I'm trying to return JSONArray on my method.

I want to see

String test = getremseat("20220827", "0671801", "3112001").toString();`        
Log.i("test", test);'

but result is I/test: []

I think getremseat method does not return because of queue.add(req); how can I return JSONArray from the method using Volley?

MainActivity.java:

package com.example.terapi3;

import androidx.appcompat.app.AppCompatActivity;

import android.os.Bundle;
import android.util.Log;


import com.android.volley.AuthFailureError;
import com.android.volley.Request;
import com.android.volley.RequestQueue;
import com.android.volley.Response;
import com.android.volley.VolleyError;
import com.android.volley.toolbox.JsonObjectRequest;

import com.android.volley.toolbox.Volley;

import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;

import java.util.HashMap;
import java.util.Map;


public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate (Bundle savedInstanceState){
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        String test = getremseat("20220827", "0671801", "3112001").toString();
        Log.i("test", test);
    }

    public JSONArray getremseat (String timDte, String terFrI, String terToI) {
     /*
        String timDte = "20220826";
        String terFrI = "0671801";
        String terToI = "3112001";
    */

        JSONArray ja = new JSONArray();

        // GET requset url
        String url = "https://apigw.tmoney.co.kr:5556/gateway/xzzIbtListGet/v1";
        String timTimI = "0000";  //

        RequestQueue queue = Volley.newRequestQueue(this);


        JsonObjectRequest req = new JsonObjectRequest(Request.Method.GET, url   "/ibt_list"   "/"   timDte   "/"   timTimI   "/"   terFrI   "/"   terToI   "/9/0",
                null, new Response.Listener<JSONObject>() {

            @Override
            public void onResponse(JSONObject response) {

                try {
                    JSONArray jsonArray = response.getJSONObject("response").getJSONArray("LINE_LIST");


                    for (int a = 0; a < jsonArray.length(); a  ) {
                        JSONObject jo = jsonArray.getJSONObject(a);

                        JSONObject joo = new JSONObject();
                        joo.put("TIM_TIM", jo.getString("TIM_TIM"));
                        joo.put("LIN_TIM", jo.getString("LIN_TIM"));
                        joo.put("REM_CNT", jo.getString("REM_CNT"));

                        ja.put(joo);

                    }
                    

                } catch (JSONException e) {
                    e.printStackTrace();
                }
            }

        }, new Response.ErrorListener() {
            @Override
            public void one rrorResponse(VolleyError error) {
                Log.e("e", "Site Info Error: "   error.getMessage());
            }
        }) {
            // header
            @Override
            public Map<String, String> getHeaders() throws AuthFailureError {
                HashMap<String, String> headers = new HashMap<String, String>();
                headers.put("x-Gateway-APIKey", "MY PERSONAL KEY");
                return headers;
            }


        };


        queue.add(req);
        return ja; // i want to return this
    }

}

And, I also want return JSONArray to other package.

CodePudding user response：

You're getting an empty JSONArray because you're logging in before the API gives the response.

You can solve this problem by making a callback method to call after you get the API response.

Example

onCreate

private String test = "";

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    getremseat("20220827", "0671801", "3112001").toString();
}

getremseat

. . .

for (int a = 0; a < jsonArray.length(); a  ) {
      JSONObject jo = jsonArray.getJSONObject(a);

      JSONObject joo = new JSONObject();
      joo.put("TIM_TIM", jo.getString("TIM_TIM"));
      joo.put("LIN_TIM", jo.getString("LIN_TIM"));
      joo.put("REM_CNT", jo.getString("REM_CNT"));
      ja.put(joo);
}
test = ja.toString(); <-----
onResult(ja);         <-----

. . .

onResult

public void onResult (JSONArray jsonArray){
    Log.d("tag", jsonArray.toString());
}