在iOS8之後，以前的本地推送寫法可能會出錯，接收不到推送的資訊，

如果出現以下資訊：

1 Attempting to schedule a local notification
2 with an alert but haven't received permission from the user to display alerts
3 with a sound but haven't received permission from the user to play sounds

// Registering UIUserNotificationSettings more than once results in previous settings being overwritten.
- (void)registerUserNotificationSettings:(UIUserNotificationSettings *)notificationSettings NS_AVAILABLE_IOS(8_0);
 

第一步：註冊本地通知：

// 設定本地通知
+ (void)registerLocalNotification:(NSInteger)alertTime {
  UILocalNotification *notification = [[UILocalNotification alloc] init];
  // 設定觸發通知的時間
  NSDate *fireDate = [NSDate dateWithTimeIntervalSinceNow:alertTime];
  NSLog(@"fireDate=%@",fireDate);
  
  notification.fireDate = fireDate;
  // 時區
  notification.timeZone = [NSTimeZone defaultTimeZone];
  // 設定重複的間隔
  notification.repeatInterval = kCFCalendarUnitSecond;
  
  // 通知內容
  notification.alertBody =  @"該起床了...";
  notification.applicationIconBadgeNumber = 1;
  // 通知被觸發時播放的聲音
  notification.soundName = UILocalNotificationDefaultSoundName;
  // 通知引數
  NSDictionary *userDict = [NSDictionary dictionaryWithObject:@"開始學習iOS開發了" forKey:@"key"];
  notification.userInfo = userDict;
  
  // ios8後，需要新增這個註冊，才能得到授權
  if ([[UIApplication sharedApplication] respondsToSelector:@selector(registerUserNotificationSettings:)]) {
    UIUserNotificationType type =  UIUserNotificationTypeAlert | UIUserNotificationTypeBadge | UIUserNotificationTypeSound;
    UIUserNotificationSettings *settings = [UIUserNotificationSettings settingsForTypes:type
                                                                             categories:nil];
    [[UIApplication sharedApplication] registerUserNotificationSettings:settings];
    // 通知重複提示的單位，可以是天、周、月
    notification.repeatInterval = NSCalendarUnitDay;
  } else {
    // 通知重複提示的單位，可以是天、周、月
    notification.repeatInterval = NSDayCalendarUnit;
  }
  
  // 執行通知註冊
  [[UIApplication sharedApplication] scheduleLocalNotification:notification];
}
 

// 本地通知回撥函式，當應用程式在前臺時呼叫
- (void)application:(UIApplication *)application didReceiveLocalNotification:(UILocalNotification *)notification {
  NSLog(@"noti:%@",notification);
  
  // 這裡真實需要處理互動的地方
  // 獲取通知所帶的資料
  NSString *notMess = [notification.userInfo objectForKey:@"key"];
  UIAlertView *alert = [[UIAlertView alloc] initWithTitle:@"本地通知(前臺)"
                                                  message:notMess
                                                 delegate:nil
                                        cancelButtonTitle:@"OK"
                                        otherButtonTitles:nil];
  [alert show];
  
  // 更新顯示的徽章個數
  NSInteger badge = [UIApplication sharedApplication].applicationIconBadgeNumber;
  badge--;
  badge = badge >= 0 ? badge : 0;
  [UIApplication sharedApplication].applicationIconBadgeNumber = badge;
  
  // 在不需要再推送時，可以取消推送
  [HomeViewController cancelLocalNotificationWithKey:@"key"];
}
 

// 取消某個本地推送通知
+ (void)cancelLocalNotificationWithKey:(NSString *)key {
  // 獲取所有本地通知陣列
  NSArray *localNotifications = [UIApplication sharedApplication].scheduledLocalNotifications;
  
  for (UILocalNotification *notification in localNotifications) {
    NSDictionary *userInfo = notification.userInfo;
    if (userInfo) {
      // 根據設定通知引數時指定的key來獲取通知引數
      NSString *info = userInfo[key];
      
      // 如果找到需要取消的通知，則取消
      if (info != nil) {
        [[UIApplication sharedApplication] cancelLocalNotification:notification];
        break;
      }
    }
  }
}