Question

嘿，我无法访问我的全局数组，因为它是空的。我知道我已经在此链接How to access global array in Swift 4?

中提出了这个问题

但是他们没有在代码中显示它，所以我不知道如何实现它。谁能告诉我该怎么做？这是我的代码

var prayers = [Prayer]() //This is my global array

func fetchPrayer() {
    guard let city = self.city else { return}

    self.prayers = []
    APIServices.shared.fetchPrayer(name: city) { (results) in
        results.datetime.forEach({ (time) in
            let shubuh = Prayer(prayerName: "Shubuh", prayerIcon: #imageLiteral(resourceName: "PartlyCloudyNight"), prayerTime: time.times.Fajr)
            let dzuhur = Prayer(prayerName: "Dzuhur", prayerIcon: #imageLiteral(resourceName: "Sunny"), prayerTime: time.times.Dhuhr)
            let ashar = Prayer(prayerName: "Ashar", prayerIcon: #imageLiteral(resourceName: "PartlyCloudyDay"), prayerTime: time.times.Asr)
            let maghrib = Prayer(prayerName: "Maghrib", prayerIcon: #imageLiteral(resourceName: "Overcast"), prayerTime: time.times.Maghrib)
            let isya = Prayer(prayerName: "Isya", prayerIcon: #imageLiteral(resourceName: "Clear"), prayerTime: time.times.Isha)
            self.prayers.append(contentsOf: [shubuh, dzuhur, ashar, maghrib, isya])

        })
        DispatchQueue.main.async {
            self.updateUI()
            self.tableView.reloadData()
        }
    }
}

这是我的表格视图代码，我将func setupTableView放入viewDidLoad

extension PrayerController: UITableViewDelegate, UITableViewDataSource {
func setupTableView() {
    tableView.delegate = self
    tableView.dataSource = self
    tableView.register(PrayerTimeViewCell.self, forCellReuseIdentifier: self.cellId)
    tableView.separatorColor = .clear
    tableView.backgroundColor = .clear
    tableView.rowHeight = 53
}

//MARK:- TableView
func tableView(_ tableView: UITableView, numberOfRowsInSection section: Int) -> Int {
    return prayers.count
}

func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {
    let cell = tableView.dequeueReusableCell(withIdentifier: cellId, for: indexPath) as! PrayerTimeViewCell

    let prayer = prayers[indexPath.row]
    cell.prayer = prayer

    return cell
  }
}

这是代码的错误索引超出范围的地方

func updateUI() {
    let prayer0 = prayers[0].prayerTime
    let prayer1 = prayers[1].prayerTime
    let prayer2 = prayers[2].prayerTime
    let prayer3 = prayers[3].prayerTime
    let prayer4 = prayers[4].prayerTime
}

Answer 1

首先，您如何确定在致电prayers时updateUI阵列中有五个祈祷？

第二，应避免可能并发访问全局变量。我建议按以下方式修改您的代码：

APIServices.shared.fetchPrayer(name: city) { (results) in
    var newPrayers = [Prayer]()
    results.datetime.forEach({ (time) in
        let shubuh = Prayer(prayerName: "Shubuh", prayerIcon: #imageLiteral(resourceName: "PartlyCloudyNight"), prayerTime: time.times.Fajr)
        let dzuhur = Prayer(prayerName: "Dzuhur", prayerIcon: #imageLiteral(resourceName: "Sunny"), prayerTime: time.times.Dhuhr)
        let ashar = Prayer(prayerName: "Ashar", prayerIcon: #imageLiteral(resourceName: "PartlyCloudyDay"), prayerTime: time.times.Asr)
        let maghrib = Prayer(prayerName: "Maghrib", prayerIcon: #imageLiteral(resourceName: "Overcast"), prayerTime: time.times.Maghrib)
        let isya = Prayer(prayerName: "Isya", prayerIcon: #imageLiteral(resourceName: "Clear"), prayerTime: time.times.Isha)
        newPrayers.append(contentsOf: [shubuh, dzuhur, ashar, maghrib, isya])

    })
    DispatchQueue.main.async {
        self.prayers = newPrayers
        self.updateUI()
        self.tableView.reloadData()
    }
}

在这里，您可以在newPrayers闭包中创建本地fetchPrayer数组。填充数组，完成后，在主线程中，然后通过将self.prayers分配给新数组来“发布”结果。

尽管如此，在updateUI中，您应明确检查数组中元素的数量是否正确。

异步后如何使全局数组不为空

1 个答案: