有人可以帮助将 URLSession 从 Swift 转换为 Kotlin

如何解决有人可以帮助将 URLSession 从 Swift 转换为 Kotlin

我想用 Kotlin 制作多平台天气应用程序。而且我还想在通用模块中为 Android 和 iOS 分别获取天气数据。

使用 Android 我没有任何问题，但使用 iOS 部分我有。我想使用 Foundation 框架通过 URLSession 获取和序列化数据。但它不起作用。

这是我的天气模型。

    package com.example.weatherappversion3.shared

    data class WeatherData (
        val cod: String,val message: Long,val cnt: Long,val list: List<ListElement>,val city: City
    )
    
    data class City (
        val id: Long,val name: String,val coord: Coord,val country: String,val population: Long,val timezone: Long,val sunrise: Long,val sunset: Long
    )
    
    data class Coord (
        val lat: Double,val lon: Double
    )
    
    data class ListElement (
        val dt: Long,val main: MainClass,val weather: List<Weather>,val clouds: Clouds,val wind: Wind,val visibility: Long,val pop: Double,val sys: Sys,val dtTxt: String,val snow: Rain? = null,val rain: Rain? = null
    )
    
    data class Clouds (
        val all: Long
    )
    
    data class MainClass (
        val temp: Double,val feelsLike: Double,val temp_min: Double,val temp_max: Double,val pressure: Long,val seaLevel: Long,val grndLevel: Long,val humidity: Long,val tempKf: Double
    )
    
    data class Rain (
        val the3H: Double
    )
    
    data class Sys (
        val pod: Pod
    )
    
    enum class Pod {
        D,N
    }
    
    data class Weather (
        val id: Long,val main: MainEnum,val description: String,val icon: String
    )
    
    enum class MainEnum {
        Clear,Clouds,Rain,Snow
    }
    
    data class Wind (
        val speed: Double,val deg: Long,val gust: Double
    )

这是我的要求：

    package com.example.weatherappversion3.shared

    import com.example.weatherappversion3.shared.constants.Constants
    //import cocoapods.Alamofire.*
    import platform.Foundation.*
    import platform.darwin.NSObject
    
    //import SwiftyJSON
    
    actual class WeatherManager {

    actual var weatherData: WeatherData? = null
    var data = NSData()
    //https://api.openweathermap.org/data/2.5/forecast?appid=e83bce43f40758140ef6927fda5cfc85&units=metric&lat=48.51320000&lon=32.25970000
    var url = "https://api.openweathermap.org/data/2.5/forecast?appid=${Constants().AppId}&units=${Constants().units}&lat=${Constants().lat}&lon=${Constants().lon}"
    actual fun getWeatherForecastFor(updateUI: ()->Unit) {
        println("Start request for iOS")
        asyncRequest(url)
        updateUI()
    }

    fun asyncRequest(url: String) {

        val delegate = object : NSObject(),NSURLSessionDataDelegateProtocol {

            override fun URLSession(session: NSURLSession,dataTask: NSURLSessionDataTask,didReceiveData: NSData) {
                data = didReceiveData
            }

            override fun URLSession(session: NSURLSession,task: NSURLSessionTask,didCompleteWithError: NSError?) {
                val response = task.response
                if (response == null || (response as NSHTTPURLResponse).statusCode.toInt() != 200) {
                    return
                }

                if (didCompleteWithError != null) {
                    return
                }

            }
        }

        val session = NSURLSession.sessionWithConfiguration(
            NSURLSessionConfiguration.defaultSessionConfiguration(),delegate,delegateQueue = NSOperationQueue.mainQueue()
        )

        session.dataTaskWithURL(NSURL(string = url)).resume()
    }

    actual fun getWeatherForecastForSpecialCity(city: String) {

    }

}

解决方法

Kotlinx serialization 是目前推荐的多平台序列化方式，它支持 js、native 和 jvm 目标

Here you can see kotlinx 序列化示例

,

在纯 iOS 中，您可以对数据使用 Codable 协议，或者使用 Foundation 框架中的 JSONDecoder 类手动解码。

Kotlin 的等价物是 Gson。可能还有其他解决方案。

编辑：是的，还有其他解决方案，请参阅 Kotlinx（感谢 @joffrey 的评论）- https://github.com/Kotlin/kotlinx.coroutines

    data class WeatherData (
        @SerializedName("cod_key")  // Optional field name
        val cod: String,val message: Long,val cnt: Long,val list: List<ListElement>,val city: City
    )

    didReceiveData() {
        val weather = Gson().fromJson<WeatherData>(data,WeatherData::class.java)
    }

https://github.com/google/gson