Volley String 无法转换为 JSONObject

Question

只要我将数组放入Params，我总是会收到以下错误。即使在转换为 String 之后，它仍然会出现该错误。代码在没有 contactlist 数组的情况下工作正常。有什么想法吗？

错误

com.android.volley.ParseError: org.json.JSONException: Value Created of type java.lang.String cannot be converted to JSONObject

响应示例：

{
"username": "test2",
"lists": [
    "contact_0",
    "contact_1",
    "contact_2",
    "contact_3",
    "contact_4",
    "contact_5",
    "contact_6",
    "contact_7",
    "contact_8",
    "contact_9"
]
}

ArrayList<String> contactList = new ArrayList<String>();
public String joinInfo;


Cursor phones = getContentResolver().query(ContactsContract.CommonDataKinds.Phone.CONTENT_URI, null,null,null, null);
        while (phones.moveToNext())
        {
            String name=phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.DISPLAY_NAME));
            String phoneNumber = phones.getString(phones.getColumnIndex(ContactsContract.CommonDataKinds.Phone.NUMBER));
            System.out.println("name : " + name + ", ID : " + phoneNumber);
            joinInfo = name;
            contactList.add(joinInfo);
        }
        phones.close();

 RequestQueue rq = Volley.newRequestQueue(this);

        JSONObject params = new JSONObject();
        try {
            params.put("username", "test2");
            params.put("lists", contactList.toString()); // When i change this to simply "test" a string, it works fine.
            Log.d("PANDA", contactList.toString());
        } catch (JSONException e) {
            e.printStackTrace();
        }

        JsonObjectRequest jsonObjReq = new JsonObjectRequest(Request.Method.POST,
                "http://postcatcher.in/catchers/55521f03f708be0300001d28", params, //Not null.
                new Response.Listener<JSONObject>() {

                    @Override
                    public void onResponse(JSONObject response) {
                        Log.d("PANDA", response.toString());
                    }
                }, new Response.ErrorListener() {

            @Override
            public void onErrorResponse(VolleyError error) {
                VolleyLog.d("PANDA", "Error: " + error.getMessage());
                Log.d("PANDA", error.toString());
            }
        });

        // Adding request to request queue
        rq.add(jsonObjReq);

Answer 1

PostCatcher 虽然允许我们 post 请求，但它的响应基本上是一个普通字符串 "Created" 而不是 Json 格式。因此，我们的客户端代码无法确定它并抛出错误。一件事是即使没有带有普通 (String, String) K,V 对的 ArrayList 对象，它也会失败。

如果您尝试通过Advanced Rest Client发送请求，您可以验证它（见附件）

Volley String 无法转换为 JSONObject

Volley String cannot be converted to JSONObject

java

arrays

android

json

android-volley