我无法验证用户日历上是否已存在某个事件。我需要检查它以确定是否应该添加它,以便不创建重复的日历条目。现在,每次运行代码时,我都会创建一个重复条目。
首先,这是我创建日历条目的方式:
+ (NSString *) addEventToCalenderWithDate : (NSDate *) eventDate
eventTitle : (NSString *) eventTitle
eventLocation : (NSString *) eventLocation
allDayEvent : (BOOL) isAllDay
{
EKEventStore *store = [[EKEventStore alloc] init];
[store requestAccessToEntityType:EKEntityTypeEvent completion:^(BOOL granted, NSError *error) {
if (!granted) {
returnValue = @"calendar error";
}
else if ([self eventExists:dateAndTime eventTitle:eventTitle allDayEvent:isAllDay]) {
returnValue = @"duplicate";
}
else {
EKEvent *event = [EKEvent eventWithEventStore:store];
event.title = eventTitle;
event.startDate = dateAndTime;
if (eventTimeString == (id)[NSNull null] || eventTimeString.length == 0 || isAllDay) {
event.allDay = YES;
event.endDate = dateAndTime;
} else {
event.endDate = [event.startDate dateByAddingTimeInterval:60*60]; //set 1 hour meeting
}
event.location = eventLocation;
[event setCalendar:[store defaultCalendarForNewEvents]];
NSError *err = nil;
[store saveEvent:event span:EKSpanThisEvent commit:YES error:&err];
returnValue = @"success";
}
}];
return returnValue;
}
这样可以正确设置事件。但是,如果我再次运行它,我希望else if子句将返回
YES
,并且不会创建任何新条目。但是,它总是返回NO
,并且每次执行时我都会创建一个新的日历条目。这是该方法:+ (BOOL) eventExists : (NSDate *) date
eventTitle : (NSString *) eventTitle
allDayEvent : (BOOL) isAllDay
{
EKEventStore *store = [[EKEventStore alloc] init];
NSPredicate *predicateForEventOnDate = [[NSPredicate alloc] init];
if (isAllDay)
predicateForEventOnDate = [store predicateForEventsWithStartDate:date endDate:date calendars:nil]; // nil will search through all calendars
else
predicateForEventOnDate = [store predicateForEventsWithStartDate:date endDate:[date dateByAddingTimeInterval:60*60] calendars:nil]; // nil will search through all calendars
NSArray *eventOnDate = [store eventsMatchingPredicate:predicateForEventOnDate];
NSLog(@"eventOnDate: %@", eventOnDate);
BOOL eventExists = NO;
for (EKEvent *eventToCheck in eventOnDate) {
if ([eventToCheck.title isEqualToString:eventTitle]) {
eventExists = YES;
}
}
return eventExists;
}
在逐步执行此方法时,我注意到称为
NSArray
的eventOnDate
是nil
(EKEventStore
不是nil
)。我不知道这是否意味着它根本没有找到任何匹配的事件,或者是否正在发生其他事情。我做错了什么,因此无法识别日历中的现有事件?谢谢!
最佳答案
问题似乎出在您为谓词选择的日期范围内。
predicateForEventOnDate = [store predicateForEventsWithStartDate:date endDate:date calendars:nil];
因为谓词查询的开始日期和结束日期相同,所以它将查找“0”秒范围内的事件。
predicateForEventOnDate = [store predicateForEventsWithStartDate:date endDate:[date dateByAddingTimeInterval:60*60] calendars:nil];
这只会查找提供日期后一个小时内的事件。
NSCalendar *const calendar = NSCalendar.currentCalendar;
NSCalendarUnit const preservedComponents = (NSCalendarUnitYear | NSCalendarUnitMonth | NSCalendarUnitDay);
//strip away hours, minutes and seconds to find date - at start of day
NSDateComponents *startComponents = [calendar components:preservedComponents fromDate:self.date];
//set finished date to 1 full day later
NSDateComponents *offset = [[NSDateComponents alloc] init];
[offset setDay:1];
NSDate *start = [calendar dateFromComponents:startComponents];
NSDate *finish = [calendar dateByAddingComponents:offset toDate:self.date options:0];
NSPredicate *predicateForEventOnDate = [[NSPredicate alloc] init];
if (isAllDay)
predicateForEventOnDate = [store predicateForEventsWithStartDate:start endDate:finish calendars:nil];
NSArray *eventOnDate = [store eventsMatchingPredicate:predicateForEventOnDate];
这将产生一个数组,覆盖从头到尾全天的事件。
关于ios - 检查日历上是否存在事件,我们在Stack Overflow上找到一个类似的问题:https://stackoverflow.com/questions/35140105/