使用 EKEventEditViewController 创建带有闹钟的日历事件

Question

我使用以下代码创建一个事件，并显示一个弹出窗口，要求用户保存该事件：

EKEventStore *eventStore = [[EKEventStore alloc] init];
EKCalendar *calendar = [eventStore defaultCalendarForNewEvents];
EKEvent *event = [EKEvent eventWithEventStore:eventStore];
event.calendar = calendar;
event.title = [NSString stringWithFormat:@"Event: %@", [self.event title]]; 
event.location = self.event.location;
event.notes = [self stringByStrippingHTML: [self.event description]];
event.startDate = [self.event startDate]; 
event.endDate = [self.event endDate];

NSTimeInterval alarmOffset = -1*60*60;//1 hour
EKAlarm *alarm = [EKAlarm alarmWithRelativeOffset:alarmOffset];

[event addAlarm:alarm];
EKEventEditViewController *eventViewController = [[EKEventEditViewController alloc] init];
eventViewController.event = event;
eventViewController.eventStore=eventStore;
eventViewController.editViewDelegate = self;
[self.navigationController presentModalViewController:eventViewController animated:YES];

这工作正常，只是事件警报属性没有设置，如下图所示：

如果我在显示视图控制器之前保存事件，它确实会设置警报。

请注意我使用的是 LLVM 编译器，所以不用担心无法发布东西！

塔罗斯

​

Answer 1

终于知道怎么做了。

您的控制器必须实现 UINavigationControllerDelegate 协议，并将 EKEventEditViewController 委托设置为 self。然后只需实现

navigationController:(UINavigationController *)navigationController willShowViewController:(UIViewController *)viewControllerAnimated:(BOOL)animated

方法并在那里添加警报。

这是我的实现。

- (void)navigationController:(UINavigationController *)navigationController 
  willShowViewController:(UIViewController *)viewController animated:(BOOL)animated {

    if ([navigationController isKindOfClass:[EKEventEditViewController class]]) {
      EKEventEditViewController *ek = (EKEventEditViewController*)navigationController;
      EKEvent *event = ek.event;
      // set alarm to 15 mins prior of the event if it starts later than 15 mins out
      if ([event.startDate compare:[[NSDate date] dateByAddingTimeInterval:60*15]] != NSOrderedAscending) { 
        EKAlarm *alarm = [EKAlarm alarmWithRelativeOffset:60*15*-1];
        event.alarms = [NSArray arrayWithObject:alarm];
      }    
    }
}

Answer 2

NSTimeInterval alarmOffset = -1*60*60;//1 hour
EKAlarm *alarm = [EKAlarm alarmWithRelativeOffset:alarmOffset];

[event addAlarm:alarm];

在呈现控制器之后编写上面的代码，即在该行之后

[self.navigationController presentModalViewController:eventViewController animated:YES];