如何在 Swift 中使用坐标触发 EventKit 警报

Question

我不知道其他人，但 EventKit 似乎很少有在线资源和教程供您参考以寻求帮助。

当用户点击一组坐标的半径时，我需要触发警报，我不确定最好的方法，我在本地通知和 EventKit 提醒之间徘徊。

我决定使用 eventKit，因为我觉得我可以用更多的警报做更多的事情，这是最实用的方法，但是我对 EventKit 了解不多，我遇到了一些问题。

无论如何，我已经设法聚在一起并构建了一个示例项目，该项目可以在用户离开当前位置时触发警报，唯一的问题是，我几乎想要做完全相反的事情，我想要为了在用户输入一组坐标时触发警报，我假设大部分代码都是可转移的，但我似乎主要停留在一个位上。

// Creates an EKStructuredLocation Instance with a title of "Current Location"
    let location = EKStructuredLocation(title: "Current Location")
    // Uses the last location update extracted from the locations array to supply you're current location
    location.geoLocation = locations.last as! CLLocation


    // Location is added to a newly created alarm instance
    let alarm = EKAlarm()
    alarm.structuredLocation = location
    // This alarm is triggered when the user moves away from the location proximity
    alarm.proximity = EKAlarmProximityLeave
    stationReminder.addAlarm(alarm)

我正在努力寻找如何将警报的位置设置为坐标而不是用户位置。

我尝试改变这个

location.geoLocation = locations.last as! CLLocation

到

location.geoLocation = CLCircularRegion(circularRegionWithCenter: CLLocationCoordinate2D(latitude: 37.33233141, longitude: -122.03121860), radius: 50.0, identifier: "Location1")

但这不起作用，我相信我在正确的轨道上，但我抛出了这个错误：Cannot assign a value of type 'CLCircularRegion!' to a value of type 'CLLocation!'

我尝试了很多事情都没有解决，有没有人有这方面的经验并且知道如何提供帮助？

我还假设我必须从这里更改以下内容

alarm.proximity = EKAlarmProximityLeave

到这里

alarm.proximity = EKAlarmProximityEnter

更新

我已经在下面加入了一些 cmets 并尝试了很多其他的东西来让它工作，我觉得我很接近，但只是缺少一些东西。我无法触发此警报。请原谅所有代码 cmets，这只是为了让您可以看到我为解决此问题所做的一些尝试。

谁能看出这个警报代码有什么问题？

func locationManager(manager: CLLocationManager!, didUpdateLocations locations: [AnyObject]!) {

    // Stops location manager from sending further updates
    locationManager.stopUpdatingLocation()

    // Creates a new EKReminder which is named and initialised with text from the UITextField
    let stationReminder = EKReminder(eventStore: appDelegate!.eventStore)
    stationReminder.title = locationText.text

    // Stores the previously created EKReminder in the default calendar
    stationReminder.calendar = appDelegate!.eventStore!.defaultCalendarForNewReminders()

    // Creates an EKStructuredLocation Instance with a title of "Current Location"
    let location = EKStructuredLocation(title: "Destination: Bournemouth Station")
    // Uses the last location update extracted from the locations array to supply you're current location
//        location.geoLocation = locations.last as! CLLocation
//        location.geoLocation = CLCircularRegion(circularRegionWithCenter: CLLocationCoordinate2D(latitude: 37.33233141, longitude: -122.03121860), radius: 50.0, identifier: "Location1")
//        location.geoLocation = CLLocation(latitude: 50.742771, longitude: -1.895072)
    location.radius = 50.0

    location.geoLocation = CLLocation(latitude:50.742771, longitude:-1.895072)
//        location.radius = 10.0 // metres

    // Location is added to a newly created alarm instance
    let alarm = EKAlarm()
    alarm.structuredLocation = location
    // This alarm is triggered when the user moves away from the location proximity
//        alarm.proximity = EKAlarmProximityEnter
    alarm.proximity = EKAlarmProximityEnter // "geofence": we alarm when *arriving*
    // but this will have no effect until Reminders is granted Location access...
    // and in iOS 8 it won't even ask for it until it is launched
    // also, in iOS 8 the separate background usage pref is withdrawn;
    // instead, auth of Reminders for "when in use" covers this...
    // ...because it means "this app *or one of its features* is visible on screen"
    stationReminder.addAlarm(alarm)

    // Now we have a fully configured reminder which we save in the Event Store
    var error: NSError?
    appDelegate!.eventStore?.saveReminder(stationReminder,
        commit: true, error: &error)

    if error != nil {
        println("Reminder failed with error \(error?.localizedDescription)")
    }
}

Answer 1

看起来 EKEvent 有一个 EKStructuredLocation，您使用正确。但是，您需要注意 geoLocation 属性的类型。它应该是一个 CLLocation，它与一个 CLCircularRegion 不同。

修复步骤：

1. 查看 EKStructuredLocation https://developer.apple.com/library/mac/documentation/EventKit/Reference/EKStructuredLocationClassRef/index.html 的文档

2. 将 location.geoLocation 设置为您根据纬度、经度坐标创建的 CLLocation。 （查看CLLocation 的文档：https://developer.apple.com/library/mac/documentation/CoreLocation/Reference/CLLocation_Class/index.html#//apple_ref/swift/cl/CLLocation） geoLocation = CLLocation(latitude: 37.33233141, longitude: -122.03121860)

3. 单独设置geoLocation.radius location.radius = 50.0
4. 此时设置 proximityEnter 应该可以按预期工作