Question

尝试将计时器设置为在tableViewCell内的标签上显示时间。

由于我缺乏知识，我面临着这个问题。

我熟悉Timer，但我可以找到最有效的方法。

非常感谢

这是我的代码

override func tableView(_ tableView: UITableView, cellForRowAt indexPath: IndexPath) -> UITableViewCell {


            let cell = tableView.dequeueReusableCell(withIdentifier: "WeatherCellLocation", for: indexPath) as! WeatherCellLocationCell

            let place = fetchedResultsController.object(at: indexPath)
         // var timer = Timer.scheduledTimer(timeInterval: 60, target: self, selector: #selector(updateTime), userInfo: indexPath, repeats: true)
            cell.configureCell(weatherPlace: place)

            return cell

    }

这里我正在加载tableView

Answer 1

首先在单元格中添加WeatherPlaceData对象并将计时器放入单元格

var currentWeatherPlaceData: WeatherPlaceData?
fileprivate var timeWorking : Bool = false
var timer:Timer?

添加更新标签的方法

func updateTime()
    {
       localTime.text = DateFormatter.localizedString(from: self.currentWeatherPlaceData.localDate, dateStyle: .none, timeStyle: .short)
    }

将您的configureCell方法更改为此方法

func configureCell(weatherPlace : WeatherPlaceData){
        self.currentWeatherPlaceData = weatherPlace
        if(!timeWorking)
        {
        localTime.text = DateFormatter.localizedString(from: self.currentWeatherPlaceData.localDate, dateStyle: .none, timeStyle: .short)
        timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(self.updateTime), userInfo: nil, repeats: true)
        self.timeWorking = true
        }

        cityName.text = weatherPlace.name
        let temp = Int(weatherPlace.currentTemp)
        currentTemp.text = "\(temp)"

    }

最后调整准备重用以避免问题，重新启动计时器

override func prepareForReuse() {
    super.prepareForReuse()
    self.timer.invalidate()
    self.timeWorking = false
}

希望这有帮助

Answer 2

我会向单元格本身添加一个Timer，每秒重新计算一次。

class WeatherCellLocationCell: UITableViewCell {

@IBOutlet weak var localTime: UILabel!
@IBOutlet weak var cityName: UILabel!
@IBOutlet weak var currentTemp: UILabel!

var timer: Timer?
var weatherPlace: WeatherPlaceData?

func configureCell(weatherPlace : WeatherPlaceData){
    self.weatherPlace = weatherPlace
    setTime()
    timer = Timer.scheduledTimer(timeInterval: 1.0, target: self, selector: #selector(WeatherCellLocationCell.setTime), userInfo: nil, repeats: true)
}

func setTime() {
    localTime.text = DateFormatter.localizedString(from: weatherPlace.localDate, dateStyle: .none, timeStyle: .short)

    cityName.text = weatherPlace.name
    let temp = Int(weatherPlace.currentTemp)
    currentTemp.text = "\(temp)"
}

override func awakeFromNib() {
    super.awakeFromNib()
}

override func setSelected(_ selected: Bool, animated: Bool) {
    super.setSelected(selected, animated: animated)
}

override func prepareForReuse() {
    if timer != nil {
        timer?.invalidate()
        timer = nil
    }
}

}

使用Timer在UILabel中设置时间在UITableViewCell中

2 个答案: