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How Do We Set id For Data That Showed With Volley Json Array Request

I have some problem about setting and getting id from data that showed with volley JSon array request.
I've tried to do this, but it fail.
ChildTidur.java
public class ChildTidur extends AppCompatActivity implements TidurAdapter.ContactsAdapterListener {
private static final String TAG = ChildTidur.class.getSimpleName();
private RecyclerView recyclerView;
private List<Story> storyList;
private TidurAdapter mAdapter;
private SearchView searchView;
private TextView noFavtsTV;
private AppPreferences appPreferences;
// CONNECTION_TIMEOUT and READ_TIMEOUT are in milliseconds
public static final int CONNECTION_TIMEOUT = 2000;
public static final int READ_TIMEOUT = 2000;
final String KEY_SAVED_RADIO_BUTTON_INDEX = "SAVED_RADIO_BUTTON_INDEX";
// url to fetch contacts json
private static final String URL = "https://api.kafeinkode.com/childtidur.json";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.child_tidur);
AppCompatDelegate.setCompatVectorFromResourcesEnabled(true);
SwipeRefreshLayout pullToRefresh = findViewById(R.id.pullToRefresh);
pullToRefresh.setOnRefreshListener(new SwipeRefreshLayout.OnRefreshListener() {
#Override
public void onRefresh() {
finish();
startActivity(getIntent());
}
});
//toolbar logo and desc
Toolbar topToolBar = (Toolbar) findViewById(R.id.toolbarTidur);
setSupportActionBar(topToolBar); //munculkan menu ke toolbar
getSupportActionBar().setDisplayHomeAsUpEnabled(true); //this line shows back button
recyclerView = findViewById(R.id.recycler_view);
noFavtsTV = findViewById(R.id.no_favt_text);
storyList = new ArrayList<>();
mAdapter = new TidurAdapter(this, storyList, this, appPreferences);
// white background notification bar
whiteNotificationBar(recyclerView);
RecyclerView.LayoutManager mLayoutManager = new LinearLayoutManager(getApplicationContext());
recyclerView.setLayoutManager(mLayoutManager);
recyclerView.setItemAnimator(new DefaultItemAnimator());
recyclerView.addItemDecoration(new TidurDekor(this, DividerItemDecoration.VERTICAL, 36));
recyclerView.setAdapter(mAdapter);
//Make call to AsyncTask
new AsyncLogin().execute();
//Get radio button value
LoadPreferences();
} //OnCreate
private void showNoFavtText(boolean show) {
noFavtsTV.setVisibility(show ? View.VISIBLE : View.GONE); //jika data yang ditampilkan tidak ada, maka show noFavsTv
recyclerView.setVisibility(show ? View.GONE : View.VISIBLE); //jika data yang ditampilkan tidak ada, maka don't show rV
}
private void LoadPreferences(){
LayoutInflater inflater = (LayoutInflater) this.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View contentView = inflater.inflate(R.layout.activity_settings, null,false);
RadioGroup radioGroup = (RadioGroup)contentView.findViewById(R.id.radioSex);
SharedPreferences sharedPreferences = getSharedPreferences("MY_SHARED_PREF", MODE_PRIVATE);
int savedRadioIndex = sharedPreferences.getInt(KEY_SAVED_RADIO_BUTTON_INDEX, 0);
RadioButton savedCheckedRadioButton = (RadioButton)radioGroup.getChildAt(savedRadioIndex);
savedCheckedRadioButton.setChecked(true);
RadioGroup genderGroup = (RadioGroup) contentView.findViewById(R.id.radioSex);
RadioButton male = (RadioButton) contentView.findViewById(R.id.theme1);
RadioButton female = (RadioButton) contentView.findViewById(R.id.theme2);
if (genderGroup.getCheckedRadioButtonId() == -1) {
Toolbar tb = (Toolbar) findViewById(R.id.toolbarTidur);
tb.setBackgroundColor(getResources().getColor(R.color.colorPrimaryDark));
}
else {
if (male.isChecked()) { // one of the radio buttons is checked
Toolbar tb1 = (Toolbar) findViewById(R.id.toolbarTidur);
tb1.setBackgroundColor(getResources().getColor(R.color.colorPrimaryDark));
}
else if (female.isChecked()) {
Toolbar tb2 = (Toolbar) findViewById(R.id.toolbarTidur);
tb2.setBackgroundColor(getResources().getColor(R.color.colorAccent));
}
}
}
private class AsyncLogin extends AsyncTask<String, String, String> {
ProgressDialog pdLoading = new ProgressDialog(ChildTidur.this);
HttpURLConnection conn;
java.net.URL url = null;
#Override
protected void onPreExecute() {
super.onPreExecute();
//this method will be running on UI thread
showNoFavtText(false);
pdLoading.setMessage("\tMencoba terhubung ke internet...");
pdLoading.setCancelable(false);
pdLoading.show();
}
#Override
protected String doInBackground(String... params) {
try {
// Enter URL address where your json file resides
// Even you can make call to php file which returns json data
url = new URL("https://api.kafeinkode.com/childtidur.json");
} catch (MalformedURLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
return e.toString();
}
try {
// Setup HttpURLConnection class to send and receive data from php and mysql
conn = (HttpURLConnection) url.openConnection();
conn.setReadTimeout(READ_TIMEOUT);
conn.setConnectTimeout(CONNECTION_TIMEOUT);
conn.setRequestMethod("GET");
// setDoOutput to true as we recieve data from json file
conn.setDoOutput(true);
} catch (IOException e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
return e1.toString();
}
try {
int response_code = conn.getResponseCode();
// Check if successful connection made
if (response_code == HttpURLConnection.HTTP_OK) {
// Read data sent from server
InputStream input = conn.getInputStream();
BufferedReader reader = new BufferedReader(new InputStreamReader(input));
StringBuilder result = new StringBuilder();
String line;
while ((line = reader.readLine()) != null) {
result.append(line);
}
// Pass data to onPostExecute method
return (result.toString());
} else {
return("koneksi gagal");
}
} catch (IOException e) {
e.printStackTrace();
return e.toString();
} finally {
conn.disconnect();
}
}
/**
* fetches json by making http calls
*/
protected void onPostExecute(String result) {
JsonArrayRequest request = new JsonArrayRequest(URL, new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
pdLoading.dismiss();
Log.d(TAG, response.toString());
if (response.length() > 0) {
// Parsing json
List<Story> items = new Gson().fromJson(response.toString(), new TypeToken<List<Story>>() {
}.getType());
// adding contacts to contacts list
storyList.clear();
storyList.addAll(items);
// refreshing recycler view
mAdapter.notifyDataSetChanged();
for (int i=0; i<storyList.size(); i++) {
Story story = new Story();
story.setIdStory(String.valueOf(i));
}
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
pdLoading.dismiss();
// error in getting json
Log.e(TAG, "Error: " + error.getMessage());
Toast.makeText(getApplicationContext(), "Tidak bisa menampilkan data. Periksa kembali sambungan internet Anda", Toast.LENGTH_LONG).show();
AlertDialog alertDialog = new AlertDialog.Builder(ChildTidur.this).create();
alertDialog.setTitle("Error");
alertDialog.setMessage("Data Tidak bisa ditampilkan. Periksa kembali sambungan internet Anda");
alertDialog.setButton(AlertDialog.BUTTON_NEUTRAL, "OK",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
alertDialog.show();
showNoFavtText(true);
}
});
TidurSearch.getInstance().addToRequestQueue(request);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.search_tidur, menu);
getMenuInflater().inflate(R.menu.menu_main, menu);
// Associate searchable_tidur configuration with the SearchView
SearchManager searchManager = (SearchManager) getSystemService(Context.SEARCH_SERVICE);
searchView = (SearchView) menu.findItem(R.id.action_search2).getActionView();
searchView.setSearchableInfo(searchManager
.getSearchableInfo(getComponentName()));
searchView.setMaxWidth(Integer.MAX_VALUE);
// listening to search query text change
searchView.setOnQueryTextListener(new SearchView.OnQueryTextListener() {
#Override
public boolean onQueryTextSubmit(String query) {
// filter recycler view when query submitted
mAdapter.getFilter().filter(query);
return false;
}
#Override
public boolean onQueryTextChange(String query) {
// filter recycler view when text is changed
mAdapter.getFilter().filter(query);
return false;
}
});
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
//noinspection SimplifiableIfStatement
if (id == R.id.action_search2) {
return true;
}
//Menu
if (id == R.id.action_settings) {
startActivity(new Intent(this, SettingsActivity.class));
return true;
}
else
if (id == R.id.about_us) {
startActivity(new Intent(this, AboutUs.class));
return true;
}
else
if (id == R.id.favlist) {
startActivity(new Intent(this, ShowFavouriteList.class));
return true;
}
switch (item.getItemId()) {
case android.R.id.home:
this.finish();
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public void onBackPressed() {
// close search view on back button pressed
if (!searchView.isIconified()) {
searchView.setIconified(true);
return;
}
super.onBackPressed();
}
private void whiteNotificationBar(View view) {
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
int flags = view.getSystemUiVisibility();
flags |= View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR;
view.setSystemUiVisibility(flags);
getWindow().setStatusBarColor(Color.WHITE);
}
}
#Override
public void onContactSelected(Story story) {
Toast.makeText(getApplicationContext(), "Selected: " + story.getName(), Toast.LENGTH_LONG).show();
}
}
TidurAdapter.java
public void onClick(View view) {
// Another problem lays here when I get id of data
Story story = storyList.get(getLayoutPosition());
int ambilId = Integer.parseInt(story.getIdStory());
if ( 0 == ambilId ) {
Intent myIntent = new Intent(view.getContext(), DoaMauTidur.class);
view.getContext().startActivity(myIntent);
}
else if ( 1 == getAdapterPosition() )
{
Intent myIntent = new Intent(view.getContext(), DoaBangunt.class);
view.getContext().startActivity(myIntent);
}
else if ( 2 == getAdapterPosition() )
{
Intent myIntent = new Intent(view.getContext(), DoaJimak.class);
view.getContext().startActivity(myIntent);
}
}
This is a full code:
Story.java
public Story(){}
String name;
String nomor;
private String idStory;
private int isLiked;
public String getName() {
return name;
}
public String getNomor() { return nomor; }
public void setIdStory(String isStory) {
this.idStory = isStory;
}
public String getIdStory() {
return idStory;
}
public void setIsLiked(int isLiked) {
this.isLiked = isLiked;
}
public int getIsLiked() {
return isLiked;
}
}
ChildTidur.java
/**
* fetches json by making http calls
*/
protected void onPostExecute(String result) {
JsonArrayRequest request = new JsonArrayRequest(URL, new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
pdLoading.dismiss();
Log.d(TAG, response.toString());
if (response.length() > 0) {
// Parsing json
List<Story> items = new Gson().fromJson(response.toString(), new TypeToken<List<Story>>() {
}.getType());
// adding contacts to contacts list
storyList.clear();
storyList.addAll(items);
// refreshing recycler view
mAdapter.notifyDataSetChanged();
for (int i=0; i<storyList.size(); i++) {
Story story = new Story();
story.setIdStory(String.valueOf(i));
}
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
pdLoading.dismiss();
// error in getting json
Log.e(TAG, "Error: " + error.getMessage());
Toast.makeText(getApplicationContext(), "Tidak bisa menampilkan data. Periksa kembali sambungan internet Anda", Toast.LENGTH_LONG).show();
AlertDialog alertDialog = new AlertDialog.Builder(ChildTidur.this).create();
alertDialog.setTitle("Error");
alertDialog.setMessage("Data Tidak bisa ditampilkan. Periksa kembali sambungan internet Anda");
alertDialog.setButton(AlertDialog.BUTTON_NEUTRAL, "OK",
new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int which) {
dialog.dismiss();
}
});
alertDialog.show();
showNoFavtText(true);
}
});
TidurSearch.getInstance().addToRequestQueue(request);
}
}
TidurAdapter.java
public class TidurAdapter extends RecyclerView.Adapter<TidurAdapter.TidurViewHolder> implements Filterable {
private Context context;
private List<Story> storyList;
private List<Story> storyListFiltered;
private ContactsAdapterListener listener;
private int changedItemPosition;
public boolean isLiked;
private AppPreferences appPreferences;
Boolean checked = false;
public TidurAdapter(Context context, List<Story> storyList, ContactsAdapterListener listener, AppPreferences appPreferences) {
this.context = context;
this.listener = listener;
this.storyList = storyList;
this.storyListFiltered = storyList;
this.appPreferences = appPreferences;
}
#Override
public TidurViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View itemView = LayoutInflater.from(parent.getContext()).inflate(R.layout.child_row_item_tidur, parent, false);
return new TidurViewHolder(itemView);
}
#Override
public void onBindViewHolder(#NonNull TidurViewHolder holder, int position) {
final Story story = storyListFiltered.get(position);
holder.name.setText(story.getName());
holder.nomor.setText(story.getNomor());
holder.setViewData(storyList.get(position), holder.getAdapterPosition());
}
#Override
public int getItemCount() {
return storyListFiltered.size();
}
public interface ContactsAdapterListener {
void onContactSelected(Story story);
}
//ViewHolder
public class TidurViewHolder extends RecyclerView.ViewHolder {
public TextView name;
public TextView nomor;
public ImageView mFavorite;
private CheckBox likeCheckBox;
final String KEY_SAVED_RADIO_BUTTON_INDEX = "SAVED_RADIO_BUTTON_INDEX";
public TidurViewHolder(View view) {
super(view);
name = view.findViewById(R.id.name);
nomor = view.findViewById(R.id.nomor);
likeCheckBox = itemView.findViewById(R.id.like_button_cb);
view.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
// get id of data
Story story = storyList.get(getLayoutPosition());
int ambilId = Integer.parseInt(story.getIdStory());
if ( 0 == ambilId ) {
Intent myIntent = new Intent(view.getContext(), DoaMauTidur.class);
view.getContext().startActivity(myIntent);
}
else if ( 1 == getAdapterPosition() )
{
Intent myIntent = new Intent(view.getContext(), DoaBangunt.class);
view.getContext().startActivity(myIntent);
}
else if ( 2 == getAdapterPosition() )
{
Intent myIntent = new Intent(view.getContext(), DoaJimak.class);
view.getContext().startActivity(myIntent);
}
}
});
//Get radio button value
LayoutInflater inflater = (LayoutInflater) view.getContext().getSystemService(Context.LAYOUT_INFLATER_SERVICE);
View cV = inflater.inflate(R.layout.activity_settings, null,false);
RadioGroup radioGroup = (RadioGroup)cV.findViewById(R.id.radioSex);
SharedPreferences sharedPreferences = view.getContext().getSharedPreferences("MY_SHARED_PREF", Activity.MODE_PRIVATE);
int savedRadioIndex = sharedPreferences.getInt(KEY_SAVED_RADIO_BUTTON_INDEX, 0);
RadioButton savedCheckedRadioButton = (RadioButton)radioGroup.getChildAt(savedRadioIndex);
savedCheckedRadioButton.setChecked(true);
RadioGroup genderGroup = (RadioGroup) cV.findViewById(R.id.radioSex);
RadioButton male = (RadioButton) cV.findViewById(R.id.theme1);
RadioButton female = (RadioButton) cV.findViewById(R.id.theme2);
if (genderGroup.getCheckedRadioButtonId() == -1) {
nomor.setBackgroundColor(view.getResources().getColor(R.color.colorPrimaryDark));
} else {
if (male.isChecked()) { // one of the radio buttons is checked
nomor.setBackgroundDrawable(ContextCompat.getDrawable(view.getContext(), R.drawable.rounded_drawable));
}
else if (female.isChecked()) {
nomor.setBackgroundDrawable(ContextCompat.getDrawable(view.getContext(), R.drawable.rounded_drawable_red));
}
}
} //TidurViewHolder(View view)
public void setViewData(final Story story, final int adapterPosition) {
if (story.getIsLiked() == 1) {
likeCheckBox.setChecked(true);
}
else {
likeCheckBox.setChecked(false);
}
likeCheckBox.setOnCheckedChangeListener(new CompoundButton.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
changedItemPosition = adapterPosition;
if (buttonView.isPressed()) {
if (isChecked) {
isLiked = true;
updateLikes();
appPreferences.saveFavouriteCard(story);
Toast.makeText(context, "Saved", Toast.LENGTH_SHORT).show();
}
else {
isLiked = false;
updateLikes();
appPreferences.deleteCard(story.getIdStory());
Toast.makeText(context, "Removed", Toast.LENGTH_SHORT).show();
}
}
}
});
} //setviewdata
public void updateLikes() {
if (isLiked && storyList.get(changedItemPosition).getIsLiked() == 0) { //jika dilakukan like (pada posisi hati kosong) di halaman home
storyList.get(changedItemPosition).setIsLiked(1); //maka jadikan hati berwarna merah di halaman favourite list
notifyItemChanged(changedItemPosition, ACTION_LIKE_IMAGE_CLICKED);
}
else if (!isLiked && storyList.get(changedItemPosition).getIsLiked() == 1) { //jika like dicabut (pada posisi hati yang sedang merah) di halaman home
storyList.get(changedItemPosition).setIsLiked(0); //maka cabut juga warna merah di halaman favourite list
notifyItemChanged(changedItemPosition, ACTION_LIKE_IMAGE_CLICKED);
}
} //updateLikes
}//Class TidurViewHolder
}
The error result is, it is showing null... Which mean no ID that can be obtained.

In your for loop you are not setting id of your List, but your new Story.
Instead of:
for (int i=0; i<storyList.size(); i++) {
Story story = new Story();
story.setIdStory(String.valueOf(i));
}
Use this:
for (int i=0; i<storyList.size(); i++) {
storyList.get(i).setIdStory(String.valueOf(i));
}
Also because your index i=0 starts from zero, you should change for loop index i to start from 1 like this:
for (int i=1; i<=storyList.size(); i++) {
storyList.get(i).setIdStory(String.valueOf(i));
}
Check this main activity:
public class MainActivity extends AppCompatActivity {
private static final String TAG = MainActivity.class.getSimpleName();
// CONNECTION_TIMEOUT and READ_TIMEOUT are in milliseconds
private ArrayList<Story> storyList;
// url to fetch contacts json
private static final String URL = "https://api.kafeinkode.com/childtidur.json";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
storyList = new ArrayList<>();
//Fetch JSON data
fetchData();
}
private void fetchData(){
JsonArrayRequest request = new JsonArrayRequest(URL, new Response.Listener<JSONArray>() {
#Override
public void onResponse(JSONArray response) {
Log.d(TAG, response.toString());
if (response.length() > 0) {
// Parsing json
List<Story> items = new Gson().fromJson(response.toString(), new TypeToken<List<Story>>() {}.getType());
// adding contacts to contacts list
storyList.clear();
storyList.addAll(items);
for (int i=0; i<storyList.size(); i++) {
storyList.get(i).setIdStory(String.valueOf(i + 1));
}
Log.d("StoryLid: ", storyList.toString());
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
// error in getting json
Log.e(TAG, "Error: " + error.getMessage());
}
});
VolleyService.getInstance(this).getRequestQueue().add(request);
}
}
As a result you have response:

ListView doesn't refresh with notifydatasetchanged

I have a MySQL database of two columns displayed in an android ListView. I use Retrofit 1.9 to get the data from MySQL. The adapter for the ListView is a BaseAdapter and I don't have a DatabaseHelperclass. When I add a data in the ListView from my mobile phone, it doesn't refresh the ListView. I have to close and restart the app. I try to refresh with listViewAdapter.notifyDataSetChanged();.
This is the fragment where the listview is:
public class rightFragment extends Fragment {
String BASE_URL = "http://awebsite.com";
View view;
ListView listView;
ListViewAdapter listViewAdapter;
Button buttondisplay;
Button buttonadd;
EditText new_id;
EditText newWordFra;
EditText newWordDeu;
ArrayList<String> id = new ArrayList<>();
ArrayList<String> fra = new ArrayList<>();
ArrayList<String> deu = new ArrayList<>();
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
view = inflater.inflate(com.example.geeko.Deu.R.layout.fragment_right, container, false);
listView = (ListView) view.findViewById(com.example.geeko.Deu.R.id.listView); //<<<< ADDED NOTE use your id
listViewAdapter = new ListViewAdapter(getActivity(), id, fra, deu);
displayData();
buttondisplay = (Button) view.findViewById(com.example.geeko.Deu.R.id.buttondisplay);
buttonadd = (Button) view.findViewById(com.example.geeko.Deu.R.id.buttonadd);
buttondelete = (Button) view.findViewById(com.example.geeko.Deu.R.id.newID);
newWordFra = (EditText) view.findViewById(com.example.geeko.Deu.R.id.newWordFra);
newWordDeu = (EditText) view.findViewById(com.example.geeko.Deu.R.id.newWordDeu);
buttonadd.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
//Toast.makeText(MainActivity.this , "button add", Toast.LENGTH_LONG).show();
insert_data();
listViewAdapter.notifyDataSetChanged();
}
});
buttondisplay.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
if (buttondisplay.getText().toString().contains("Show")) {
listView.setAdapter(listViewAdapter);
buttondisplay.setText("Hide");
} else {
listView.setAdapter(null);
buttondisplay.setText("Show");
}
}
});
listView.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long ids) {
new_id.setText(id.get(position));
newWordFra.setText(fra.get(position));
newWordDeu.setText(deu.get(position));
}
});
return view;
}
public void insert_data() {
RestAdapter adapter = new RestAdapter.Builder()
.setEndpoint(BASE_URL) //Setting the Root URL
.build();
AppConfig.insert api = adapter.create(AppConfig.insert.class);
api.insertData(
newWordFra.getText().toString(),
newWordDeu.getText().toString(),
new Callback<Response>() {
#Override
public void success(Response result, Response response) {
try {
BufferedReader reader = new BufferedReader(new InputStreamReader(result.getBody().in()));
String resp;
resp = reader.readLine();
Log.d("success", "" + resp);
JSONObject jObj = new JSONObject(resp);
int success = jObj.getInt("success");
if(success == 1){
Toast.makeText(getActivity(), "Successfully inserted", Toast.LENGTH_SHORT).show();
} else{
Toast.makeText(getActivity(), "Insertion Failed", Toast.LENGTH_SHORT).show();
}
} catch (IOException e) {
Log.d("Exception", e.toString());
} catch (JSONException e) {
Log.d("JsonException", e.toString());
}
}
#Override
public void failure(RetrofitError error) {
Toast.makeText(getActivity(), error.toString(), Toast.LENGTH_LONG).show();
}
}
);
}
public void displayData() {
RestAdapter adapter = new RestAdapter.Builder()
.setEndpoint(BASE_URL) //Setting the Root URL
.build();
AppConfig.read api = adapter.create(AppConfig.read.class);
api.readData(new Callback<JsonElement>() {
#Override
public void success(JsonElement result, Response response) {
String myResponse = result.toString();
Log.d("response", "" + myResponse);
try {
JSONObject jObj = new JSONObject(myResponse);
int success = jObj.getInt("success");
if (success == 1) {
JSONArray jsonArray = jObj.getJSONArray("details");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject jo = jsonArray.getJSONObject(i);
id.add(jo.getString("id"));
fra.add(jo.getString("fra"));
deu.add(jo.getString("deu"));
}
listView.setAdapter(listViewAdapter);
} else {
Toast.makeText(getActivity(), "No Details Found", Toast.LENGTH_SHORT).show();
}
} catch (JSONException e) {
Log.d("exception", e.toString());
}
}
#Override
public void failure(RetrofitError error) {
Log.d("Failure", error.toString());
Toast.makeText(getActivity(), error.toString(), Toast.LENGTH_LONG).show();
}
}
);
}
}
This is the listViewAdpater class :
public class ListViewAdapter extends BaseAdapter {
private final Context context;
private ArrayList<String> id = new ArrayList<String>();
private ArrayList<String> fra = new ArrayList<String>();
private ArrayList<String> deu = new ArrayList<String>();
LayoutInflater layoutInflater;
public ListViewAdapter(Context ctx, ArrayList<String> id, ArrayList<String> fra, ArrayList<String> deu) {
this.context = ctx;
this.id = id;
this.fra = fra;
this.deu = deu;
}
#Override
public int getCount() {
return id.size();
}
#Override
public Object getItem(int position) {
return id.get(position);
}
#Override
public long getItemId(int position) {
return position;
}
#SuppressLint("ViewHolder")
#Override
public View getView(final int position, View view, ViewGroup parent) {
final Holder holder;
if (view == null) {
layoutInflater = (LayoutInflater) context.getSystemService
(Context.LAYOUT_INFLATER_SERVICE);
view = layoutInflater.inflate(R.layout.list_item, null);
holder = new Holder();
holder.txt_fra = (TextView) view.findViewById(R.id.fra);
holder.txt_deu = (TextView) view.findViewById(R.id.deu);
view.setTag(holder);
} else {
holder = (Holder) view.getTag();
}
holder.txt_fra.setText(fra.get(position));
holder.txt_deu.setText(deu.get(position));
return view;
}
static class Holder {
TextView txt_fra, txt_deu;
}
}
Should I create a method to refresh my ListView?

First of all I would suggest to remove the unnecessary initialization of your variables inside the Adapter:
private ArrayList<String> id = new ArrayList<String>();
private ArrayList<String> fra = new ArrayList<String>();
private ArrayList<String> deu = new ArrayList<String>();
By assigning the pointer from your fragment you will already assign an initialized ArrayList. You want both pointers to point at the same ArrayList Object so changes apply to both.
Apparently, the data stored in the Adapter is not being updated correctly. I would suggest to debug your app - setting the breakpoint so that you can see the data that the Adapter stores after an update.
The idea of writing a method for updates has already been implemented with the notifyDataSetChanged(). Just override the method in your adapter and do eventual changes before calling the super.notifyDataSetChanged().
If you have any success with those changes let us know.

buttonadd.setOnClickListener(new View.OnClickListener() {
...
insert_data();
listViewAdapter.notifyDataSetChanged();
}
});
In your onClickListener, you are calling insert_data(), followed by listViewAdapter.notifyDataSetChanged()
insert_data() method is sending a network request to retrieve the data to populate the list. BUT, you are calling notifyDataSetChanged BEFORE the network request is done. That's why the listView is empty, and will stay empty. You need to wait AFTER the network request and AFTER you have populated your ArrayList with the data to call notifyDataSetChanged.
How do we know the network request is done? Simply at the end of the callback (which you've implemented):
new Callback<Response>() {
#Override
public void success(Response result, Response response) {...
At the end of the success method, you call listViewAdapter.notifyDataSetChanged() method.
Hope that makes sense! Try it and let us know what happens

I've founded a solution. I've added getActivity.recreate(); in the method insert_data.
public void success(Response result, Response response) {
try {
BufferedReader reader = new BufferedReader
(new InputStreamReader(result.getBody().in()));
String resp;
resp = reader.readLine();
Log.d("success", "" + resp);
JSONObject jObj = new JSONObject(resp);
int success = jObj.getInt("success");
if(success == 1){
Toast.makeText(getActivity(), "Successfully inserted",
Toast.LENGTH_SHORT).show();
getActivity().recreate();
} else{
Toast.makeText(getActivity(), "Insertion Failed",
Toast.LENGTH_SHORT).show();
}
} catch (IOException e) {
Log.d("Exception", e.toString());
} catch (JSONException e) {
Log.d("JsonException", e.toString());
}
}
I'm not sure that is the best solution but it works.

RecyclerView not showing JSON sent from localhost just blank screen

Hi guys I dont have much experience with AsyncTask and this is my first time using RecyclerView besides a couple of tutorials I done to learn about it.
If I use dummy data in EventActivity everything works fine and a list shown on the screen. But when I create an ArrayList of EventItems and pass that to the adapter it's just a blank screen. The JSON from localhost is being parsed and sent to the EventItem class. I have tried several things to get it to work but as my experience with AsyncTask and RecyclerView are limited I end up just crashing the app and getting a null pointer exception.
I think that the RecyclerView is being created before the JSON has been retrieved from localhost and this is what's causing the blank screen or null pointer exception but I'm not 100% sure and dont know how to fix the issue if I am correct.
Any help is appreciated.
EventActivity
public class EventActivity extends AppCompatActivity {
private RecyclerView mRecyclerView;
private RecyclerView.Adapter mAdapter;
private RecyclerView.LayoutManager mLayoutManager;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_event);
fetchEvents();//call EventBackgroundWorker
//ArrayList<EventItem> eventList = new EventItem().getRecyclerList();//causes java null pointer exception
ArrayList<EventItem> eventList = new ArrayList<>();
//Dummie data
// eventList.add(new EventItem (1, "Title1", "Date", "endDate", "Location1", 5, 1111));
// eventList.add(new EventItem (R.drawable.ic_favourite, "Title2", "11/07/2018", "11/07/2018", "Wales", 10, 5));
// eventList.add(new EventItem (R.drawable.ramspeed_custom, "Title3", "11/01/2018", "11/09/2018", "Paris, France", 0, 90));
// eventList.add(new EventItem (R.drawable.ramspeed_custom, "Title4", "12/01/2018", "11/09/2018", "New York", 20, 500));
// eventList.add(new EventItem (R.drawable.ic_favourite, "Title5", "Mon 11/05/2015", "11/09/2018", "London, England", 5, 500));
// eventList.add(new EventItem (R.drawable.biker, "Title6", "Mon 11/05/2018", "20/07/2018", "Swords Dublin", 0, 500));
mRecyclerView = (RecyclerView) findViewById(R.id.event_recycler_view);
mRecyclerView.setHasFixedSize(true);//increase performance of app if recyclerView does not increase in size
mLayoutManager = new LinearLayoutManager(this);
// mAdapter = new EventAdapter(eventList);
mAdapter = new EventAdapter(eventList);//context added for testing //////////////////////////////
// mAdapter = new EventAdapter(new ArrayList<EventItem>(0));
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
// buildRecyclerView();
}
//run background thread
private void fetchEvents(){
// String username = "user";
// String userPassword = "password";
String startConnectionCondition = "event";
//this passes the context
EventBackgroundWorker backgroundWorker = new EventBackgroundWorker(this);
backgroundWorker.execute(startConnectionCondition, null);
}
/* private void buildRecyclerView(){
ArrayList<EventItem> eventList = new EventItem().getRecyclerList();
mRecyclerView = (RecyclerView) findViewById(R.id.event_recycler_view);
mRecyclerView.setHasFixedSize(true);//increase performance of app if recyclerView does not increase in size
mLayoutManager = new LinearLayoutManager(this);
// mAdapter = new EventAdapter(eventList);
mAdapter = new EventAdapter(eventList);//context added for testing
// mAdapter = new EventAdapter(new ArrayList<EventItem>(0));
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
}
*/
/* public void showEventList(boolean b){
ArrayList<EventItem> eventList = new ArrayList<>();
for(int i =0; i< eventList.size(); i++){
eventList.get(i);
Log.d("tag","eventList from main " + eventList);
}
mAdapter = new EventAdapter(eventList);
mRecyclerView.setLayoutManager(mLayoutManager);
mRecyclerView.setAdapter(mAdapter);
}*/
}//MainActivity
EventAdapter
public class EventAdapter extends RecyclerView.Adapter<EventAdapter.EventViewHolder> {
private ArrayList<EventItem> mEventList;
Context context;
//constructor for EventAdapter
public EventAdapter(ArrayList<EventItem> eventList){
// context =c;
mEventList = eventList;
Log.d("tag","EventAdapter eventlist variable called from constructor " + eventList);
}
public static class EventViewHolder extends RecyclerView.ViewHolder{
public ImageView mPromoImage;
public TextView mTitle;
public TextView mStartDate;
public TextView mEndDate;
public TextView mLocation;
public TextView mFee;
public ImageView mFavourite;
//constructor for EventViewHolder class
public EventViewHolder(View itemView) {
super(itemView);
// mPromoImage = (ImageView) itemView.findViewById(R.id.event_promotional_image);
mTitle = (TextView) itemView.findViewById(R.id.event_title_textView);
mStartDate = (TextView) itemView.findViewById(R.id.event_start_textView);
mEndDate = (TextView) itemView.findViewById(R.id.event_end_textView);
mLocation = (TextView) itemView.findViewById(R.id.event_location_textView);
mFee = (TextView) itemView.findViewById(R.id.event_fee_textView);
// mFavourite = (ImageView) itemView.findViewById(R.id.event_favourite_image);
Log.d("tag", "EventViewHolder being called");
}
}//EventViewHolder class
#Override
public EventViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.item_event, parent, false);
//create view holder
EventViewHolder viewHolder = new EventViewHolder(v);
return viewHolder;
}
//pass values to inflated XML Views in item_event.xml
#Override
public void onBindViewHolder(EventViewHolder holder, int position) {
EventItem currentEvent = mEventList.get(position);
// holder.mPromoImage.setImageResource(currentEvent.getEventPromoImage());
holder.mTitle.setText(currentEvent.getEventTitle());
holder.mStartDate.setText(currentEvent.getEventStartDate());
holder.mEndDate.setText(currentEvent.getEventEndDate());
holder.mLocation.setText(currentEvent.getEventLocation());
holder.mFee.setText(String.valueOf(currentEvent.getEventFee()));//int value passed
// holder.mFavourite.setImageResource(currentEvent.getEventFavourite());
//Log.d("tag", "position" + position );
Log.d("tag","eventAdapter " + currentEvent.getEventTitle());
}
//how many items there will be
#Override
public int getItemCount() {
return mEventList.size();
}
}
EventItem
public class EventItem {
private int mEventPromoImage;
private int mId;
private String mEventTitle;
private String mEventStartDate;
private String mEventEndDate;
private String mEventLocation;
private int mEventFee;
private int mEventViews;
// public EventItem(){}
public EventItem(int id, String eventTitle, String eventStartDate,
String eventEndDate, String eventLocation, int eventFee, int eventViews){
// mEventPromoImage = eventPromoImage;
mId = id;
mEventTitle = eventTitle;
mEventStartDate = eventStartDate;
mEventEndDate = eventEndDate;
mEventLocation = eventLocation;
mEventFee = eventFee;
mEventViews = eventViews;
Log.d("tag","EVENTITEM title EventItem" + mEventTitle);
// Log.d("tag","EVENTITEM startDate EventItem" + mEventStartDate );
// Log.d("tag","EVENTITEM endDate EventItem" + mEventEndDate );
// Log.d("tag","EVENTITEM address EventItem" + mEventLocation);
// Log.d("tag","EVENTITEM fee EventItem" + mEventFee);
}
public int getEventPromoImage() {
return mEventPromoImage;
}
public void setEventPromoImage(int mEventPromoImage) {
this.mEventPromoImage = mEventPromoImage;
}
public int getEventId() {
return mId;
}
public void setEventId(int mId){
this.mId = mId;
}
public String getEventTitle() {
Log.d("tag","getEventTitle() " + mEventTitle);
return mEventTitle;
}
public void setEventTitle(String mEventTitle) {
this.mEventTitle = mEventTitle;
}
public String getEventStartDate() {
return mEventStartDate;
}
public void setEventStartDate(String mEventStartDate) {
this.mEventStartDate = mEventStartDate;
}
public String getEventEndDate(){
return mEventEndDate;
}
public void setEventEndDate(String mEventEndDate){
this.mEventEndDate = mEventEndDate;
}
public String getEventLocation() {
return mEventLocation;
}
public void setEventLocation(String mEventLocation) {
this.mEventLocation = mEventLocation;
}
public int getEventFee() {
return mEventFee;
}
public void setEventFee(int mEventFee) {
this.mEventFee = mEventFee;
}
public int getEventViews(){
return mEventViews;
}
public void getEventViews(int mEventViews) {
this.mEventViews = mEventViews;
}
public ArrayList<EventItem> getRecyclerList(){
ArrayList event = new ArrayList();
event.add(mEventTitle);
event.add(mEventStartDate);
event.add(mEventEndDate);
event.add(mEventLocation);
event.add(mEventFee);
event.add(mEventViews);
return event;
}
}
EventBackgroundWorker
public class EventBackgroundWorker extends AsyncTask<String, Void, String> {
Context context;
AlertDialog alert;
public static final String REQUEST_URL = "http://10.0.2.2/m/event/";
public EventBackgroundWorker(Context ctxt) {
context = ctxt;
}
//Invoked on UI thread before doInBackground is called
#Override
protected void onPreExecute() {
alert = new AlertDialog.Builder(context).create();
alert.setTitle("Result from server");
}
#Override
protected String doInBackground(String... params) {
String type = params[0];//eventList
//String login_url = "http://10.0.2.2/m/event/";
if(type.equals("event")){
try {
String user_name = params[1];
URL url = new URL(REQUEST_URL);
HttpURLConnection httpURLConnection = (HttpURLConnection) url.openConnection();
httpURLConnection.setRequestMethod("POST");
httpURLConnection.setDoOutput(true);
httpURLConnection.setDoInput(true);
httpURLConnection.connect();//works without this connect Find out why
OutputStream outputStream = httpURLConnection.getOutputStream();
BufferedWriter bufferedWriter = new BufferedWriter(new OutputStreamWriter(outputStream, "UTF-8"));
String post_data = URLEncoder.encode("getEvents", "UTF-8");
bufferedWriter.write(post_data);
bufferedWriter.flush();
bufferedWriter.close();
outputStream.close();
//read response
InputStream inputStream = httpURLConnection.getInputStream();
BufferedReader bufferedReader = new BufferedReader(new InputStreamReader(inputStream, "iso-8859-1"));
String result = "";
String line;
while((line = bufferedReader.readLine()) != null){
result += line;
}
//parse JSON event Array
// Create an empty ArrayList that we can start adding events to
ArrayList<EventItem> eventArray = new ArrayList<>();
JSONArray baseJsonResponse = new JSONArray(result);
for(int i =0; i < baseJsonResponse.length(); i++){
JSONObject event = baseJsonResponse.getJSONObject(i);
int id = event.getInt("id");
String title = event.getString("title");
String address = event.getString("address");
String startDate = event.getString("startDate");
String endDate = event.getString("endDate");
int fee = event.getInt("fee");
int views = event.getInt("views");
//Send data to eventItem Object
EventItem eventObject = new EventItem(id,title,address,startDate,endDate,fee,views);
eventArray.add(eventObject);
/* Log.d("tag", "JSON id " + id);
Log.d("tag", "JSON title " + title);
Log.d("tag", "JSON address " + address);
Log.d("tag", "JSON startDate " + startDate);
Log.d("tag", "JSON endDate " + endDate);
Log.d("tag", "JSON fee " + fee);
Log.d("tag", "JSON views " + views);*/
}
bufferedReader.close();
inputStream.close();
httpURLConnection.disconnect();
return result;
} catch (MalformedURLException e) {//added for URL object
e.printStackTrace();
} catch (IOException e) {
//HTPURLConnection
} catch (JSONException e) {
e.printStackTrace();
}
}
return null;
}
#Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
//results from doInBackground are passed here
#Override
protected void onPostExecute(String result) {
Log.d("tag", "onPostExecute called" + result);
alert.setMessage(result);
alert.show();
}
}

The AsyncTask creates eventArray but does nothing with it. doInBackground() should return the eventArray and onPostExecute() should set it as adapter content (by a Callback or by setting the Adapter instance at the AsyncTask object). Your Adapter should have a setter for the content which should call notifyDataSetChanged().

Return button to previous activity with BaseAdapter

I currently have two activities doing HTTP requests.
The first activity contains a CustomList class extends BaseAdapter.
On the second, there is a previous button allowing me to return to the first activity.
Returning to the first activity, I would like to be able to recover the state in which I left it. That is to say to be able to find the information which also come from an HTTP request. I would like to find the data "infos_user" which is in the first activity and all the data in the BaseAdapter.
My architecture is as follows: Activity 0 (HTTP request) -> Activity 1 (with BaseAdapter and HTTP request) -> Activity 2 (HTTP request)
I put all the code because I really don't know how can I do this :/
First activity:
public class GetChildrenList extends AppCompatActivity implements View.OnClickListener {
private ArrayList<Child> childrenImeList = new ArrayList<Child>();
private Button btn_previous;
private ListView itemsListView;
private TextView tv_signin_success;
int id = 0;
String infos_user;
String email;
String password;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.get_children_list);
infos_user = (String) getIntent().getSerializableExtra("infos_user");
Intent intent = new Intent(GetChildrenList.this , GetLearningGoalsList.class);
intent.putExtra("username", infos_user);
btn_previous = (Button) findViewById(R.id.btn_previous);
btn_previous.setOnClickListener(this);
tv_signin_success = (TextView) findViewById(R.id.tv_signin_success);
tv_signin_success.setText("Bonjour " + infos_user + "!");
itemsListView = (ListView)findViewById(R.id.list_view_children);
new GetChildrenAsync().execute();
}
class GetChildrenAsync extends AsyncTask<String, Void, ArrayList<Child>> {
private Dialog loadingDialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
loadingDialog = ProgressDialog.show(GetChildrenList.this, "Please wait", "Loading...");
}
#Override
protected ArrayList<Child> doInBackground(String... params) {
int age = 0;
email = (String) getIntent().getSerializableExtra("email");
password = (String) getIntent().getSerializableExtra("password");
String first_name = null;
String last_name = null;
try {
SendRequest sr = new SendRequest();
String result = sr.sendHttpRequest("http://" + sr.getIP_ADDRESS() + "/childrenime/list", "GET", true, email, password);
String jsonResult = "{ \"children\":" + result + "}";
Log.d("result1", jsonResult);
//Manage JSON result
JSONObject jsonObject = new JSONObject(jsonResult);
JSONArray childrenArray = jsonObject.getJSONArray("children");
for (int i = 0; i < childrenArray.length(); ++i) {
JSONObject child = childrenArray.getJSONObject(i);
id = child.getInt("id");
first_name = child.getString("first_name");
last_name = child.getString("last_name");
age = child.getInt("age");
String name = first_name + " " + last_name;
childrenImeList.add(new Child(id,name,age));
}
} catch (JSONException e) {
e.printStackTrace();
}
return childrenImeList;
}
#Override
protected void onPostExecute(final ArrayList<Child> childrenListInformation) {
loadingDialog.dismiss();
if(childrenListInformation.size() > 0) {
CustomListChildrenAdapter adapter = new CustomListChildrenAdapter(GetChildrenList.this, childrenListInformation);
itemsListView.setAdapter(adapter);
}
else{
Toast.makeText(getApplicationContext(), "Impossible de récupérer la liste des enfants", Toast.LENGTH_LONG).show();
}
}
}
}
BaseAdapter:
public class CustomListChildrenAdapter extends BaseAdapter implements View.OnClickListener {
private Context context;
private ArrayList<Child> children;
private Button btnChoose;
private TextView childrenName;
private TextView childrenAge;
public CustomListChildrenAdapter(Context context, ArrayList<Child> children) {
this.context = context;
this.children = children;
}
#Override
public int getCount() {
return children.size(); //returns total item in the list
}
#Override
public Object getItem(int position) {
return children.get(position); //returns the item at the specified position
}
#Override
public long getItemId(int position) {
return position;
}
#Override
public View getView(final int position, View convertView, ViewGroup parent) {
View view;
if (convertView == null) {
LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
view = inflater.inflate(R.layout.layout_list_view_children,null);
childrenName = (TextView)view.findViewById(R.id.tv_childrenName);
childrenAge = (TextView) view.findViewById(R.id.tv_childrenAge);
btnChoose = (Button) view.findViewById(R.id.btn_choose);
btnChoose.setOnClickListener(this);
} else {
view = convertView;
}
btnChoose.setTag(position);
Child currentItem = (Child) getItem(position);
childrenName.setText(currentItem.getChildName());
childrenAge.setText(currentItem.getChildAge() + "");
return view;
}
#Override
public void onClick(View v) {
Integer position = (Integer) v.getTag();
Child item = (Child) getItem(position);
String email = (String) ((Activity) context).getIntent().getSerializableExtra("email");
String password = (String) ((Activity) context).getIntent().getSerializableExtra("password");
Intent intent = new Intent(context, GetLearningGoalsList.class);
intent.putExtra("idChild",item.getId());
intent.putExtra("email",email);
intent.putExtra("password",password);
context.startActivity(intent);
}
}
Second Activity:
public class GetLearningGoalsList extends AppCompatActivity implements View.OnClickListener {
private ArrayList<LearningGoal> childrenLearningList = new ArrayList<LearningGoal>();
private Button btn_previous;
private ListView itemsListView;
String email;
String password;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.get_learning_goals_list);
btn_previous = (Button) findViewById(R.id.btn_previous);
btn_previous.setOnClickListener(this);
itemsListView = (ListView)findViewById(R.id.list_view_learning_goals);
new GetLearningGoalsAsync().execute();
}
#Override
public void onClick(View v) {
Intent myIntent = new Intent(GetLearningGoalsList.this, GetChildrenList.class);
myIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(myIntent);
return;
}
class GetLearningGoalsAsync extends AsyncTask<String, Void, ArrayList<LearningGoal>> {
private Dialog loadingDialog;
#Override
protected void onPreExecute() {
super.onPreExecute();
loadingDialog = ProgressDialog.show(GetLearningGoalsList.this, "Please wait", "Loading...");
}
#Override
protected ArrayList<LearningGoal> doInBackground(String... params) {
int id = 0;
email = (String) getIntent().getSerializableExtra("email");
password = (String) getIntent().getSerializableExtra("password");
int idChild = (int) getIntent().getSerializableExtra("idChild");
String name = null;
String start_date = null;
String end_date = null;
try {
List<BasicNameValuePair> parameters = new LinkedList<BasicNameValuePair>();
parameters.add(new BasicNameValuePair("idchild", Integer.toString(idChild)));
SendRequest sr = new SendRequest();
String result = sr.sendHttpRequest("http://" + sr.getIP_ADDRESS() + "/learningchild/list"+ "?"+ URLEncodedUtils.format(parameters, "utf-8"), "POST", true, email, password);
String jsonResult = "{ \"learningGoals\":" + result + "}";
Log.d("result1", jsonResult);
//Manage JSON result
JSONObject jsonObject = new JSONObject(jsonResult);
JSONArray learningGoalsArray = jsonObject.getJSONArray("learningGoals");
for (int i = 0; i < learningGoalsArray.length(); ++i) {
JSONObject learningGoal = learningGoalsArray.getJSONObject(i);
id = learningGoal.getInt("id");
name = learningGoal.getString("name");
start_date = learningGoal.getString("start_date");
end_date = learningGoal.getString("end_date");
childrenLearningList.add(new LearningGoal(id,name,start_date,end_date));
}
} catch (JSONException e) {
e.printStackTrace();
}
return childrenLearningList;
}
#Override
protected void onPostExecute(final ArrayList<LearningGoal> learningListInformation) {
loadingDialog.dismiss();
if(learningListInformation.size() > 0) {
CustomListLearningGoalAdapter adapter = new CustomListLearningGoalAdapter(GetLearningGoalsList.this, learningListInformation);
itemsListView.setAdapter(adapter);
}
else{
Toast.makeText(getApplicationContext(), "Impossible de récupérer la liste des scénarios de cet enfant", Toast.LENGTH_LONG).show();
}
}
}
}
Thanks for your help.

if you want to maintain GetChildrenList state as it is then just call finish() rather than new intent on previous button click as follow
replace in GetLearningGoalsList
#Override
public void onClick(View v) {
Intent myIntent = new Intent(GetLearningGoalsList.this, GetChildrenList.class);
myIntent.setFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
startActivity(myIntent);
return;
}
with
#Override
public void onClick(View v) {
finish();
}

ExpandableListView with multiple choice save selected item into an array

I have an array that is filled with API data, and I have an expandablelistview to show the items of that array, now what I'm trying to do is when the user clicks on an item it saves th ID of that item into an array, so if the user select 2 items I want 2 Ids in my array, what is happening now is this: no matter if I select only one of the items it gets all of them and save it inside my array.
public class MainActivity extends Fragment {
private ExpandListAdapter ExpAdapter;
private ExpandableListView ExpandList;
private Button notificar;
private Context context;
MainActivity mContext;
private Button footer;
private double RaioEscola;
private CircleOptions mCircle;
GPSTracker tracker;
private Location location;
private Integer IdEscola;
public MainActivity() {
}
public MainActivity(Context context) {
this.context = context;
}
#Override
public View onCreateView(final LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
final View rootView = inflater.inflate(R.layout.expand, container, false);
ExpandList = (ExpandableListView) rootView.findViewById(R.id.exp_list);
notificar = (Button) rootView.findViewById(R.id.btnGetMoreResults);
new asyncTask(MainActivity.this).execute();
return rootView;
}
private class asyncTask extends AsyncTask<String, Void, Void> {
private ProgressDialog pd;
public asyncTask(MainActivity context) {
mContext = context;
pd = new ProgressDialog(getActivity());
pd.setTitle("Por Favor Espere ...");
pd.setMessage("Enviando ...");
if (!pd.isShowing()) {
pd.show();
}
}
#Override
protected Void doInBackground(final String... params) {
try {
String[] resposta = new WebService().get("filhos");
if (resposta[0].equals("200")) {
JSONObject mJSONObject = new JSONObject(resposta[1]);
JSONArray dados = mJSONObject.getJSONArray("data");
/* cria o array que vai receber os dados da api */
final ArrayList<Escolas> mArrayList = new ArrayList<Escolas>();
/* percorre o array, adicionando cada linha encontrada em um ArrayList */
for (int i = 0; i < dados.length(); i++) {
JSONObject item = dados.getJSONObject(i);
Escolas mEscolas = new Escolas();
mEscolas.setId_escola(item.optInt("id_escola"));
mEscolas.setCnpj(item.getString("cnpj"));
mEscolas.setRazao_social(item.getString("razao_social"));
mEscolas.setNome_fantasia(item.getString("nome_fantasia"));
mEscolas.setDistancia(Float.valueOf(item.getString("distancia")));
mEscolas.setLogradouro(item.optString("logradouro"));
mEscolas.setNumero(item.optString("numero"));
mEscolas.setBairro(item.getString("bairro"));
mEscolas.setComplemento(item.getString("complemento"));
mEscolas.setCep(item.getString("cep"));
mEscolas.setCidade(item.getString("cidade"));
mEscolas.setEstado(item.getString("estado"));
mEscolas.setLatitude(Float.parseFloat(item.getString("latitude")));
mEscolas.setLongitude(Float.parseFloat(item.getString("longitude")));
RaioEscola = Double.parseDouble(String.valueOf(mEscolas.getDistancia()));
IdEscola = mEscolas.getId_escola();
JSONObject alunos = item.optJSONObject("alunos");
JSONArray data = alunos.getJSONArray("data");
if (data != null) {
ArrayList<Filhos> arrayalunos = new ArrayList<Filhos>();
for (int a = 0; a < data.length(); a++) {
Filhos mFilhos = new Filhos();
JSONObject clientes = data.getJSONObject(a);
mFilhos.setId_aluno(clientes.optInt("id_aluno"));
mFilhos.setNome(clientes.optString("nome"));
mFilhos.setSobrenome(clientes.optString("sobrenome"));
mFilhos.setFoto(clientes.optString("foto"));
mFilhos.setModalidade_de_ensino(clientes.optString("modalidade_de_ensino"));
mFilhos.setObservacoes(clientes.optString("observacoes"));
arrayalunos.add(mFilhos);
}
mEscolas.setalunos(arrayalunos);
}
/* popula o array de viagens */
mArrayList.add(mEscolas);
ExpAdapter = new ExpandListAdapter(getActivity(), mArrayList);
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
ExpandList.setAdapter(ExpAdapter);
ExpAdapter.notifyDataSetChanged();
ExpAdapter.setChoiceMode(ExpandListAdapter.CHOICE_MODE_MULTIPLE);
ExpandList.setOnChildClickListener(new ExpandableListView.OnChildClickListener() {
#Override
public boolean onChildClick(final ExpandableListView parent, View v, final int groupPosition, final int childPosition, final long id) {
ExpAdapter.setClicked(groupPosition, childPosition);
final int index = parent.getFlatListPosition(ExpandableListView.getPackedPositionForChild(groupPosition, childPosition));
parent.setItemChecked(index, true);
parent.setSelectedChild(groupPosition, childPosition, true);
parent.getChildAt(index);
notificar.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
class update extends TimerTask {
public void run() {
try {
getActivity().runOnUiThread(new Runnable() {
#Override
public void run() {
final float latitude = mArrayList.get(groupPosition).getLatitude();
final float longitude = mArrayList.get(groupPosition).getLongitude();
LatLng latLng = new LatLng(latitude, longitude);
drawMarkerWithCircle(latLng);
GPSTracker gps = new GPSTracker(getActivity());
double latitudegps = gps.getLatitude();
double longitudegps = gps.getLongitude();
float[] distance = new float[2];
Location.distanceBetween(mCircle.getCenter().latitude, mCircle.getCenter().longitude, latitudegps, longitudegps, distance);
if (distance[0] > mCircle.getRadius()) {
Toast.makeText(getActivity(), "Outside", Toast.LENGTH_LONG).show();
}
else {
Toast.makeText(getActivity(), "Inside", Toast.LENGTH_LONG).show();
AlertRest mAlertRest = new AlertRest();
try {
List<Integer> myIdList = new ArrayList<Integer>();
for (int i = 0; i < mArrayList.get(groupPosition).getalunos().size(); i++) {
Integer Idalunos = mArrayList.get(groupPosition).getalunos().get(i).getId_aluno();
myIdList.add(Idalunos);
}
mAlertRest.getNotificacao(1, mArrayList.get(groupPosition).getId_escola(), String.valueOf(myIdList), latitudegps, longitudegps);
}
catch (Exception e) {
e.printStackTrace();
}
}
}
});
}
catch (Exception e) {
e.printStackTrace();
}
}
}
Timer timer = new Timer();
timer.schedule(new update(), 0, 15000);
}
private void drawMarkerWithCircle(LatLng position) {
mCircle = new CircleOptions().center(position).radius(RaioEscola);
}
});
return false;
}
});
}
});
}
/* retorna um array de objetos */
}
else {
throw new Exception("[" + resposta[0] + "] ERRO: " + resposta[1]);
}
}
catch (Exception e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void cursor) {
if (pd.isShowing()) {
pd.dismiss();
}
}
}
}
AlertRest:
public class AlertRest extends WebService {
private String recurso = "notificacoes";
private String[] resposta;
private AlertModelo mAlertModelo;
public AlertModelo getNotificacao(Integer id_usuario, String token, Integer id_escola, String ids_aluno, Double latitude, Double longitude) throws Exception {
/* dispara a requisição para a API retornar os dados do "recurso" necessário */
resposta = new WebService().postToken(recurso, token, "{\"id_usuario\":" + id_usuario + "," + "\"id_escola\":" + id_escola + "," + "\"ids_aluno\":\"" + ids_aluno + "\"," + "\"latitude\":" + latitude + "," + "\"longitude\":" + longitude + "}");
JSONObject mJSONObject = new JSONObject(resposta[1]);
if (resposta[1].equals("201")) {
mAlertModelo = new AlertModelo();
mAlertModelo.setId_usuario(mJSONObject.getInt(String.valueOf(id_usuario)));
mAlertModelo.setId_escola(mJSONObject.getInt(String.valueOf(id_escola)));
mAlertModelo.setIds_aluno(mJSONObject.getInt(String.valueOf(ids_aluno)));
mAlertModelo.setLatitude(mJSONObject.getDouble(String.valueOf(latitude)));
mAlertModelo.setLongitude(mJSONObject.getDouble(String.valueOf(longitude)));
}
return mAlertModelo;
}
}

The code is difficult to follow due to few nested loops and running tasks.
Anyway, I suspect the code below is causing your app to save all (unselected) items in the list:
for (int i = 0; i < mArrayList.get(groupPosition).getalunos().size(); i++) {
Integer Idalunos = mArrayList.get(groupPosition).getalunos().get(i).getId_aluno();
myIdList.add(Idalunos);
}
Note: Iterating through the entire list is a suspect. It should pick a certain item or items in the list.
So...another set of relevant codes can help us determine the code fix. I am not certain if there is a bug here also.
parent.setItemChecked(index, true);
parent.setSelectedChild(groupPosition, childPosition, true);
parent.getChildAt(index);
Note: These codes may be fine. The key code, I think, is the index. I am not too familiar with ExpandableListView.
Finally, suggested code fix:
Integer Idalunos = mArrayList.get(groupPosition).getalunos().get(index).getId_aluno();
...
myIdList.add(Idalunos);
Notice the variable index is used to get the correct item, Idalunos.

You are using mArrayList variable for initializing adapter and for filling myIdList at the same time. Of course myIdList would contain full list of your adapter.
UPDATE
It would be better to define myIdList as field of your MainActivity class and initialize it in onCreateView method.
On click not just add the value - you should check if this value is allready in list:
if(myIdList.contains(Idalunos)) {
myIdList.remove(Idalunos);
} else {
myIdList.add(Idalunos);
}