JsonObjectRequest - cannot send arguments

Question

I am not sure why I cannot get the correct response from my PHP code. For my PHP code, it is really simple. It should just return the POST arguments. But in my Android project, it returns null for all arguments. I tried to test the PHP code in my iOS project. Everything works perfect. It returns ["target": zh, "arrayString": <__NSSingleObjectArrayI 0x6000000192a0>(hello world), "source": en] So, I guess maybe my Android project has some problems then I tried to create a new project and do it again, but still hitting the same issue. Below is the steps for my new Android project.

Build Gradle

dependencies {
    compile 'com.android.volley:volley:1.1.0'
}

AndroidManifest

<uses-permission android:name="android.permission.INTERNET" />

MainActivity

import android.os.Bundle;
import android.support.v7.app.AppCompatActivity;
import android.util.Log;

import com.android.volley.Request;
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;

public class MainActivity extends AppCompatActivity {

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

        String requestString = "http://ddoommaaiinn.com/testPost.php";
        JSONObject parameters = new JSONObject();
        try {
            parameters.put("source", "en");
            parameters.put("target", "zh");
            JSONArray jsonArray = new JSONArray();
            jsonArray.put("hello world");
            parameters.put("stringArray", jsonArray);
        } catch (JSONException e) {
            e.printStackTrace();
        }

        Log.d("JSONParams", parameters.toString());

        JsonObjectRequest jsonRequest = new JsonObjectRequest(Request.Method.POST, requestString, parameters, new Response.Listener<JSONObject>() {
            @Override
            public void onResponse(JSONObject response) {
                //TODO: handle success
                Log.d("successful", response.toString());
            }
        }, new Response.ErrorListener() {
            @Override
            public void onErrorResponse(VolleyError error) {
                error.printStackTrace();
                //TODO: handle failure
            }
        });

        Volley.newRequestQueue(this).add(jsonRequest);
    }
}

Debug

12-27 08:47:19.994 4363-4363/com.pakhocheung.testjsonobjectrequest D/JSONParams: {"source":"en","target":"zh","stringArray":["hello world"]}
12-27 08:47:20.050 4363-4395/com.pakhocheung.testjsonobjectrequest D/NetworkSecurityConfig: No Network Security Config specified, using platform default
12-27 08:47:20.079 4363-4397/com.pakhocheung.testjsonobjectrequest D/OpenGLRenderer: HWUI GL Pipeline
12-27 08:47:20.885 4363-4397/com.pakhocheung.testjsonobjectrequest I/zygote: android::hardware::configstore::V1_0::ISurfaceFlingerConfigs::hasWideColorDisplay retrieved: 0
12-27 08:47:20.886 4363-4397/com.pakhocheung.testjsonobjectrequest I/OpenGLRenderer: Initialized EGL, version 1.4
12-27 08:47:20.886 4363-4397/com.pakhocheung.testjsonobjectrequest D/OpenGLRenderer: Swap behavior 1
12-27 08:47:20.886 4363-4397/com.pakhocheung.testjsonobjectrequest W/OpenGLRenderer: Failed to choose config with EGL_SWAP_BEHAVIOR_PRESERVED, retrying without...
12-27 08:47:20.886 4363-4397/com.pakhocheung.testjsonobjectrequest D/OpenGLRenderer: Swap behavior 0
12-27 08:47:20.892 4363-4397/com.pakhocheung.testjsonobjectrequest D/EGL_emulation: eglCreateContext: 0xa6f859e0: maj 2 min 0 rcv 2
12-27 08:47:20.895 4363-4397/com.pakhocheung.testjsonobjectrequest D/EGL_emulation: eglMakeCurrent: 0xa6f859e0: ver 2 0 (tinfo 0xb050d880)
12-27 08:47:20.998 4363-4397/com.pakhocheung.testjsonobjectrequest D/EGL_emulation: eglMakeCurrent: 0xa6f859e0: ver 2 0 (tinfo 0xb050d880)
12-27 08:47:21.279 4363-4363/com.pakhocheung.testjsonobjectrequest D/successful: {"source":null,"target":null,"arrayString":null}

PHP code

<?php
$source = $_POST['source'];
$target = $_POST['target'];
$arrayString = $_POST['stringArray'];
echo json_encode(array('source'=>$source,'target'=>$target,'arrayString'=>$arrayString));
?>

Answer 1

When using a JsonObjectRequest the desired data would be found in php://input as a (json) string. To get that data do:

<?php
$postArray = json_decode(file_get_contents('php://input'), true);

// now you access the values nearly as before:
$source = $postArray['source'];
$target = $postArray['target'];
$arrayString = $postArray['arrayString'];

echo json_encode(array('source'=>$source,'target'=>$target,'arrayString'=>$arrayString));
?>