Ios 当每个部分的行数不同时，如何获取numberOfRows的计数？

我试图用XML文件中的条目填充tableview。到目前为止，我已经将XML文件解析为一个结构，并编写了titleForHeaderInSection和numberOfSections的方法，但我正在努力通过计算每个

中的

条目来计算每个节的numberOfRows。我认为我的主要困难来自不理解如何使用[部分]。以下是我迄今为止所做的工作：

我解析了一个xml文件，该文件包含如下日历日期和事件。您将看到第一个calendarevent如何有2个假日和描述条目，而第二个有1个：

<calendar>
    <calendarevent>
        <month>October</month>
        <dateevent>2018 10 01</dateevent>
        <datenumber>01</datenumber>

        <holiday>First Holiday</holiday>
        <description>aaaaaaaaaa</description>

        <holiday>Second Holiday</holiday>
        <description>bbbbbbbbbb</description>

    </calendarevent>
    <calendarevent>
        <month>October</month>
        <dateevent>2018 10 10</dateevent>
        <datenumber>10</datenumber>

        <holiday>Third Holiday</holiday>
        <description>ccccccccccc</description>

    </calendarevent>
    .... and so on

以下是我的XML解析器代码：

class CalendarViewController {
    var myCalendarDatesFromStrut = [CalendarDates]()
    var myCalendarEventsFromStrut = [CalendarDates.CalendarEvents]()
}

extension CalendarViewController {
    func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String] = [:]) {
        calendarEventsElementFromXML = elementName
    }

    func parser(_ parser: XMLParser, foundCharacters string: String) {
        let data = string.trimmingCharacters(in: CharacterSet.whitespacesAndNewlines)
        if data.count != 0 {
            switch calendarEventsElementFromXML
            {
            case "month": monthsFromXML = data
            case "dateevent": eventdatesFromXML = data
            case "datenumber": eventdatenumbersFromXML = data
            case "holiday": holidaysFromXML = data
            default: break
            }
        }
    }

    func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
        if elementName == "calendarevent" {
            var myCalendarDates = CalendarDates.CalendarEvents()
            myCalendarDates.month = monthsFromXML
            myCalendarDates.eventdate = eventdatesFromXML
            myCalendarDates.eventdatenumber = eventdatenumbersFromXML
            myCalendarDates.holiday = holidaysFromXML
            myCalendarEventsFromStrut.append(myCalendarDates)
        }
    }
}

因此，在解析XML并将其附加到结构之后，我开始获取tableview的值

如果

与当前日期月相同，则每个部分由一个

组成。XML有其他月份的

，所以我不想要所有的。我检查XML中的当前月份是否为==月份，如果是，则计算numberOfSections的dateevents数，并将dateevents格式化为这些节的标题

然后，节中的每一行在相应的

中表示一个

---

首先，XML可能在一个

calendarevent

中包含多个

holiday

元素，因此您需要更新

CalendarEvents

以能够容纳多个假日

struct Holiday {
    var title: String = ""
    var description: String = ""
}

//You should better avoid plural form for something which represents a single object
struct CalendarEvent {
    var month: String = ""
    var eventdate: String = ""
    var eventdatenumber: String = ""
    //Better use plural form for the name representing multiple objects
    var holidays: [Holiday] = []
}

（我删除了外部结构CalendarDates，因为我找不到任何需要嵌套类型的原因。此外，我建议您避免使用复数形式来命名表示单个对象的对象。）

---

要使用结构解析XML，需要在

XMLParserDelegate

中使用更多属性：

class CalendarViewController: UIViewController {
    //`myCalendarEventsFromStrut` is too long and `FromStrut` does not make sense
    var myCalendarEvents: [CalendarEvent] = []

    //Properties needed for parsing your XML
    var textCurrentlyParsed: String? = nil
    var monthFromXML: String = ""
    var dateeventFromXML: String = ""
    var datenumberFromXML: String = ""
    var holidaysFromXML: [Holiday] = []

    //Your table view shows some selected evnets in `myCalendarEvents`,
    //To improve response, you should beter keep the filtered result, when `selectedDate` is updated.
    var selectedDate: Date? {
        didSet {
            if let date = selectedDate {
                let currentMonthShown = monthFormatter.string(from: date)
                allEventsInVisibleMonth = myCalendarEvents.filter({ $0.month == currentMonthShown })
            } else {
                allEventsInVisibleMonth = [] //Or you prefer `allEventsInVisibleMonth = myCalendarEvents`?
            }
        }
    }
    var allEventsInVisibleMonth: [CalendarEvent] = []

    //You may have this sort of constants somewhere, this is just an example
    let TheCellID = "cell" //Change this according to your actual setups

    //
    // Date formatters.
    //  Better keep distinct DateFormaters accoding to the format to avoid simple mistakes
    //

    let monthFormatter: DateFormatter = {
       let formatter = DateFormatter()
        formatter.locale = Locale(identifier: "en_US_POSIX")
        formatter.dateFormat = "MMMM"
        return formatter
    }()

    let dateeventFormatter: DateFormatter = {
        let formatter = DateFormatter()
        formatter.locale = Locale(identifier: "en_US_POSIX")
        formatter.dateFormat = "yyyy MM dd"
        return formatter
    }()

    let sectionHeaderFormatter: DateFormatter = {
        let formatter = DateFormatter()
        formatter.locale = Locale(identifier: "en_US_POSIX")
        formatter.dateFormat = "yyyy-MM-dd"
        return formatter
    }()

    //...
}

（上面的代码添加了一些内容来编写

UITableViewDataSource

方法的示例。）

使用上述属性，您可以编写

XMLParserDelegate

方法，如下所示：

extension CalendarViewController: XMLParserDelegate {
    func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String] = [:]) {
        switch elementName {
        case "month", "dateevent", "datenumber", "holiday", "description":
            //Reset the text content for the element
            textCurrentlyParsed = ""
        case "calendarevent":
            //Reset all variables which may contain the result of previous element
            monthFromXML = ""
            dateeventFromXML = ""
            datenumberFromXML = ""
            holidaysFromXML = []
        case "calendar":
            //Can be ignored
            break
        default:
            print("Unexpected start tag:", elementName)
            break
        }
    }

    func parser(_ parser: XMLParser, foundCharacters string: String) {
        //`parser(_:foundCharacters:)` may be called several times for a seemingly single text content,
        //So you need to add the `string` to the currently parsed text
        textCurrentlyParsed? += string
    }

    func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
        switch elementName {
        case "calendarevent":
            var calendarEvent = CalendarEvent()
            calendarEvent.month = monthFromXML
            calendarEvent.eventdate = dateeventFromXML
            calendarEvent.eventdatenumber = datenumberFromXML
            calendarEvent.holidays = holidaysFromXML
            myCalendarEvents.append(calendarEvent)
        case "month":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                monthFromXML = parsedText
            }
        case "dateevent":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                dateeventFromXML = parsedText
            }
        case "datenumber":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                datenumberFromXML = parsedText
            }
        case "holiday":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                var holiday = Holiday()
                holiday.title = parsedText
                holidaysFromXML.append(holiday)
            }
            break
        case "description":
            if
                let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines),
                case let lastIndexOfHoliday = holidaysFromXML.count - 1, lastIndexOfHoliday >= 0
            {
                //You need to modify the last entry in `holidaysFromXML`
                holidaysFromXML[lastIndexOfHoliday].description = parsedText
            }
        default:
            print("Unexpected end tag:", elementName)
            break
        }
    }
}

（如果您不需要对文本进行

修剪

，则可以稍微简化上面的代码。）

---

包含这些代码后，您的

UITableViewDataSource

方法将如下所示：

struct CalendarDates {
    struct CalendarEvents {
        var month = ""
        var eventdate = ""
        var eventdatenumber = ""
        var holiday = ""
        var description = ""
        }
}

extension CalendarViewController: UITableViewDelegate, UITableViewDataSource {
    func numberOfSections(in tableView: UITableView) -> Int {
        return allEventsInVisibleMonth.count
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return allEventsInVisibleMonth[section].holidays.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let eventForTheSection = allEventsInVisibleMonth[indexPath.section]
        let holidayForTheRow = eventForTheSection.holidays[indexPath.row]
        let cell = tableView.dequeueReusableCell(withIdentifier: TheCellID, for: indexPath)
        //... setup the cell using `eventForTheSection` and `holidayForTheRow`
        return cell
    }

    // Prints <dateevent> reformatted as section header
    func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
        let eventForTheSection = allEventsInVisibleMonth[section]
        if let eventdateAsDate = dateeventFormatter.date(from: eventForTheSection.eventdate) {
            return sectionHeaderFormatter.string(from: eventdateAsDate)
        } else {
            return "Broken eventdate: \(eventForTheSection.eventdate)"
        }
    }

}

扩展日历视图控制器：UITableViewDelegate，UITableViewDataSource{ func numberOfSections（在tableView:UITableView中）->Int{ 返回allEventsInVisibleMonth.count } func tableView（tableView:UITableView，numberofrowsinssection:Int）->Int{ 返回allEventsInVisibleMonth[节].holidays.count } func tableView（tableView:UITableView，cellForRowAt indexath:indexPath）->UITableViewCell{ 让eventForTheSection=allEventsInVisibleMonth[indexPath.section] 让holidayForTheRow=eventForTheSection.holidays[indexPath.row] let cell=tableView.dequeueReusableCell（标识符：TheCellID，for:indexath） //…使用'eventForTheSection'和'holidayForTheRow'设置单元格` 返回单元 } //打印重新格式化为节标题的内容 func tableView（tableView:UITableView，titleForHeaderInSection:Int）->String{ 让eventForTheSection=AllEventsVisiblemon[节] 如果让eventdateAsDate=dateeventFormatter.date（发件人：eventForTheSection.eventdate）{ 返回节HeadPerformatter.string（from:eventdateAsDate） }否则{ 返回“断开的eventdate:\（节的eventForTheSection.eventdate）” } } } （未测试，您可能需要一些修复。）

通常，

UITableViewDataSource

方法可以经常调用，因此您应该高效地实现它们

因此，不建议在每次调用时创建筛选数组。 您最好仅在以下情况下更新

allEventsInVisibleMonth

：

• myCalendarEvents

  已更新（不包括在上述我的代码中）

• selectedDate

  已更新（

  selectedDate

  中的

  didSet

  将执行此操作）

---

---

有点长，但我认为值得一试。

您的

部分似乎没有明确定义。你想在每个部分展示什么？在当前的
numberOfSections（In:）
中，返回特定月份的日历事件数。这意味着每个部分包含一个日历事件，这真的是你想要的吗？请澄清您希望在每个部分中显示的内容。在numberOfSections中，我检查是否与当前日期月相同，然后查找并显示与当前月份相同的部分。然后，我为各部分创建标题。对于numberOfRows，我想获得每个行的#of，并显示该行的#。所以在示例XML中，我有两个条目，所以我想要两行@OOPerOk，有些事情已经弄清楚了：每个部分由一个组成/一个部分中的每一行代表对应的一个，对吗？@OOPer是的，就是这样。我使用的是计算numOfsection，因为我只需要获取当前月份的月份，而不是所有包含其他月份的条目的月份。是的，节中的每一行代表对应的每一行中的一行，那么您可能需要更改
CalendarEvents
的定义，因为它只能容纳一个假日，还需要对
XMLParserDelegate
方法进行大量更新。你最好在你的问题中包括我上面写的两件事。有人会比我回答得更快，给出了一些明确的定义。这非常有帮助，尤其是解释。非常感谢你！我个人理解的一个问题是：在XML解析中，我看到一行代码是“case let lastIndexOfHoliday=holidaysFromXML.count-1，lastIndexOfHoliday>=0”。我真的不明白那是什么意思？我知道你是如何先解析日历事件，然后解析假日的。在CalendarEvents中，您似乎不检查是否有最后一个条目，但在假日中您会检查吗？第二个问题：我想
extension CalendarViewController: XMLParserDelegate {
    func parser(_ parser: XMLParser, didStartElement elementName: String, namespaceURI: String?, qualifiedName qName: String?, attributes attributeDict: [String : String] = [:]) {
        switch elementName {
        case "month", "dateevent", "datenumber", "holiday", "description":
            //Reset the text content for the element
            textCurrentlyParsed = ""
        case "calendarevent":
            //Reset all variables which may contain the result of previous element
            monthFromXML = ""
            dateeventFromXML = ""
            datenumberFromXML = ""
            holidaysFromXML = []
        case "calendar":
            //Can be ignored
            break
        default:
            print("Unexpected start tag:", elementName)
            break
        }
    }

    func parser(_ parser: XMLParser, foundCharacters string: String) {
        //`parser(_:foundCharacters:)` may be called several times for a seemingly single text content,
        //So you need to add the `string` to the currently parsed text
        textCurrentlyParsed? += string
    }

    func parser(_ parser: XMLParser, didEndElement elementName: String, namespaceURI: String?, qualifiedName qName: String?) {
        switch elementName {
        case "calendarevent":
            var calendarEvent = CalendarEvent()
            calendarEvent.month = monthFromXML
            calendarEvent.eventdate = dateeventFromXML
            calendarEvent.eventdatenumber = datenumberFromXML
            calendarEvent.holidays = holidaysFromXML
            myCalendarEvents.append(calendarEvent)
        case "month":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                monthFromXML = parsedText
            }
        case "dateevent":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                dateeventFromXML = parsedText
            }
        case "datenumber":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                datenumberFromXML = parsedText
            }
        case "holiday":
            if let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines) {
                var holiday = Holiday()
                holiday.title = parsedText
                holidaysFromXML.append(holiday)
            }
            break
        case "description":
            if
                let parsedText = textCurrentlyParsed?.trimmingCharacters(in: .whitespacesAndNewlines),
                case let lastIndexOfHoliday = holidaysFromXML.count - 1, lastIndexOfHoliday >= 0
            {
                //You need to modify the last entry in `holidaysFromXML`
                holidaysFromXML[lastIndexOfHoliday].description = parsedText
            }
        default:
            print("Unexpected end tag:", elementName)
            break
        }
    }
}

extension CalendarViewController: UITableViewDelegate, UITableViewDataSource {
    func numberOfSections(in tableView: UITableView) -> Int {
        return allEventsInVisibleMonth.count
    }

    func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
        return allEventsInVisibleMonth[section].holidays.count
    }

    func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
        let eventForTheSection = allEventsInVisibleMonth[indexPath.section]
        let holidayForTheRow = eventForTheSection.holidays[indexPath.row]
        let cell = tableView.dequeueReusableCell(withIdentifier: TheCellID, for: indexPath)
        //... setup the cell using `eventForTheSection` and `holidayForTheRow`
        return cell
    }

    // Prints <dateevent> reformatted as section header
    func tableView(_ tableView: UITableView, titleForHeaderInSection section: Int) -> String? {
        let eventForTheSection = allEventsInVisibleMonth[section]
        if let eventdateAsDate = dateeventFormatter.date(from: eventForTheSection.eventdate) {
            return sectionHeaderFormatter.string(from: eventdateAsDate)
        } else {
            return "Broken eventdate: \(eventForTheSection.eventdate)"
        }
    }

}