com.android.volley.parseerror org.json.jsonexception value yes of type java.lang.String cannot be converted to JSONObject

Question

I want to get data from php file after putting the value m (String) in JSONObject and give result in TextView ie mResultTextView . However, this is giving me the following error.

com.android.volley.parseerror org.json.jsonexception value yes of type java.lang.String cannot be converted to JSONObject

var m = barcode.displayValue.toString()
val jsonobj = JSONObject()

jsonobj.put("email", m)
val url = "http://192.168.1.106/verf1.php"
val que = Volley.newRequestQueue(this@MainActivity)

val req = JsonObjectRequest(Request.Method.POST, url, jsonobj, Response.Listener {
    response -> mResultTextView.text = response.toString()
},Response.ErrorListener {
    response -> mResultTextView.text = response.toString()
})
que.add(req)

Answer 1

You need to set the content-type to application/json in the header for your POST request. For adding a custom header along with your POST request you might consider taking a look at this tutorial .

I am copying the code example from the tutorial from the link above.

class ServiceVolley : ServiceInterface {
    val TAG = ServiceVolley::class.java.simpleName
    val basePath = "https://your/backend/api/"

    override fun post(path: String, params: JSONObject, completionHandler: (response: JSONObject?) -> Unit) {
        val jsonObjReq = object : JsonObjectRequest(Method.POST, basePath + path, params,
                Response.Listener<JSONObject> { response ->
                    Log.d(TAG, "/post request OK! Response: $response")
                    completionHandler(response)
                },
                Response.ErrorListener { error ->
                    VolleyLog.e(TAG, "/post request fail! Error: ${error.message}")
                    completionHandler(null)
                }) {
            @Throws(AuthFailureError::class)
            override fun getHeaders(): Map<String, String> {
                val headers = HashMap<String, String>()
                headers.put("Content-Type", "application/json")
                return headers
            }
        }

        BackendVolley.instance?.addToRequestQueue(jsonObjReq, TAG)
    }
}