I am working on an android application. In this application, I have to retrieve data from a web service and put it in a listview, but it is not retrieving anything. I don't know what I am doing wrong here. Maybe someone can help me with this.
Webservice: http://10.247.240.53/kas/lampen.php
Mainactivity:
`
public class MainActivity extends AppCompatActivity {
ListView listView;
ArrayAdapter<String> adapter;
String[] data;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
listView = findViewById(R.id.listview);
StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder().permitNetwork().build());
getData();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Intent intent = new Intent(MainActivity.this, Showdata.class);
intent.putExtra("teeltbed", listView.getItemAtPosition(position).toString());
startActivity(intent);
}
});
}
private void getData()
{
String getData = null;
String dbResult = "empty";
dbConnect database = new dbConnect(this);
try{
String query = "SELECT * FROM Lamp";
getData = "?query=" + URLEncoder.encode(query, "UTF-8");
String link = "http://10.247.240.53/kas/lampen.php";
dbResult = database.execute(link).get();
}
catch (Exception e){
}
try{
JSONArray ja = new JSONArray(dbResult);
JSONObject jo = null;
data = new String[ja.length()];
for (int i = 0; i < ja.length(); i++)
{
jo = ja.getJSONObject(i);
data[i] = jo.getString("teeltbed");
}
adapter = new ArrayAdapter<String>(this, R.layout.layout_list, R.id.list_item, data);
listView.setAdapter(adapter);
}
catch (Exception e)
{
e.printStackTrace();
}
}
}`
Related
I am trying to code a recipe app, I am pulling the recipes from an online JSON file.
Therefore I needed a custom ArrayAdapter and now I want to filter the List.
But as it turns out the adapter can't get the Filter function. I looked up other articles but none of them were helpful. Hope somebody can help out in this case.
This is the tutorial I watched to code online JSON to ListView: https://www.youtube.com/watch?v=v4X0y6-VOtM
Here is my Code:
public class Food_choosing_menu extends Fragment {
private ListView lv;
SearchView searchView;
ListAdapter adapter;
String name,time;
private static String JSON_URL = "https://---.github.io/---.json";
ArrayList<HashMap<String, String>> recepieList;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View v = inflater.inflate(R.layout.fragment_food_choosing_menu, container, false);
recepieList = new ArrayList<>();
lv = v.findViewById(R.id.Food_List_View);
searchView = v.findViewById(R.id.Searh_bar_food);
GetData getData = new GetData();
getData.execute();
return v;
}
public class GetData extends AsyncTask<String, String, String>{
#Override
protected String doInBackground(String... strings) {
String current = "";
try {
URL url;
HttpURLConnection urlConnection = null;
try {
url = new URL(JSON_URL);
urlConnection = (HttpURLConnection) url.openConnection();
InputStream inputStream = urlConnection.getInputStream();
InputStreamReader inputStreamReader = new InputStreamReader(inputStream);
int data = inputStreamReader.read();
while (data != -1) {
current += (char) data;
data = inputStreamReader.read();
}
return current;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
}
}catch (Exception e){
e.printStackTrace();
}
return current;
}
#Override
protected void onPostExecute(String s) {
try {
JSONObject jsonObject = new JSONObject(s);
JSONArray jsonArray = jsonObject.getJSONArray("Recepies");
for (int i = 0; i< jsonArray.length(); i++){
JSONObject jsonObject1 = jsonArray.getJSONObject(i);
name = jsonObject1.getString("name");
time = jsonObject1.getString("time");
HashMap<String, String> recepies = new HashMap<>();
recepies.put("name", name);
recepies.put("time", time);
recepieList.add(recepies);
}
}catch (JSONException e){
e.printStackTrace();
}
adapter = new SimpleAdapter(
getContext(),
recepieList,
R.layout.row_layout,
new String[] {"name", "time"},
new int[]{R.id.textView1});
lv.setAdapter(adapter);
lv.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
Toast.makeText(getContext(), "You Click -"+adapter.getItem(position).toString(), Toast.LENGTH_SHORT).show();
}
});
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String query) {
return false;
}
#Override
public boolean onQueryTextChange(String newText) {
return false;
}
});
}
}
i am trying to send Data (ID value) from one activity to other
but it wouldn't send correct data , i want it to send only ID Value of Clicked Item to next activity , here is my code
public class Order extends AppCompatActivity {
private ListView lvUsers;
private ProgressDialog dialog;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_sub);
dialog = new ProgressDialog(this);
dialog.setIndeterminate(true);
dialog.setCancelable(false);
dialog.setMessage("Loading, please wait.....");
lvUsers = (ListView) findViewById(R.id.lvUsers);
new JSONTask().execute("http://146.185.178.83/resttest/order");
}
public class JSONTask extends AsyncTask<String, String, List<OrderModel> > {
#Override
protected void onPreExecute(){
super.onPreExecute();
dialog.show();
}
#Override
protected List<OrderModel> doInBackground(String... params) {
HttpURLConnection connection = null;
BufferedReader reader = null;
try {
URL url = new URL(params[0]);
connection = (HttpURLConnection) url.openConnection();
connection.connect();
InputStream stream = connection.getInputStream();
reader = new BufferedReader(new InputStreamReader(stream));
StringBuffer buffer = new StringBuffer();
String line ="";
while ((line=reader.readLine()) !=null){
buffer.append(line);
}
String finalJson = buffer.toString();
JSONArray parentArray = new JSONArray(finalJson);
List<OrderModel> orderModelList = new ArrayList<>();
Gson gson = new Gson();
for (int i = 0; i < parentArray.length(); i++) {
JSONObject finalObject = parentArray.getJSONObject(i);
OrderModel orderModel = gson.fromJson(finalObject.toString(), OrderModel.class);
orderModelList.add(orderModel);
}
return orderModelList;
}catch (MalformedURLException e) {
e.printStackTrace();
}catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
} finally {
if(connection !=null) {
connection.disconnect();
}
try {
if (reader !=null) {
reader.close();
}
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
#Override
protected void onPostExecute(List<OrderModel> result) {
super.onPostExecute(result);
dialog.dismiss();
OrderAdapter adapter = new OrderAdapter(getApplicationContext(), R.layout.row_order, result);
lvUsers.setAdapter(adapter);
}
}
public class OrderAdapter extends ArrayAdapter {
public List<OrderModel> orderModelList;
private int resource;
private LayoutInflater inflater;
public OrderAdapter(Context context, int resource, List<OrderModel> objects) {
super(context, resource, objects);
orderModelList = objects;
this.resource = resource;
inflater = (LayoutInflater) getSystemService(LAYOUT_INFLATER_SERVICE);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
ViewHolder holder = null;
if(convertView == null){
holder = new ViewHolder();
convertView=inflater.inflate(resource, null);
holder.bOrderNo = (Button) convertView.findViewById(R.id.bOrderNo);
convertView.setTag(holder);
}else {
holder = (ViewHolder) convertView.getTag();
}
final int orderId = orderModelList.get(position).getId();
holder.bOrderNo.setText("Order No: " + orderModelList.get(position).getOrderId());
holder.bOrderNo.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(Order.this, OrderSelected.class);
intent.putExtra("parameter_name", orderId);
startActivity(intent);
}
});
return convertView;
}
class ViewHolder{
private Button bOrderNo;
}
}
}
The holder gets executed in loop i guess is why it wouldn't send right Id.
How do i get it to send only Id of the clicked orderId
you can check this link to see how json Response looks like http://146.185.178.83/resttest/order
You have a silly mistake in your code . I have edited single line in your code . I think you are getting same "orderId" every time instead of actual "orderId". Check this one . I hope your problem will resolve .
final int index = position;
holder.bOrderNo.setText("Order No: " + orderModelList.get(position).getOrderId());
holder.bOrderNo.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Intent intent = new Intent(Order.this, OrderSelected.class);
intent.putExtra("parameter_name", orderModelList.get(index).getId());
startActivity(intent);
}
});
Please try
In place of
intent.putExtra("parameter_name", orderId);
Please put
intent.putExtra("parameter_name", orderModelList.get(position).getId());
The problem is that whenever the user go to the third fragment then coming back to the first one, all the data in the first fragment will be gone.
the Data will parsed from a web service, using AsyncTask within the fragment
this my onCreate() method
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
int radius = 4;
double latitude = 51.3674718208489;
double longtitude = -0.119329656538836;
Boolean loyal = false;
int mer = 1;
try {
parameters.put(ConstantKeys.SEARCH_NAME, searchname);
parameters.put(ConstantKeys.LOYALTY, isLoyalty);
Log.d(CommunityFragment.class.getSimpleName(), parameters.toString());
} catch (JSONException e) {
e.printStackTrace();
}
FindOfferField();
}
this is my onCreateView() method
public View onCreateView(LayoutInflater inflater,
ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.community_fragment, container, false);
return rootView;
}
and this is my AsynTask()
public void FindOfferField() {
RegisterRequest request = new RegisterRequest(getActivity());
SharedPreferences userpass = getActivity().getSharedPreferences("USERPASS", 0);
String email = userpass.getString("username", null);
String password = userpass.getString("password", null);
Log.d(CommunityFragment.class.getSimpleName(), "Email:" + email + " Password:" + password);
request.getToken(email, password, new ApiRequestListener() {
#Override
public void onSuccess(Object object) {
(new FindOfferTask() {
#Override
protected void onPostExecute(JSONObject data) {
super.onPostExecute(data);
try {
if (data.getString(ConstantKeys.RESULT).equals("OK")) {
array = data.getJSONArray(ConstantKeys.RESULTS);
RowItem items;
rowItem = new ArrayList<RowItem>();
for (int i = 0; i < array.length(); i++) {
final JSONObject list = array.getJSONObject(i);
items = new RowItem();
int id = Integer.parseInt(offerList.getString("Id"));
byID = id;
Log.d("AnotherID", String.valueOf(byID));
Boolean isCommunity = offerList.getBoolean(ConstantKeys.IS_COMMUNITY);
items.setId(list.getInt("Id"));
items.setMerchantid(list.getInt(ConstantKeys.MERCHANTID));
items.setDescription(list.getString(ConstantKeys.DESCRIPTION));
items.setDateEnd(list.getString(ConstantKeys.DATE).replace("T00:00:00", ""));
items.setTokensFor(list.getString(ConstantKeys.FOR));
if (!offerList.isNull("ImageId")) {
int bitmapImageID = offerList.getInt("ImageId");
Log.d("BITMAPHAHA", String.valueOf(bitmapImageID));
items.setImageId(bitmapImageID);
}
rowItem.add(items);
listView = (ListView) getView().findViewById(R.id.listViewCommunity);
adapter = new CustomListAdapter(getActivity(), rowItem);
adapter.notifyDataSetChanged();
listView.setAdapter(adapter);
getEndTask = new RowItemLoyalty();
getTask = new RowItem();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
boolean isCommunity = false;
try {
isCommunity = offerList.getBoolean(ConstantKeys.IS_COMMUNITY);
} catch (JSONException e) {
e.printStackTrace();
}
int ID = rowItem.get(position).getId();
int merID = rowItem.get(position).getMerchantid();
Intent intent = new Intent(getActivity(), CustomerPromotion.class);
getEndTask.endTask();
getTask.endTask();
intent.putExtra("ID", ID);
intent.putExtra("MERCHANT", merID);
intent.putExtra("BOOLEANVALUE", isCommunity);
startActivity(intent);
}
});
}
Log.d("JSON Data", data.toString());
}
} catch (JSONException e) {
e.printStackTrace();
}
Log.d("JSON DATA", data.toString());
Log.w("Success Register", data.toString());
}
}).execute();
}
#Override
public void onError(String error) {
Log.e("Registration Error", error);
}
});
}
UPDATE
public class CommunityFragment extends ListFragment{
//LocationListener location;
ProgressDialog progressDialog;
Context context;
public static JSONObject parameters = new JSONObject();
private static final String STATE_LIST = "State Adapter Data";
public static final String DATA = "DATA";
public CustomerAccount customerAccount;
//---------Find Parameters----------
int byID;
//CustomListAdapter adapter;
public static String TAG = CommunityFragment.class.getSimpleName();
ListView listView;
ArrayList<RowItem> rowItem;
View view;
private static final String ARG_PARAM1 = "param1";
private static final String ARG_PARAM2 = "param2";
String searchname = ConstantSearch.SEARCHNAME;
CustomListAdapter adapter;
private String mParam1;
private String mParam2;
RowItemLoyalty getEndTask;
RowItem getTask;
RowItem storeData;
int index;
int top;
JSONArray array;
public CommunityFragment() {
}
public static CommunityFragment newInstance(String param1, String param2) {
CommunityFragment fragment = new CommunityFragment();
Bundle args = new Bundle();
args.putString(ARG_PARAM1, param1);
args.putString(ARG_PARAM2, param2);
fragment.setArguments(args);
return fragment;
}
#Override
public void onSaveInstanceState(Bundle outState) {
super.onSaveInstanceState(outState);
String dataInJson = new Gson().toJson(rowItem);
outState.putString(DATA, dataInJson);
super.onSaveInstanceState(outState);
}
#Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
if(savedInstanceState != null && savedInstanceState.containsKey(DATA))
{
Log.d("StringData", DATA);
String jsonData = savedInstanceState.getString(DATA);
rowItem = new Gson().fromJson(jsonData, new TypeToken<List<RowItem>>(){}.getType());
}
else
{
rowItem = new ArrayList<>();
}
adapter = new CustomListAdapter(getActivity(), rowItem);
listView.setAdapter(adapter);
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
if (getArguments() != null) {
mParam1 = getArguments().getString(ARG_PARAM1);
mParam2 = getArguments().getString(ARG_PARAM2);
}
int radius = 4;
double latitude = 51.3674718208489;
double longtitude = -0.119329656538836;
Boolean isLoyalty = false;
int mer = 1;
try {
parameters.put(ConstantKeys.SEARCH_NAME, searchname);
parameters.put(ConstantKeys.LOYALTY, isLoyalty);
Log.d(CommunityFragment.class.getSimpleName(), parameters.toString());
} catch (JSONException e) {
e.printStackTrace();
}
FindOfferField();
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.community_fragment, container, false);
rowItem = new ArrayList<RowItem>();
listView = (ListView) rootView.findViewById(R.id.listViewCommunity);
return rootView;
}
public interface OnFragmentInteractionListener {
void onFragmentInteraction(Uri uri);
}
public void FindOfferField() {
RegisterRequest request = new RegisterRequest(getActivity());
SharedPreferences userpass = getActivity().getSharedPreferences("USERPASS", 0);
String email = userpass.getString("username", null);
String password = userpass.getString("password", null);
Log.d(CommunityFragment.class.getSimpleName(), "Email:" + email + " Password:" + password);
request.getToken(email, password, new ApiRequestListener() {
#Override
public void onSuccess(Object object) {
(new FindOfferTask() {
#Override
protected void onPostExecute(JSONObject data) {
super.onPostExecute(data);
try {
if (data.getString(ConstantKeys.RESULT).equals("OK")) {
array = data.getJSONArray(ConstantKeys.RESULTS);
RowItem items;
rowItem = new ArrayList<RowItem>();
for (int i = 0; i < array.length(); i++) {
final JSONObject offerList = array.getJSONObject(i);
items = new RowItem();
int id = Integer.parseInt(offerList.getString("Id"));
byID = id;
Log.d("AnotherID", String.valueOf(byID));
Boolean isCommunity = offerList.getBoolean(ConstantKeys.IS_COMMUNITY);
items.setId(offerList.getInt("Id"));
items.setMerchantid(offerList.getInt(ConstantKeys.FAVORITE_MERCHANTID));
items.setDescription(offerList.getString(ConstantKeys.DESCRIPTION));
items.setDateEnd(offerList.getString(ConstantKeys.DATE_END).replace("T00:00:00", ""));
items.setTokensFor(offerList.getString(ConstantKeys.TOKENSFOR));
if (!offerList.isNull("ImageId")) {
int bitmapImageID = offerList.getInt("ImageId");
Log.d("BITMAPHAHA", String.valueOf(bitmapImageID));
items.setImageId(bitmapImageID);
}
rowItem.add(items);
adapter = new CustomListAdapter(getActivity(), rowItem);
listView.setAdapter(adapter);
adapter.notifyDataSetChanged();
getEndTask = new RowItemLoyalty();
getTask = new RowItem();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
boolean isCommunity = false;
try {
isCommunity = offerList.getBoolean(ConstantKeys.IS_COMMUNITY);
} catch (JSONException e) {
e.printStackTrace();
}
int offerID = rowItem.get(position).getId();
int merID = rowItem.get(position).getMerchantid();
Intent intent = new Intent(getActivity(), CustomerPromotion.class);
getEndTask.endTask();
getTask.endTask();
intent.putExtra("ID", offerID);
intent.putExtra("MERCHANT", merID);
intent.putExtra("BOOLEANVALUE", isCommunity);
startActivity(intent);
}
});
}
Log.d("JSON Data", data.toString());
}
} catch (JSONException e) {
e.printStackTrace();
}
Log.d("JSON DATA", data.toString());
Log.w("Success Register", data.toString());
}
}).execute();
}
#Override
public void onError(String error) {
Log.e("Registration Error", error);
}
});
}
public class FindOfferTask extends AsyncTask<Void, Void, JSONObject> {
#Override
protected void onPreExecute() {
super.onPreExecute();
progressDialog = new ProgressDialog(getActivity());
progressDialog.setMessage("Loading...");
progressDialog.setCancelable(false);
progressDialog.show();
}
#Override
protected JSONObject doInBackground(Void... params) {
ApiSecurityManager manager = ApiSecurityManager.getInstance();
String result = manager.apiCall("Offers/find", parameters.toString(), "C");
Log.d(CommunityFragment.class.getSimpleName(), result);
JSONObject jsonResult = new JSONObject();
Log.i(getClass().getSimpleName(), result);
try
{
jsonResult = new JSONObject(result);
}
catch (JSONException e)
{
e.printStackTrace();
}
return jsonResult;
}
protected void onPostExecute(JSONObject jsonObject) {
//loadingMore = false;
progressDialog.dismiss();
}
}
}
First of all, keep your view creation outside ApiRequestListener. Initialize all views in onCreateView() only.
// Key for storing data in `savedInstance`
public static final String DATA = "DATA";
In onCreateView()
public View onCreateView(LayoutInflater inflater,
ViewGroup container,
Bundle savedInstanceState) {
View rootView = inflater.inflate(R.layout.community_fragment, container, false);
rowItem = new ArrayList<RowItem>();
listView = (ListView) rootView.findViewById(R.id.listViewCommunity);
return rootView;
}
When activity is created, check if data is available in savedInstanceState or not and based on that start web service.
#Override
public void onActivityCreated(Bundle savedInstanceState)
{
super.onActivityCreated(savedInstanceState);
if(savedInstanceState.containsKey(DATA))
{
String jsonData = savedInstanceState.getString(DATA);
rowItem = new Gson().fromJson(jsonData, new TypeToken<List<RowItem>>(){}.getType());
}
else
{
rowItem = new ArrayList<>();
}
adapter = new CustomListAdapter(getActivity(), rowItem);
listView.setAdapter(adapter);
// Now here, check the size of array list. If it is 0, then start service to fetch data from server
}
To convert your list into string, I am using Gson library here.
#Override
public void onSaveInstanceState(Bundle outState)
{
// Here use gson library from google to convert list of data to string.
String dataInJson = new Gson().toJson(rowItem);
outState.putString(DATA, dataInJson);
super.onSaveInstanceState(outState);
}
And your method will look like this:
public void FindOfferField() {
RegisterRequest request = new RegisterRequest(getActivity());
SharedPreferences userpass = getActivity().getSharedPreferences("USERPASS", 0);
String email = userpass.getString("username", null);
String password = userpass.getString("password", null);
Log.d(CommunityFragment.class.getSimpleName(), "Email:" + email + " Password:" + password);
request.getToken(email, password, new ApiRequestListener() {
#Override
public void onSuccess(Object object) {
(new FindOfferTask() {
#Override
protected void onPostExecute(JSONObject data) {
super.onPostExecute(data);
try {
if (data.getString(ConstantKeys.RESULT).equals("OK")) {
array = data.getJSONArray(ConstantKeys.RESULTS);
RowItem items;
for (int i = 0; i < array.length(); i++) {
final JSONObject list = array.getJSONObject(i);
items = new RowItem();
int id = Integer.parseInt(offerList.getString("Id"));
byID = id;
Log.d("AnotherID", String.valueOf(byID));
Boolean isCommunity = offerList.getBoolean(ConstantKeys.IS_COMMUNITY);
items.setId(list.getInt("Id"));
items.setMerchantid(list.getInt(ConstantKeys.MERCHANTID));
items.setDescription(list.getString(ConstantKeys.DESCRIPTION));
items.setDateEnd(list.getString(ConstantKeys.DATE).replace("T00:00:00", ""));
items.setTokensFor(list.getString(ConstantKeys.FOR));
if (!offerList.isNull("ImageId")) {
int bitmapImageID = offerList.getInt("ImageId");
Log.d("BITMAPHAHA", String.valueOf(bitmapImageID));
items.setImageId(bitmapImageID);
}
rowItem.add(items);
adapter.notifyDataSetChanged();
getEndTask = new RowItemLoyalty();
getTask = new RowItem();
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
boolean isCommunity = false;
try {
isCommunity = offerList.getBoolean(ConstantKeys.IS_COMMUNITY);
} catch (JSONException e) {
e.printStackTrace();
}
int ID = rowItem.get(position).getId();
int merID = rowItem.get(position).getMerchantid();
Intent intent = new Intent(getActivity(), CustomerPromotion.class);
getEndTask.endTask();
getTask.endTask();
intent.putExtra("ID", ID);
intent.putExtra("MERCHANT", merID);
intent.putExtra("BOOLEANVALUE", isCommunity);
startActivity(intent);
}
});
}
Log.d("JSON Data", data.toString());
}
} catch (JSONException e) {
e.printStackTrace();
}
Log.d("JSON DATA", data.toString());
Log.w("Success Register", data.toString());
}
}).execute();
}
#Override
public void onError(String error) {
Log.e("Registration Error", error);
}
});
}
Hope this helps.
ChooseCategory.java
public class ChooseCategory extends ListActivity {
private ListView lv;
//ArrayAdapter<FoodStores> arrayAdapter;
private ArrayList<FoodStores> storefoodList;
private String URL_STORES = "http://10.0.2.2/get_stores.php";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
lv = (ListView)findViewById(R.id.list);
storefoodList = new ArrayList<FoodStores>();
new GetFoodStores().execute();
}
private class GetFoodStores extends AsyncTask<Void,Void,Void> {
#Override
protected void onPreExecute(){
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... arg0) {
ServiceHandlerFood jsonParserFood = new ServiceHandlerFood();
String json = jsonParserFood.makeServiceCall(URL_STORES, ServiceHandlerFood.GET);
Log.e("Response: ", " > " + json);
if(json != null){
try{
JSONObject jsonObj = new JSONObject(json);
if(jsonObj != null){
JSONArray storeListFood = jsonObj.getJSONArray("storelistfood");
for(int i = 0; i < storeListFood.length(); i++){
JSONObject storeFoodObj = (JSONObject) storeListFood.get(i);
FoodStores foodStores = new FoodStores(storeFoodObj.getInt("id"),storeFoodObj.getString("STORENAME"));
storefoodList.add(foodStores);
}
}
}catch(JSONException e){
e.printStackTrace();
}
}else{
Log.e("JSON Data", "No data received from server");
}
return null;
}
#Override
protected void onPostExecute(Void result){
super.onPostExecute(result);
populateListView();
}
}
Here is the function of my populateListView
private void populateListView(){
List<String> labels = new ArrayList<String>();
for(int i = 0; i < storefoodList.size(); i++){
labels.add(storefoodList.get(i).getName());
}
ArrayAdapter<String> listAdapter = new ArrayAdapter<String>(this,R.layout.restaurant_list,labels);
Log.d("Labels:", labels.toString());
lv.setAdapter(listAdapter);
}
What I am trying to do here is to get the list of stores from PHP to Android via JSON and store them in ArrayList and then populate them into ListView. I have tried displaying labels, it is displaying the correct stuff.
The error from Emulator is that it just shows blank screen and then it crashes.
The error from logcat is
java.lang.NullPointerException
at call.rocket.user.callarocket.ChooseCategory.populateListView
Do like
ArrayAdapter<String> listAdapter = new ArrayAdapter<String>(this,R.layout.restaurant_list,labels);
setListAdapter(listAdapter);
as you directly extends ListActivity also remove
lv = (ListView)findViewById(R.id.list);
and make sure your ListView id is android:id="#android:id/list"
Go to Tutorial
I'm trying to pass an Arraylist with Objects obtained from a JSON, and pass to another fragment in Android Studio.
Here is the class that i want to receive the array
#Override
public View onCreateView(LayoutInflater inflater,
ViewGroup container,
Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.fragment_car, container, false);
new AsyncTaskParseJson().execute();
mRecyclerView = (RecyclerView) view.findViewById(R.id.rv_list);
mRecyclerView.setHasFixedSize(true);
mRecyclerView.addOnItemTouchListener(new RecyclerViewTouchListener( getActivity(), mRecyclerView, this ));
LinearLayoutManager llm = new LinearLayoutManager(getActivity());
llm.setOrientation(LinearLayoutManager.VERTICAL);
mRecyclerView.setLayoutManager(llm);
CarAdapter adapter = new CarAdapter(getActivity(), mList);
mRecyclerView.setAdapter( adapter );
return view;
}
That is my class that is creating the array:
public class AsyncTaskParseJson extends AsyncTask<String, String, String> {
final String TAG = "AsyncTaskParseJson.java";
String yourJsonStringUrl = "http://marciowelben.servidorturbo.net/getjson.php";
JSONArray dataJsonArr = null;
#Override
protected void onPreExecute() {}
#Override
protected String doInBackground(String... arg0) {
try {
JsonParser jParser = new JsonParser();
JSONObject json = jParser.getJSONFromUrl(yourJsonStringUrl);
dataJsonArr = json.getJSONArray("emp_info");
for (int i = 0; i < dataJsonArr.length(); i++) {
JSONObject c = dataJsonArr.getJSONObject(i);
// Storing each json item in variable
String firstname = c.getString("employee name");
String lastname = c.getString("employee no");
Car d = new Car(firstname, lastname, R.mipmap.ic_launcher );
listAux.add(d);
}
} catch (JSONException e) {
e.printStackTrace();
}
mList = listAux;
return null;
}
}
So i just want to populate my Recyclerview with this array.
Since you are adding the adapter first before waiting for the data to return you will have to call notifyDataSetChanged() for the adapter to redraw the list after it is done parsing. Another way of accomplishing this is waiting for the result to come back and then set the adapter. See below
public class MainActivity extends AppCompatActivity {
private static final String TAG = "RecyclerViewExample";
private List<FeedItem> feedItemList = new ArrayList<FeedItem>();
private RecyclerView mRecyclerView;
private MyRecyclerAdapter adapter;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
/* Initialize recyclerview */
mRecyclerView = (RecyclerView) findViewById(R.id.recycler_view);
mRecyclerView.setLayoutManager(new LinearLayoutManager(this));
/*Downloading data from below url*/
final String url = "http://javatechig.com/api/get_category_posts/?dev=1&slug=android";
new AsyncHttpTask().execute(url);
}
public class AsyncHttpTask extends AsyncTask<String, Void, Integer> {
#Override
protected void onPreExecute() {
setProgressBarIndeterminateVisibility(true);
}
#Override
protected Integer doInBackground(String... params) {
InputStream inputStream = null;
Integer result = 0;
HttpURLConnection urlConnection = null;
try {
/* forming th java.net.URL object */
URL url = new URL(params[0]);
urlConnection = (HttpURLConnection) url.openConnection();
/* for Get request */
urlConnection.setRequestMethod("GET");
int statusCode = urlConnection.getResponseCode();
/* 200 represents HTTP OK */
if (statusCode == 200) {
BufferedReader r = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
StringBuilder response = new StringBuilder();
String line;
while ((line = r.readLine()) != null) {
response.append(line);
}
parseResult(response.toString());
result = 1; // Successful
}else{
result = 0; //"Failed to fetch data!";
}
} catch (Exception e) {
Log.d(TAG, e.getLocalizedMessage());
}
return result; //"Failed to fetch data!";
}
#Override
protected void onPostExecute(Integer result) {
setProgressBarIndeterminateVisibility(false);
/* Download complete. Lets update UI */
if (result == 1) {
adapter = new MyRecyclerAdapter(MainActivity.this, feedItemList);
mRecyclerView.setAdapter(adapter);
} else {
Log.e(TAG, "Failed to fetch data!");
}
}
}
private void parseResult(String result) {
try {
JSONObject response = new JSONObject(result);
JSONArray posts = response.optJSONArray("posts");
/*Initialize array if null*/
if (null == feedItemList) {
feedItemList = new ArrayList<FeedItem>();
}
for (int i = 0; i < posts.length(); i++) {
JSONObject post = posts.optJSONObject(i);
FeedItem item = new FeedItem();
item.setTitle(post.optString("title"));
item.setThumbnail(post.optString("thumbnail"));
feedItemList.add(item);
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
1.Design Recycleview in layout
<android.support.v7.widget.RecyclerView
android:id="#+id/recycler_view"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingTop="10dp"
android:layout_weight="1"
/>
2.add dependency in gradle.build
compile 'com.android.support:recyclerview-v7:23.1.1'
3.Write the code in Activity
public class DoctorInformationActivity extends AppCompatActivity {
String URL="YOUR URL";
JSONArray Cities=null;
ArrayList<DocotorInformation> doctorList =new ArrayList<DocotorInformation>();
Sqlitedatabase sql;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.doctor_information_listview);
sql=new Sqlitedatabase(getApplicationContext());
ConnectivityManager connectivityManager
= (ConnectivityManager) getSystemService(Context.CONNECTIVITY_SERVICE);
NetworkInfo activeNetworkInfo = connectivityManager.getActiveNetworkInfo();
if(activeNetworkInfo != null && activeNetworkInfo.isConnected())
{
Toast.makeText(getApplicationContext()," connect",Toast.LENGTH_LONG).show();
new JSONAsyncTask().execute();
}
else
{
ArrayList<DocotorInformation> listdata=sql.getAllContacts();
doctorList=listdata;
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
DoctorAdapter mAdapter = new DoctorAdapter(getApplicationContext(), doctorList);
recyclerView.setAdapter(mAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
Toast.makeText(getApplicationContext(),"Not connect",Toast.LENGTH_LONG).show();
}
}
private class JSONAsyncTask extends AsyncTask<String, Void, JSONArray> {
private ProgressDialog dialog = new ProgressDialog(DoctorInformationActivity.this);
#Override
protected void onPreExecute() {
this.dialog.setMessage("Please wait");
this.dialog.show();
}
#Override
protected JSONArray doInBackground(String... urls) {
try {
//------------------>>
HttpGet httppost = new HttpGet(URL);
HttpClient httpclient = new DefaultHttpClient();
HttpResponse response = httpclient.execute(httppost);
// StatusLine stat = response.getStatusLine();
int status = response.getStatusLine().getStatusCode();
if (status == 200) {
HttpEntity entity = response.getEntity();
String data = EntityUtils.toString(entity);
JSONObject jsono = new JSONObject(data);
Cities = jsono.getJSONArray("SearchDoctorsData");
return Cities;
}
} catch (IOException e) {
e.printStackTrace();
} catch (JSONException e) {
e.printStackTrace();
}
return Cities;
}
protected void onPostExecute(JSONArray result) {
dialog.dismiss();
System.out.println(result);
for (int i = 0; i < result.length(); i++) {
JSONObject c = null;
try {
DocotorInformation doc=new DocotorInformation();
c = result.getJSONObject(i);
doc.setName(c.getString("DoctorName"));
doc.setNumber(c.getString("Mobile"));
doctorList.add(doc);
sql.insertData(doc);
} catch (JSONException e) {
e.printStackTrace();
}
}
RecyclerView recyclerView = (RecyclerView) findViewById(R.id.recycler_view);
DoctorAdapter mAdapter = new DoctorAdapter(getApplicationContext(), doctorList);
recyclerView.setAdapter(mAdapter);
recyclerView.setLayoutManager(new LinearLayoutManager(getApplicationContext()));
}
}
}
public class DoctorAdapter extends RecyclerView.Adapter<DoctorAdapter.ViewHolder> {
private ArrayList<DocotorInformation> countries;
Context con;
public DoctorAdapter(Context c ,ArrayList<DocotorInformation> countries) {
this.con=c;
this.countries = countries;
}
#Override
public DoctorAdapter.ViewHolder onCreateViewHolder(ViewGroup viewGroup, int i) {
View view = LayoutInflater.from(viewGroup.getContext()).inflate(R.layout.doctor_textviews, viewGroup, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(DoctorAdapter.ViewHolder viewHolder, int i) {
viewHolder.name.setText(countries.get(i).getName());
viewHolder.number.setText(countries.get(i).getNumber());
}
#Override
public int getItemCount() {
return countries.size();
}
public class ViewHolder extends RecyclerView.ViewHolder{
private TextView name,number;
public ViewHolder(View view) {
super(view);
name = (TextView)view.findViewById(R.id.name);
number = (TextView)view.findViewById(R.id.numebr);
}
}
}