我的 JsonObjectRequest POST 请求不起作用？

如何解决我的 JsonObjectRequest POST 请求不起作用？

我正在尝试使用 MysqL 数据库中的数据填充 Spinner。

public void getData() {
    /*To add parameters & values for the request*/
    Map < String,String > params = new HashMap < > ();
    params.put("Email",sessionemail);

    JSONObject parameters = new JSONObject(params);

    /*Create ArrayList to store vehicle_id to later get vehicle data from DB Query*/
    ArrayList < String > vehicleid = new ArrayList < > ();
    ArrayList < String > tagList = new ArrayList < > ();

    /*Initialize Json Object Request*/
    JsonObjectRequest jsonObjectRequest = new JsonObjectRequest(Request.Method.POST,URL,parameters,response - > {
        try {
            //Parsing the fetched Json String to JSON Object
            JSONArray jsonArray = response.getJSONArray("tags");
            Log.d(String.valueOf(jsonArray),"JSON DATA");
            for (int i = 0; i < jsonArray.length(); i++) {
                JSONObject jsonObject = jsonArray.getJSONObject(i);
                String tag = jsonObject.optString("Tag");
                String vehicle = jsonObject.optString("Vehicle_Id");
                tagList.add(tag);
                vehicleid.add(vehicle);
                tagidAdapter = new ArrayAdapter < > (Alert.this,android.R.layout.simple_spinner_item,tagList);
                tagidAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
                tagSpinner.setAdapter(tagidAdapter);
            }
        } catch (JSONException e) {
            e.printstacktrace();
        }
    },Throwable::getStackTrace);

    /*Adding request to the queue*/
    requestQueue.add(jsonObjectRequest);
}

以下是我通过执行 GET 请求从 PHP 中获取的数据：

{
    "tags": [{
        "Tag": "W1C6EZY583DB2907X4A","Vehicle_Id": "4"
    },{
        "Tag": "6QZL43YEWR6IMMFUING","Vehicle_Id": "6"
    },{
        "Tag": "STK6WQ8ONDOUMEFSGQF","Vehicle_Id": "17"
    },{
        "Tag": "93RPHOC8M2AAQ2P2TUX","Vehicle_Id": "72"
    },{
        "Tag": "UH31KR4F6EFGHJ33S82","Vehicle_Id": "73"
    }]
}

所以基本上我需要的是将“标签”值插入到微调器中，但是由于某种原因，当我到达 jsonObjectRequest 时，请求失败了。

解决方法

更改为 StringRequest，这解决了我的问题。

    StringRequest strRequest = new StringRequest(Request.Method.POST,URL,new Response.Listener<String>()
            {
                @Override
                public void onResponse(String response)
                {
                    JSONArray jsonArray = null;

                    try {
                        jsonArray = new JSONArray(response);
                        for (int i = 0; i < jsonArray.length(); i++) {
                            JSONObject jsonObject = jsonArray.getJSONObject(i);
                            String tag = jsonObject.optString("Tag");
                            String vehicle = jsonObject.optString("Vehicle_Id");
                            tagList.add(tag);
                            vehicleid.add(vehicle);
                            tagidAdapter = new ArrayAdapter<>(Alert.this,android.R.layout.simple_spinner_item,tagList);
                            tagidAdapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
                            tagSpinner.setAdapter(tagidAdapter);
                        }
                    } catch (JSONException e) {
                        e.printStackTrace();
                    }


                }
            },