【问题标题】：Swift: Date sorting EKEvents after fetching from EKEventStore into tableView dataSwift：从 EKEventStore 获取到 tableView 数据后对 EKEvents 进行日期排序
【发布时间】：2018-08-22 16:12:45
【问题描述】：

简介

上下文：

我正在开发一个小应用程序，我在其中使用 EKEventStore 来获取用户事件。我正在获取接下来 10 天（从用户打开应用程序时开始）的所有 EKEvents，并将它们存储到 EKEvents 数组中。然后我想对它们进行排序（见下文）并将它们用作我的 tableView 日历的数据。

问题：

我想要数组的以下结构：var allDayEvents : [[EKEvent]]? 和 var dateIntervalEvents : [[EKEvent]]?。其中有一个静态 11 索引 (0-10)。
我相信我正在填充的代码比它必须的要多得多。对于我和性能而言，必须有一种更快的方法。

问题：

如何有效地将 EventStore 查询中获取的事件排序为 allDayEvents 和 dateIntervalEvents 的语法？
1. 我需要对日期进行排序，以便最早在数组的每个部分中排在第一位。

tableView结构说明：

我有 11 个部分对应于接下来的 11 天。（所以是11段的静态值）
我想显示该部分提供的日期的事件。
此外，并非全天事件的事件将首先显示在一个单元格类型的部分中，然后将全天事件显示在另一个单元格类型中。
为我的数据中的以下语法留出空间：dateIntervalEvents[indexPath.section][indexPath.row] 和 allDayEvents[indexPath.section][indexPath.row]

代码：

我的 fetch 方法。

    var allDayEvents : [EKEvent]?
    var dateIntervalEvents : [EKEvent]?

    private func getEventsFromCalendarStore() {

        let eventStore = EKEventStore()
        var fetchedEvents : [EKEvent]?
        //simulator? either way wrong dates are fetched
        guard let startDate = Calendar.current.date(byAdding: .day, value: -1, to: Date()) else { return }
        guard let endDate = Calendar.current.date(byAdding: .day, value: 10, to: startDate) else { return }

        let eventPredicate = eventStore.predicateForEvents(withStart: startDate, end: endDate, calendars: userCalendars)
        fetchedEvents = eventStore.events(matching: eventPredicate)

        //Basically how to sort fetchedEvents to get the required structure of my array.

    }

我对数组排序的尝试：

private func getEventsFromCalendarStore() {

     let eventStore = EKEventStore()
     var fetchedEvents : [EKEvent] = []
     var allDayers : [EKEvent] = []
     var dateIntervalls : [EKEvent] = []

    var allDay1 : [EKEvent] = []
     var allDay2 : [EKEvent] = []
     var allDay3 : [EKEvent] = []
     var allDay4 : [EKEvent] = []
     var allDay5 : [EKEvent] = []
     var allDay6 : [EKEvent] = []
     var allDay7 : [EKEvent] = []
     var allDay8 : [EKEvent] = []
     var allDay9 : [EKEvent] = []
     var allDay10 : [EKEvent] = []
     var allDay11 : [EKEvent] = []

     var dIDay1 : [EKEvent] = []
     var dIDay2 : [EKEvent] = []
     var dIDay3 : [EKEvent] = []
     var dIDay4 : [EKEvent] = []
     var dIDay5 : [EKEvent] = []
     var dIDay6 : [EKEvent] = []
     var dIDay7 : [EKEvent] = []
     var dIDay8 : [EKEvent] = []
     var dIDay9 : [EKEvent] = []
     var dIDay10 : [EKEvent] = []
     var dIDay11 : [EKEvent] = []

     guard let startDate = Calendar.current.date(byAdding: .day, value: -1, to: Date()) else { return }
     guard let endDate = Calendar.current.date(byAdding: .day, value: 10, to: startDate) else { return }

     let eventPredicate = eventStore.predicateForEvents(withStart: startDate, end: endDate, calendars: userCalendars)

     //getting all events and sorting them in date order.
     fetchedEvents = eventStore.events(matching: eventPredicate).sorted(by: { (e1 : EKEvent, e2 : EKEvent) -> Bool in
         return e1.compareStartDate(with: e2) == .orderedAscending
     })

     //This cant be best practice of sorting it the following way?
     print(fetchedEvents)

     for event in fetchedEvents {

         if event.isAllDay == true {
             allDayers.append(event)
         } else {
           dateIntervalls.append(event)
         }
     }

     for event in dateIntervalls {

         if event.startDate == startDate {
             dIDay1.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay2.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay3.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay4.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay5.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay6.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay7.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay8.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay9.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay10.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             dIDay11.append(event)
         }

     }

     for event in allDayers {
         if event.startDate == startDate {
             allDay1.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay2.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay3.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay4.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay5.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay6.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay7.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay8.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay9.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay10.append(event)
         } else if event.startDate == Calendar.current.date(byAdding: .day, value: 1, to: startDate) {
             allDay11.append(event)
         }
     }

     allDayEvents?.insert(allDay1, at: 0)
     allDayEvents?.insert(allDay2, at: 1)
     allDayEvents?.insert(allDay3, at: 2)
     allDayEvents?.insert(allDay4, at: 3)
     allDayEvents?.insert(allDay5, at: 4)
     allDayEvents?.insert(allDay6, at: 5)
     allDayEvents?.insert(allDay7, at: 6)
     allDayEvents?.insert(allDay8, at: 7)
     allDayEvents?.insert(allDay9, at: 8)
     allDayEvents?.insert(allDay10, at: 9)
     allDayEvents?.insert(allDay11, at: 10)

     dateIntervalEvents?.insert(dIDay1, at: 0)
     dateIntervalEvents?.insert(dIDay2, at: 1)
     dateIntervalEvents?.insert(dIDay3, at: 2)
     dateIntervalEvents?.insert(dIDay4, at: 3)
     dateIntervalEvents?.insert(dIDay5, at: 4)
     dateIntervalEvents?.insert(dIDay6, at: 5)
     dateIntervalEvents?.insert(dIDay7, at: 6)
     dateIntervalEvents?.insert(dIDay8, at: 7)
     dateIntervalEvents?.insert(dIDay9, at: 8)
     dateIntervalEvents?.insert(dIDay10, at: 9)
     dateIntervalEvents?.insert(dIDay11, at: 10)

}

你会如何处理这种数组结构的排序？

感谢您阅读我的帖子。

【问题讨论】：

标签： ios swift sorting calendar eventkit

【解决方案1】：

首先，去掉你的两组 11 个数组。将每个替换为嵌套数组。

接下来，在填充 allDayers 和 dateIntervals 之后，您应该对它们进行排序。

然后就可以对两个数组中的每个事件进行迭代，计算与开始日期相差的天数，更新对应的嵌套数组。

private func getEventsFromCalendarStore() {
    guard let startDate = Calendar.current.date(byAdding: .day, value: -1, to: Date()) else { return }
    guard let endDate = Calendar.current.date(byAdding: .day, value: 10, to: startDate) else { return }

    let eventStore = EKEventStore()
    var fetchedEvents : [EKEvent] = []
    var allDayers : [EKEvent] = []
    var dateIntervals : [EKEvent] = []

    let eventPredicate = eventStore.predicateForEvents(withStart: startDate, end: endDate, calendars: userCalendars)

    //getting all events and sorting them in date order.
    fetchedEvents = eventStore.events(matching: eventPredicate).sorted(by: { (e1 : EKEvent, e2 : EKEvent) -> Bool in
        return e1.compareStartDate(with: e2) == .orderedAscending
    })

    //This cant be best practice of sorting it the following way?
    print(fetchedEvents)

    for event in fetchedEvents {
        if event.isAllDay == true {
            allDayers.append(event)
        } else {
            dateIntervals.append(event)
        }
    }

    allDayers.sort { $0.startDate < $1.startDate  }
    dateIntervals.sort { $0.startDate < $1.startDate  }

    var groupedAllDayers = Array(repeating: [EKEvent](), count: 11)
    var groupedIntervals = Array(repeating: [EKEvent](), count: 11)

    for event in dateIntervals {
        let days = Calendar.current.dateComponents([.day], from: startDate, to: event.startDate).day!
        groupedIntervals[days].append(event)
    }
    for event in allDayers {
        let days = Calendar.current.dateComponents([.day], from: startDate, to: event.startDate).day!
        groupedAllDayers[days].append(event)
    }
}

最后，groupedAllDayers 和 groupedIntervals 将包含您的两组事件，每组按从startDate 到事件的startDate 的天数分组。

【讨论】：

由于fetchedEvents （显然）已经排序，是否真的需要（重新）排序单独的数组？
@DavidBerry 不错。我没有注意到最初的排序。你是对的，不需要对两个数组进行额外的排序，因为fetchedEvent 已经按开始日期排序。
我想我也会完全消除 allDayers 和 dateIntervals 并通过 fetchedEvents 转储到适当的桶中，但这只是挑剔。
优美的语法。它的作用就像红酒和法国奶酪。