Develop Reference

POST Request in Volley(using JSON instead of String)

I am developing an app in which i find the origin and destination of a car and send it to a server.
I know how to use volley to send an string however i am finding it hard to send data in JSON format.
Part of the code is given below:
b
tnFindPath.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
RequestQueue queue = Volley.newRequestQueue(MapsActivity.this);
String url = "http://192.168.43.162:8080/";
// Request a string response from the provided URL.
StringRequest stringRequest = new StringRequest(Request.Method.POST, url,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
}) {
//adding parameters to the request
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> params = new HashMap<>();
params.put("origin", etOrigin.getText().toString());
params.put("destination", etDestination.getText().toString());
return params;
}
};
// Add the request to the RequestQueue.
queue.add(stringRequest);

try this
final String httpUrl = //your url
try {
JSONArray parameters = new JSONArray();
JSONObject jsonObject = new JSONObject();
jsonObject.put(Key,value);
jsonObject.put(Key,value);
parameters.put(jsonObject);
Log.i(TAG,parameters.toString());
JsonArrayRequest arrayRequest = new JsonArrayRequest(Request.Method.POST, httpUrl, parametersForPhp,
new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
Log.d(TAG,response.toString());
try {
//your code
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
error.printStackTrace();
}
});
RequestQueueSingleton.getInstance(getApplicationContext()).addToRequestQueue(arrayRequest);
}catch (Exception e){
e.printStackTrace();
}
}

Android volley library POST REQUEST ERROR

Someone to help me about this error
image of my screen
thanks!

You must diklaration/adding a ErrorListener
public class MyRequest {
private Context context;
private RequestQueue queue;
public MyRequest(Context context, RequestQueue queue) {
this.context = context;
this.queue = queue;
}
public void register(String pseudo, String password, String password2) {
String url = "http://192.168.56.1/don/connexion.php";
StringRequest request = new StringRequest(Request.Method.GET, url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
}
}

Your Question about Post Request but Your Code is Get Request.......
try this for POST,
StringRequest stringRequest = new StringRequest(Request.Method.POST, REGISTER_URL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
//Success
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
//Failure
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
params.put(KEY_USERNAME, user);
params.put(KEY_PASSWORD, pass);
return params;
}
};
RequestQueue queue = Volley.newRequestQueue(getApplicationContext());
queue.add(stringRequest);
and you have to pass some params if you need to use Post method

getting error org.json.JSONException: Value <pre of type java.lang.String cannot be converted to JSONObject

I want to access my Android apps through Web-Service.
but getting error in my android app ,
i am using volley & POST method for login.. `public class Main extends AppCompatActivity implements View.OnClickListener
{
public static final String LOGIN_URL = "http://10.54.103.8:4067/evivaservices/Webservices/login";
public static final String KEY_USERNAME="username";
public static final String KEY_PASSWORD="password";
private EditText editTextUsername;
private EditText editTextPassword;
private Button buttonLogin;
private String username;
private String password;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.login_layout);
editTextUsername = (EditText) findViewById(R.id.username1);
editTextPassword = (EditText) findViewById(R.id.password1);
buttonLogin = (Button) findViewById(R.id.login_button);
buttonLogin.setOnClickListener(this);
}
private void userLogin() {
username = editTextUsername.getText().toString().trim();
password = editTextPassword.getText().toString().trim();
StringRequest stringRequest = new StringRequest(Request.Method.POST, LOGIN_URL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try
{
JSONObject jsonObject = new JSONObject(response);
Next();
}
catch(JSONException e)
{
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getApplicationContext(),error.toString(), Toast.LENGTH_LONG ).show();
}
}){
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String,String> map = new HashMap<String,String>();
map.put(KEY_USERNAME,username);
map.put(KEY_PASSWORD,password);
return map;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
private void Next(){
Intent intent = new Intent(this, HomeScreen.class);
intent.putExtra(KEY_USERNAME, username);
startActivity(intent);
}
#Override
public void onClick(View v)
{
userLogin();
}
}
`
JSON DATA
{
"id": 31,
"username": "andrew.cope#services.co.in",
"user_image": "http:\/\/103.54.103.8:4067\/evivaservices\/img\/profile_31.png",
"err-code": 0
}
`

Please change your StringRequest to JsonRequest as below:
JsonRequest jsonRequest = new JsonRequest(Request.Method.POST, LOGIN_URL, new Response.Listener<>() {
#Override
public void onResponse(Object response) {
try {
Next();
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(getApplicationContext(), error.toString(), Toast.LENGTH_LONG).show();
}
}) {
#Override
protected Map<String, String> getParams() throws AuthFailureError {
Map<String, String> map = new HashMap<String, String>();
map.put(KEY_USERNAME, username);
map.put(KEY_PASSWORD, password);
return map;
}
#Override
protected Response parseNetworkResponse(NetworkResponse response) {
return null;
}
#Override
public int compareTo(Object another) {
return 0;
}
};
Thank You.

Hello dear you made a mistake while you parsing the response
JSONArray jsonArray=jsonObject.getJSONArray("err-code")
remove above the line and then parse again.

In you JSON DATA, I not find array, so you shouldn't use JsonArray, you can delete this line in your code :JSONArray jsonArray=jsonObject.getJSONArray("err-code").

How to make separate class for volley library and call all method of volley from another activity and get response?

how to create a separate class in which define all about volley
and in another activity we directly pass URL,CONTEXT and Get Response...

First create callback interface to get result in Activity
public interface IResult {
public void notifySuccess(String requestType,JSONObject response);
public void notifyError(String requestType,VolleyError error);
}
Create a separate class with volley function to response the result through interface to activity
public class VolleyService {
IResult mResultCallback = null;
Context mContext;
VolleyService(IResult resultCallback, Context context){
mResultCallback = resultCallback;
mContext = context;
}
public void postDataVolley(final String requestType, String url,JSONObject sendObj){
try {
RequestQueue queue = Volley.newRequestQueue(mContext);
JsonObjectRequest jsonObj = new JsonObjectRequest(url,sendObj, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
if(mResultCallback != null)
mResultCallback.notifySuccess(requestType,response);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
if(mResultCallback != null)
mResultCallback.notifyError(requestType,error);
}
});
queue.add(jsonObj);
}catch(Exception e){
}
}
public void getDataVolley(final String requestType, String url){
try {
RequestQueue queue = Volley.newRequestQueue(mContext);
JsonObjectRequest jsonObj = new JsonObjectRequest(Request.Method.GET, url, new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
if(mResultCallback != null)
mResultCallback.notifySuccess(requestType, response);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
if(mResultCallback != null)
mResultCallback.notifyError(requestType, error);
}
});
queue.add(jsonObj);
}catch(Exception e){
}
}
}
Then initialize callback interface into main activity
mResultCallback = new IResult() {
#Override
public void notifySuccess(String requestType,JSONObject response) {
Log.d(TAG, "Volley requester " + requestType);
Log.d(TAG, "Volley JSON post" + response);
}
#Override
public void notifyError(String requestType,VolleyError error) {
Log.d(TAG, "Volley requester " + requestType);
Log.d(TAG, "Volley JSON post" + "That didn't work!");
}
};
Now create object of VolleyService class and pass it context and callback interface
mVolleyService = new VolleyService(mResultCallback,this);
Now call the Volley method for post or get data also pass requestType which is to identify the service requester when getting result back into main activity
mVolleyService.getDataVolley("GETCALL","http://192.168.1.150/datatest/get/data");
JSONObject sendObj = null;
try {
sendObj = new JSONObject("{'Test':'Test'}");
} catch (JSONException e) {
e.printStackTrace();
}
mVolleyService.postDataVolley("POSTCALL", "http://192.168.1.150/datatest/post/data", sendObj);
Final MainActivity
public class MainActivity extends AppCompatActivity {
private String TAG = "MainActivity";
IResult mResultCallback = null;
VolleyService mVolleyService;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
initVolleyCallback();
mVolleyService = new VolleyService(mResultCallback,this);
mVolleyService.getDataVolley("GETCALL","http://192.168.1.150/datatest/get/data");
JSONObject sendObj = null;
try {
sendObj = new JSONObject("{'Test':'Test'}");
} catch (JSONException e) {
e.printStackTrace();
}
mVolleyService.postDataVolley("POSTCALL", "http://192.168.1.150/datatest/post/data", sendObj);
}
void initVolleyCallback(){
mResultCallback = new IResult() {
#Override
public void notifySuccess(String requestType,JSONObject response) {
Log.d(TAG, "Volley requester " + requestType);
Log.d(TAG, "Volley JSON post" + response);
}
#Override
public void notifyError(String requestType,VolleyError error) {
Log.d(TAG, "Volley requester " + requestType);
Log.d(TAG, "Volley JSON post" + "That didn't work!");
}
};
}
}
Find the whole project at following link
https://github.com/PatilRohit/VolleyCallback

JsonParserVolley.java
(A separate class where we will get the response)
public class JsonParserVolley {
final String contentType = "application/json; charset=utf-8";
String JsonURL = "Your URL";
Context context;
RequestQueue requestQueue;
String jsonresponse;
private Map<String, String> header;
public JsonParserVolley(Context context) {
this.context = context;
requestQueue = Volley.newRequestQueue(context);
header = new HashMap<>();
}
public void addHeader(String key, String value) {
header.put(key, value);
}
public void executeRequest(int method, final VolleyCallback callback) {
StringRequest stringRequest = new StringRequest(method, JsonURL, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
jsonresponse = response;
Log.e("RES", " res::" + jsonresponse);
callback.getResponse(jsonresponse);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
}) {
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
return header;
}
}
;
requestQueue.add(stringRequest);
}
public interface VolleyCallback
{
public void getResponse(String response);
}
}
MainActivity.java
(Code Snippet written in onCreate method)
final JsonParserVolley jsonParserVolley = new JsonParserVolley(this);
jsonParserVolley.addHeader("Authorization", "Your value");
jsonParserVolley.executeRequest(Request.Method.GET, new JsonParserVolley.VolleyCallback() {
#Override
public void getResponse(String response) {
jObject=response;
Log.d("VOLLEY","RES"+jObject);
parser();
}
}
);
parser() is the method where the json response obtained is used to bind with the components of the activity.

you actually missed one parameter in the above VolleyService class. You needed to include, it is,...
JsonObjectRequest jsonObj = new JsonObjectRequest(Request.Method.GET, url,null,new Response.Listener() {
/..../
}
null is the parameter should be included else it gives error

Create Listeners(since they are interface they can't be instantiated but they can be instantied as an anonymous class that implement interface) inside the activity or fragment. And Pass this instances as parameters to the Request.(StringRequest, JsonObjectRequest, or ImageRequest).
public class MainActivity extends Activity {
private static final String URI = "";
// This is like BroadcastReceiver instantiation
private Listener<JSONObject> listenerResponse = new Listener<JSONObject>() {
#Override
public void onResponse(JSONObject arg0) {
// Do what you want with response
}
};
private ErrorListener listenerError = new ErrorListener() {
#Override
public void onErrorResponse(VolleyError arg0) {
// Do what you want with error
}
};
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
}
}
Next, create a class that has request and pass this listeners to this class' request method , that's all. I don't explain this part this is same as creating a request object in any tutorials.But you can customize this class as you wish. You can create singleton RequestQueue to check priority, or set body http body parameters to this methods as paremeters.
public class NetworkHandler {
public static void requestJSON(Context context, String url, Listener<JSONObject> listenerResponse, ErrorListener listenerError) {
JsonObjectRequest jsonRequest = new JsonObjectRequest(Request.Method.GET, url, null, listenerResponse, listenerError);
Volley.newRequestQueue(context).add(jsonRequest);
}
}

public class VolleyService {
IResult mResultCallback = null;
Context mContext;
VolleyService(IResult resultCallback, Context context)
{
mResultCallback = resultCallback;
mContext = context;
}
//--Post-Api---
public void postDataVolley(String url,final Map<String,String> param){
try {
StringRequest sr = new StringRequest(Request.Method.POST, url, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
if(mResultCallback != null)
mResultCallback.notifySuccessPost(response);
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
if(mResultCallback != null)
mResultCallback.notifyError(error);
}
}) {
#Override
protected Map<String, String> getParams() {
return param;
}
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
Map<String, String> params = new HashMap<String, String>();
params.put("Content-Type", "application/x-www-form-urlencoded");
return params;
}
};
AppController.getInstance(mContext).addToRequestQueue(sr);
}catch(Exception e){
}
}
//==Patch-Api==
public void patchDataVolley(String url,final HashMap<String,Object> param)
{
JsonObjectRequest request = new JsonObjectRequest(Request.Method.PATCH, url, new JSONObject(param),
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
if(mResultCallback != null)
mResultCallback.notifySuccessPatch(response);
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
if(mResultCallback != null)
mResultCallback.notifyError(error);
}
}) {
#Override
public Map<String, String> getHeaders() throws AuthFailureError {
HashMap<String, String> headers = new HashMap<String, String>();
return headers;
}
};
AppController.getInstance(mContext).addToRequestQueue(request);
}
}
public interface IResult {
void notifySuccessPost(String response);
void notifySuccessPatch(JSONObject jsonObject);
void notifyError(VolleyError error);
}

parsing Json data from server using parameters

i am new in android. i am making an application in which i am getting the data from server using volley library. but i dont know how to fetch data from server when we use id or parameters. please help.
public class MainActivity extends AppCompatActivity {
Button btn_next,btn_search,cross;
TextView title;
EditText et;
private ProgressDialog pDialog;
public static final String JSON_URL = "http://bcshymns.com/heading.php";
private Button buttonGet;
private ListView listView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
cross=(Button)findViewById(R.id.cross);
et=(EditText)findViewById(R.id.search);
btn_next=(Button)findViewById(R.id.btnnext);
btn_search=(Button)findViewById(R.id.btnsearch);
title=(TextView)findViewById(R.id.tv_title);
btn_search.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
cross.setVisibility(View.VISIBLE);
title.setVisibility(View.INVISIBLE);
et.setVisibility(View.VISIBLE);
}
});
cross.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
title.setVisibility(View.INVISIBLE);
btn_search.setVisibility(View.VISIBLE);
}
});
btn_next.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(MainActivity.this, Subheading.class);
startActivity(i);
}
});
listView = (ListView) findViewById(R.id.listView);
sendRequest();
pDialog = new ProgressDialog(this);
// Showing progress dialog before making http request
pDialog.setMessage("Loading...");
pDialog.show();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
// String product = ((TextView) view).getText().toString();
Intent i=new Intent(getApplicationContext(),Subcontent_main.class);
startActivity(i);
}
});
}
private void sendRequest(){
StringRequest stringRequest = new StringRequest(JSON_URL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
showJSON(response);
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(MainActivity.this,error.getMessage(),Toast.LENGTH_LONG).show();
}
});
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
private void showJSON(String json){
ParseJSON_Heading pj = new ParseJSON_Heading(json);
pj.parseJSON();
CustomList cl = new CustomList(this, ParseJSON_Heading.heading,ParseJSON_Heading.from,ParseJSON_Heading.to);
listView.setAdapter(cl);
hidePDialog();
}
private void hidePDialog() {
if (pDialog != null) {
pDialog.dismiss();
pDialog = null;
}
}
}`
public class ParseJSON_Heading {
public static String[] heading;
public static String[] from;
public static String[] to;
public static String[] id;
public static final String JSON_ARRAY_SUBHEADING = "tbl_heading";
public static final String JSON_ARRAY_HEADING = "tbl_heading";
public static final String KEY__HEADING_ID = "intheadingId";
public static final String KEY_TEXT_HEADING = "vchheading";
public static final String KEY_TEXT_FROM = "vchfrom";
public static final String KEY_TEXT_TO = "vchto";
private JSONArray users = null;
private String json;
public ParseJSON_Heading(String json){
this.json = json;
}
protected void parseJSON(){
JSONObject jsonObject=null;
try {
jsonObject = new JSONObject(json);
users = jsonObject.getJSONArray(JSON_ARRAY_HEADING);
id=new String[users.length()];
heading = new String[users.length()];
from = new String[users.length()];
to = new String[users.length()];
for(int i=0;i<users.length();i++){
JSONObject jo = users.getJSONObject(i);
id[i]=jo.getString(KEY__HEADING_ID);
heading[i] = jo.getString(KEY_TEXT_HEADING);
from[i] = jo.getString(KEY_TEXT_FROM);
to[i] = jo.getString(KEY_TEXT_TO);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}

If you need to submit request parameters, then you have to override the getParams() method which should return list of parameters to be sent in a key value format.
In the code below we submit name, email and password as request parameters.
JsonObjectRequest jsonObjReq = new JsonObjectRequest(Method.POST,
url, null,
new Response.Listener<JSONObject>() {
#Override
public void onResponse(JSONObject response) {
Log.d(TAG, response.toString());
pDialog.hide();
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
VolleyLog.d(TAG, "Error: " + error.getMessage());
pDialog.hide();
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
params.put("name", "foo");
params.put("email", "abc#gmail.com");
params.put("password", "foobar");
return params;
}
};