Error parsing data JSON, Fragment Android Studio - json

Question

Someone please help me why my result always error parsing data ?
My app run smoothly but does not display anything. i feel so stuck here.
this is my code
Sorry for bad english
API JSON
public function getkategori2(){
$data = array();
$token = $this->input->post('f_token');
$tabel = $this->input->post('f_tabel');
if ($token == '' || $tabel == ''){
$data['result'] = false;
$data['msg'] = "Data Kosong";
echo json_encode($data);
return;
}
$sql = 'SELECT * FROM '.$tabel.'_kategori INNER JOIN files WHERE '.$tabel.'_kategori.id_kategori = files.id_kategori';
$q = $this->db->query($sql);
if ($q->num_rows()>0) {
foreach ($q->result() as $value) {
$kategori = array(
'nama_kategori' => $value->nama_kategori,
'file_name' => $value->file_name,
);
};
$data['result'] = true;
$data['kategori_data'] = $kategori;
$data['msg'] = '';
} else {
$data['result'] = false;
$data['msg'] = 'error';
}
echo json_encode($data);
}
JSON Result
{
"result":true,
"kategori_data":
{
"nama_kategori":"Pasta",
"file_name":"1_Pasta.jpg"
},
"msg":""
}
KategoriAdapter
public class KategoriAdapter extends RecyclerView.Adapter<KategoriAdapter.ViewHolder> {
private ArrayList<Kategori> mData;
private Context context;
private SessionManager sesi;
public KategoriAdapter (Context context, ArrayList<Kategori> mData){
this.context = context;
this.mData = mData;
}
#Override
public KategoriAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType){
View view = LayoutInflater.from(context)
.inflate(R.layout.item_list_kategori, parent, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(KategoriAdapter.ViewHolder holder, int position) {
Kategori k = mData.get(position);
String kategori = k.getKategoriNama();
String gambar = k.getImg();
//masukan kedalam object viewholder
holder.tvKategori.setText(kategori);
Picasso.with(context)
.load(Constant.BASE_IMAGE + sesi.getTabel() + "/kategori/" + gambar)
.into(holder.ivKategori);
}
//buta object interface onAdapterjabatanListener
private OnAdapterListener listener;
//buat method untuk mendefiniskan listenernya
public void setListener(OnAdapterListener listener){
this.listener = listener;
}
#Override
public int getItemCount() {
return mData == null ? 0 : mData.size();
}
//buat class yang extend dari ViewHolder
class ViewHolder extends RecyclerView.ViewHolder{
public LinearLayout container;
public TextView tvKategori;
public ImageView ivKategori;
public ViewHolder(View v){
super(v);
//baru hubungkan variablenya dengan item yang ada di class layout item
container = v.findViewById(R.id.container);
tvKategori = v.findViewById(R.id.tvKategori);
ivKategori = v.findViewById(R.id.ivKategori);
}
}
KategoriFragment
public class KategoriFragment extends Fragment {
SessionManager sesi;
private ArrayList<Kategori> data;
private OkHttpClient okClient;
private RecyclerView rvData;
public KategoriFragment() {
// Required empty public constructor
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate the layout for this fragment
View rootView = inflater.inflate(R.layout.fragment_kategori, container, false);
sesi = new SessionManager(getActivity());
data = new ArrayList<>();
okClient = new OkHttpClient();
rvData = rootView.findViewById(R.id.rvData);
RecyclerView.LayoutManager manager = new LinearLayoutManager(getActivity());
rvData.setLayoutManager(manager);
getData();
return rootView;
}
private void getData(){
data.clear();
String url = Constant.BASE_URL + "getkategori2";
FormBody parameters = new FormBody.Builder()
.add("f_token", sesi.getToken())
.add("f_tabel", sesi.getTabel())
.build();
//buat request untuk ambil data
Request request = new Request.Builder()
.url(url)
.post(parameters)
.build();
okClient.newCall(request).enqueue(new Callback() {
#Override
public void onFailure(Call call, final IOException e) {
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
e.printStackTrace();
RbHelpers.pesan(getActivity(),
"error :" + e.getMessage());
}
});
}
#Override
public void onResponse(Call call,final Response response) throws IOException {
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
//hilangkan dialognya
}});
final String responData = response.body().string();
RbHelpers.pre("respon data : " + responData);
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
//debug hasilnya kedalam android monitor
try {
//parsing json
try {
JSONObject json = new JSONObject(responData);
Log.d("tagJSON",json.toString());
//check hasilnya apakah true or false
boolean hasil = json.getBoolean("result");
if (hasil){
//ada datanya
//buat object jsonArray
JSONArray jArray = json.getJSONArray("kategori_data");
//looping data dan masukkan kedalam arraylist
for (int i = 0; i < jArray.length(); i++){
JSONObject jObj = jArray.getJSONObject(i);
Kategori kategori = new Kategori();
kategori.setKategoriNama(jObj.getString("nama_kategori"));
kategori.setImg(jObj.getString("file_name"));
//tinggal masukan ke arraylist
data.add(kategori);
}
} else {
String msg = json.getString("msg");
RbHelpers.pesan(getActivity(), msg);
}
//tinggal masukin ke recylerview
//UserAdapter adapter = new UserAdapter
KategoriAdapter adapter = new KategoriAdapter(getActivity(), data);
rvData.setAdapter(adapter);
} catch (JSONException e){
RbHelpers.pesan(getActivity(), "Error parsing data");
e.printStackTrace();
}
} catch (Exception e) {
RbHelpers.pesan(getActivity(), "Error ambil data");
e.printStackTrace();
}
}
});
}
});
}

Answer 1

Think this is the wrong part "kategori_data" is a JSONObject , not a JSONArray, Check the correct format in jsonBlob as
Here you have an example of a mine working project where i have a model Articulo(Product) and I make a request to retrieve that object data
try{
// Get the JSON array
JSONObject result = response.getJSONObject("articulo");
int i ;
for(i=0;i<1;i++){
JSONObject articulo = result;
ListaArticulos item = new ListaArticulos(
articulo.getString("IdArticulo"),
articulo.getString("Precio"),
articulo.getString("Stock"),
articulo.getString("Consultas"),
articulo.getString("IdCategoria"),
articulo.getString("Descripcion"),
articulo.getString("Observacion"),
articulo.getString("Codigo"),
articulo.getString("Imagen")
);
So in conclusion what you need to do is change JSONArray jArray = json.getJSONArray("kategori_data");
for
JSONObject jsonOb = json.getJSONObject("kategori_data");