我想根据Java和Kotlin提出简单的Volley POST请求。我在应用程序中同时使用两种语言,因此我尽力使用两种语言。
我在Kotlin的以下VolleyClass中浏览了this教程:

WolfRequest(val url class:String,
                  val结果:(JSONObject)-> Unit,
                  val错误:(字符串)->单位){

fun POST(vararg params: Pair<String, Any>) {
    // HashMap to pass arguments to Volley
    val hashMap = HashMap<String, String>()
    params.forEach {
        // Convert all Any type to String and add to HashMap
        hashMap[it.first] = it.second.toString()
    }
    // Make the Http Request
    makeRequest(Request.Method.POST, hashMap)
}

private fun makeRequest(method: Int, params: HashMap<String, String>) {
    // Creating a StringRequest
    val req = object : StringRequest(method, url, { res ->

        // Creating JSON object from the response string
        // and passing it to result: (JSONObject) -> Unit function
        result(JSONObject(res.toString().trim()))
    }, { volleyError ->

        // Getting error message and passing it
        // to val error: (String) -> Unit function
        error(volleyError.message!!)
    }) {
        // Overriding getParams() to pass our parameters
        override fun getParams(): MutableMap<String, String> {
            return params
        }
    }

    // Adding request to the queue
    volley.add(req)
}

// For using Volley RequestQueue as a singleton
// call WolfRequest.init(applicationContext) in
// app's Application class
companion object {
    var context: Context? = null
    val volley: RequestQueue by lazy {
        Volley.newRequestQueue(context
                ?: throw NullPointerException(" Initialize WolfRequest in application class"))
    }

    fun init(context: Context) {
        this.context = context
    }
}


}

我正在尝试从Java.Class访问此代码以进行POST请求:

    WolfRequest.Companion.init(getApplicationContext());
    HashMap <String, String> params = new HashMap <> ();
    params.put("id", "123");

    new WolfRequest(config.PING_EVENTS,*new WolfRequest()*
    {

        public void response(JSONObject response) {
            Log.e("Ping","PING");
        }

        public void error(String error) {
            Log.e("Ping",error);
        }
    }).POST(params);


它给我一个错误(新WolfRequest()),它说:无法从最终的“ ... wolfrequest.kt”继承

我确实没有收到错误,这是什么问题?

谢谢

最佳答案

默认情况下,kotlin中的类是最终的。要创建无最终类,您需要将其声明为open。所以open class WolfRequest

在Java中使用new WolfRequest() {}可以创建扩展WolfRequest的匿名类,因此您将从继承的类继承该错误。

要实际调用WolfRequest的构造函数,您需要传递三个参数。就像是:

new WolfRequest("", (s) -> Unit.INSTANCE, (s) -> Unit.INSTANCE){
....
}

08-18 12:27