake(0, 0, 160, 20);
    label.layer.cornerRadius = 10;
    label.backgroundColor = [UIColor blackColor];
    label.text = notification.alertBody;
    label.textColor = [UIColor whiteColor];
    label.font = [UIFont systemFontOfSize:12];
    label.textAlignment = NSTextAlignmentCenter;
    
    [self.window addSubview:label];
}

過程中可能會出(chū)現如下狀況：
Attempting to schedule a local notification……with a sound but haven't received permission from the user to play sounds
Attempting to schedule a local notification……with an alert but haven't received permission from the user to display alerts
可能是(shì)因爲(wéi / wèi)你沒有注冊，或者設置中沒有開啓推送功能，