Weather Cast App

What I learned

A quick look at SWIFT code

var body: some View {
 Chart{
 ForEach(weeklyData) { series in
 ForEach(series.temperatureData, id: \.day) { data in
 LineMark(
 x: .value("Day", data.day, unit: .day),
 y: .value("Temperature", data.temperature)
 )
 .foregroundStyle(by: .value("TemperatureType", series.temperatureType))
 .symbol(by: .value("TemperatureType", series.temperatureType))
 .interpolationMethod(.catmullRom)
 }
 }
 if let selectedDate {
 RuleMark(
 x: .value("Selected", selectedDate, unit: .day)
 )
 .foregroundStyle(Color.gray.opacity(0.3))
 .zIndex(1)
 .annotation(
 position: .top, spacing: 0,
 overflowResolution: .init(
 x: .fit(to: .chart),
 y: .disabled
 )
 ) {
 valueSelectionPopover
 }
 }
 }
 .chartForegroundStyleScale { colorTemperature[0ドル]! }
 .chartSymbolScale([
 "Max Temperature": Circle().strokeBorder(lineWidth: 2),
 "Min Temperature": Square().strokeBorder(lineWidth: 2)
 ])
 .chartXAxis {
 AxisMarks(values: .stride(by: .day)) { _ in
 AxisTick()
 AxisGridLine()
 AxisValueLabel(format: .dateTime.weekday(.abbreviated), centered: true)
 }
 }
 .chartXSelection(value: $rawSelectedDate)
}
// Mock data
static let weeklydata: [WeatherSeries] = [
 .init(temperatureType: "Max Temperature", temperatureData: [
 (day: date(year: 2022, month: 5, day: 2), temperature: Float(15.3)),
 (day: date(year: 2022, month: 5, day: 3), temperature: Float(6.2)),
 (day: date(year: 2022, month: 5, day: 4), temperature: Float(19.1)),
 (day: date(year: 2022, month: 5, day: 5), temperature: Float(15.4)),
 (day: date(year: 2022, month: 5, day: 6), temperature: Float(4.5)),
 (day: date(year: 2022, month: 5, day: 7), temperature: Float(11)),
 (day: date(year: 2022, month: 5, day: 8), temperature: Float(19.9))
 ]),
 .init(temperatureType: "Min Temperature", temperatureData: [
 (day: date(year: 2022, month: 5, day: 2), temperature: Float(5.3)),
 (day: date(year: 2022, month: 5, day: 3), temperature: Float(-6.2)),
 (day: date(year: 2022, month: 5, day: 4), temperature: Float(9.1)),
 (day: date(year: 2022, month: 5, day: 5), temperature: Float(-15.4)),
 (day: date(year: 2022, month: 5, day: 6), temperature: Float(-4.5)),
 (day: date(year: 2022, month: 5, day: 7), temperature: Float(-11)),
 (day: date(year: 2022, month: 5, day: 8), temperature: Float(9.9))
 ]),
]
// Transformation Code
private func prepareWeeklyData() -> [WeeklyWeatherData.WeatherSeries] {
 guard let weatherData = weatherManager.weatherData else { return [] }
 
 let maxTemperatureSeries = WeeklyWeatherData.WeatherSeries(
 temperatureType: "Max Temperature",
 temperatureData: weatherData.daily.time.indices.map { index in
 (day: weatherData.daily.time[index], temperature: weatherData.daily.temperature2mMax[index])
 }
 )
 
 let minTemperatureSeries = WeeklyWeatherData.WeatherSeries(
 temperatureType: "Min Temperature",
 temperatureData: weatherData.daily.time.indices.map { index in
 (day: weatherData.daily.time[index], temperature: weatherData.daily.temperature2mMin[index])
 }
 )
 
 return [maxTemperatureSeries, minTemperatureSeries]
 }