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onItemSelected Listner are not trigger with the long String array from database

UPDATE:
I found the problem, the problem may cause by get the adapter content from SQL requset. Now I post my getLockerList() code here now.
I tested the function with long string
"asdajdnajkdaadasdaajd najkdaadasdaajdnajkdaadasdaajdnajkdaadasdaajdnaj kdaadasdaajdnajkdaadasdasdas"
and it still could work perfectly, so now I guess the problem is come from when I got the data.
I set a spinner with arrayadapter. The content of adapter is come from MySQL request.
I got the data and create the adapter successfully, but when I try to show what item was selected by user, it show nothing after I click the item.
I've tried add some system print to find out the problem, finally I found that the problem is the listener not even call, no matter onItemSelected or onNothingSelected
I think I may find the problem now, my view list is stored different location which is very long String. I tried change the content of the adapter to "test" and it work perfectly. So now the problem is now can I display the long string?
Here is my code:
public class PlaceOrderActivity extends AppCompatActivity implements AdapterView.OnItemSelectedListener {
private Spinner from_spinner;
private ArrayList<String> locker_list = new ArrayList<String>();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_place_order);
getLockerList();
from_spinner = (Spinner) findViewById(R.id.from_spinner);
from_spinner.setVisibility(View.VISIBLE);
ArrayAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_spinner_item,locker_list);
from_spinner.setAdapter(adapter);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
from_spinner.setOnItemSelectedListener(this);
}
private void getLockerList() {
// Response received from the server
Response.Listener<String> responseListener = new Response.Listener<String>() {
#Override
public void onResponse(String response) {
try {
JSONArray jsonResponse = new JSONArray(response);
//JSONObject jsonObject = jsonResponse.getJSONObject(0);
if (jsonResponse!=null) {
// System.out.println(jsonResponse);
for (int i=0;i< jsonResponse.length();i++)
{
JSONObject jsonObject = jsonResponse.getJSONObject(i);
String location = jsonObject.getString("location1")+" "+jsonObject.getString("location2")+" "+jsonObject.getString("location3");
locker_list.add(location);
}
} else {
}
} catch (JSONException e) {
e.printStackTrace();
}
}
};
Response.ErrorListener errorListener = new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
System.out.println(error);
}
};
getLoockerLocationRequest request = new getLoockerLocationRequest(responseListener,errorListener);
RequestQueue queue = Volley.newRequestQueue(PlaceOrderActivity.this);
queue.add(request);
}
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
System.out.println("selected item");
Toast.makeText(parent.getContext(),from_spinner.getSelectedItem().toString(),
Toast.LENGTH_SHORT).show();
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
System.out.println("nothing select");
String no_selected_value = "Select the location";
Toast.makeText(parent.getContext(),no_selected_value,
Toast.LENGTH_SHORT).show();
}
}

I solved the problem.
I don't know what is the concept of it. But if I add one extra item to the arraylist, no matter the item is "" (just blank/nothing inside) or "#######################################"
The program will became could run perfectly.
So I just add one locker_list.add(""); before the adapter create.
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_place_order);
locker_list.add("");
getLockerList();
from_spinner = (Spinner) findViewById(R.id.from_spinner);
from_spinner.setVisibility(View.VISIBLE);
ArrayAdapter adapter = new ArrayAdapter(this,android.R.layout.simple_spinner_item,locker_list);
from_spinner.setAdapter(adapter);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_dropdown_item);
from_spinner.setOnItemSelectedListener(this);
}

Selecting one from radio group value and scrolling down and some item selected automatically in Recycler View( beginner)

I am making an attendance system where I take the attendance using RadioGroup with two options. When I select some radio button and scroll down some other radio button gets auto-selected. If I change them upper ones also get changed.
Main class
public class TeacherAttendanceActivity extends AppCompatActivity implements AttendanceAdapter.AttendanceAdapterListner {
public static TeacherAttendanceActivity teacherAttendanceActivity;
private static final String TAG = TeacherAttendanceActivity.class.getSimpleName();
List<AttendanceModel> listItems;
private RecyclerView recyclerView;
private RecyclerView.Adapter adapter;
private AttendanceAdapter attendanceAdapter;
ProgressDialog progressDialog;
private SQLiteHandler db;
private SessionManager session;
private SearchView searchView;
Button btnSubmit;
JSONObject mainObj = new JSONObject();
// date
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String currentDateandTime = sdf.format(new Date());
String class_id,title;
Boolean Error;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_teacher_attendance);
//get data from intent
class_id = super.getIntent().getExtras().getString("id"); //class_id
title = super.getIntent().getExtras().getString("title");
getSupportActionBar().setTitle("Class: "+title+", Date: "+currentDateandTime );
// SqLite database handler
db = new SQLiteHandler(getApplicationContext());
// session manager
session = new SessionManager(getApplicationContext());
btnSubmit=findViewById(R.id.buttonAttendanceSubmit);
btnSubmit.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Error=false;
Gson gson=new Gson();
final String newDataArray=gson.toJson(listItems); // dataarray is list aaray
for (int i = 0; i < AttendanceAdapter.listItems.size(); i++){
if(AttendanceAdapter.listItems.get(i).getAttendance()==null){
Toast.makeText(TeacherAttendanceActivity.this, "Check attendance at roll:"+AttendanceAdapter.listItems.get(i).getRoll(), Toast.LENGTH_SHORT).show();
Error =true;
break;
}
}
if (!Error){
request(class_id,currentDateandTime,newDataArray);
}
}
});
listItems = new ArrayList<>();
attendanceAdapter = new AttendanceAdapter(listItems, this, (AttendanceAdapter.AttendanceAdapterListner) this);
recyclerView = (RecyclerView) findViewById(R.id.list_attendance);
recyclerView.setLayoutManager(new LinearLayoutManager(TeacherAttendanceActivity.this));
progressDialog = new ProgressDialog(this);
teacherAttendanceActivity = this;
//refresh_list(class_id);
}
#Override
protected void onStart() {
refresh_list(class_id);
super.onStart();
}
#Override
public void onAttendanceAdapterSelected(AttendanceModel model) {
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.refresh, menu);
getMenuInflater().inflate(R.menu.tool_bar, menu);
return true;
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
int id = item.getItemId();
switch (id){
case R.id.action_settings:
Toast.makeText(getApplicationContext(),"Sittings",Toast.LENGTH_LONG).show();
return true;
case R.id.action_logout:
logoutUser();
return true;
case R.id.action_about:
Toast.makeText(getApplicationContext(),"About",Toast.LENGTH_LONG).show();
return true;
case R.id.action_devinfo:
Toast.makeText(getApplicationContext(),"Dev info",Toast.LENGTH_LONG).show();
return true;
case R.id.refresh:
refresh_list(class_id);
return true;
default:
return super.onOptionsItemSelected(item);
}
}
void logoutUser() {
session.setLogin(false);
db.deleteUsers();
// Launching the login activity
Intent intent = new Intent(this, MainActivity.class);
startActivity(intent);
finish();
}
// refresh list
public void refresh_list(String id) {
// this method refresh list and get the json data
listItems.clear();
// adapter = new MyAdapter(listItems,getApplicationContext());
recyclerView.setAdapter(attendanceAdapter);
recyclerView.setItemAnimator(new DefaultItemAnimator());
progressDialog.setMessage("Loading");
progressDialog.show();
StringRequest stringRequest = new StringRequest(Request.Method.GET, ApiConfig.URL_TEACHER_ATTENDANCE+id, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
progressDialog.dismiss();
try {
progressDialog.hide();
JSONObject jsonObject = new JSONObject(response);
JSONArray jsonArray = jsonObject.getJSONArray("Data"); // finding data
Log.d(TAG, String.valueOf(jsonObject));
int len = jsonArray.length();
for (int i = 0; i < len; i++) {
JSONObject o = jsonArray.getJSONObject(i);
AttendanceModel item = new AttendanceModel(
o.getString("id"),
o.getString("name"),
o.getString("roll"),
o.getString("class_id"),
o.getString("status"),
null
);
listItems.add(item);
//adapter = new MyAdapter(listItems,getApplicationContext());
recyclerView.setAdapter(attendanceAdapter); // setting them in list view
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
progressDialog.hide();
Toast.makeText(TeacherAttendanceActivity.this, "Failed", Toast.LENGTH_SHORT).show();
}
}) {
/** Passing some request headers* */
#Override
public Map getHeaders() throws AuthFailureError {
SQLiteHandler db = new SQLiteHandler(getApplicationContext());
HashMap<String,String> userDetail= db.getUserDetails();
String userToken = userDetail.get("token");
Log.d(TAG, String.valueOf(userToken));
HashMap headers = new HashMap();
headers.put("Accept", "application/json");
headers.put("Authorization", "Bearer "+userToken);
return headers;
}
};
stringRequest.setShouldCache(false);
VolleyRequest.getInstance(TeacherAttendanceActivity.this).addToRequestQueue(stringRequest);
}
// take attendance
private void request( final String classId,final String date,final String data ) {
progressDialog.setMessage("Taking attendance");
showDialog();
StringRequest strReq = new StringRequest(Request.Method.POST,
ApiConfig.URL_TEACHER_ATTENDANCE_STORE, new Response.Listener<String>() {
#Override
public void onResponse(String response) {
Log.d(TAG, "Login Response: " + response);
hideDialog();
try {
JSONObject jObj = new JSONObject(response);
boolean error = jObj.getBoolean("error");
// Check for error node in json
if (!error) {
String attendance = jObj.getString("Attendance");
Toast.makeText(TeacherAttendanceActivity.this, attendance, Toast.LENGTH_LONG).show();
finish();
} else {
// Error in login. Get the error message
String errorMsg = jObj.getString("message");
Toast.makeText(TeacherAttendanceActivity.this,
errorMsg, Toast.LENGTH_LONG).show();
}
} catch (JSONException e) {
// JSON error
e.printStackTrace();
Toast.makeText(TeacherAttendanceActivity.this, "Json error: " + e.getMessage(), Toast.LENGTH_LONG).show();
}
}
}, new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Log.e(TAG, "Login Error: " + error.getMessage());
Toast.makeText(TeacherAttendanceActivity.this,
error.getMessage(), Toast.LENGTH_LONG).show();
hideDialog();
}
}) {
/** Passing some request headers* */
#Override
public Map getHeaders() throws AuthFailureError {
SQLiteHandler db = new SQLiteHandler(TeacherAttendanceActivity.this);
HashMap<String,String> userDetail= db.getUserDetails();
String userToken = userDetail.get("token");
Log.d(TAG, String.valueOf(userToken));
HashMap headers = new HashMap();
headers.put("Accept", "application/json");
headers.put("Authorization", "Bearer "+userToken);
return headers;
}
#Override
protected Map<String, String> getParams() {
// Posting parameters to login url
Map<String, String> params = new HashMap<String, String>();
params.put("class_id", classId);
params.put("date", date);
params.put("data", data);
return params;
}
};
strReq.setShouldCache(false);
// Adding request to request queue
VolleyRequest.getInstance(TeacherAttendanceActivity.this).addToRequestQueue(strReq);
}
private void showDialog() {
if (!progressDialog.isShowing())
progressDialog.show();
}
private void hideDialog() {
if (progressDialog.isShowing())
progressDialog.dismiss();
}
}
Model class
'model class for convenient '
public class AttendanceModel {
String id,name,roll,classId,previousAttendance,attendance;
public AttendanceModel(String id, String name,String roll, String classId,String previousAttendance,String attedance ){
this.id = id;
this.name = name;
this.classId =classId;
this.roll=roll;
this.attendance=attedance;
this.previousAttendance=previousAttendance;
}
public String getAttendance() {
return attendance;
}
public String getId() {
return id;
}
public String getName() {
return name;
}
public String getRoll() {
return roll;
}
public String getClassId() {
return classId;
}
public String getPreviousAttendance(){return previousAttendance;}
public void setId(String id) {
this.id = id;
}
public void setName(String name) {
this.name = name;
}
public void setRoll(String roll) {
this.roll = roll;
}
public void setClassId(String classId) {
this.classId = classId;
}
public void setPreviousAttendance(String previousAttendance) {
this.previousAttendance = previousAttendance;
}
public void setAttendance(String attendance) {
this.attendance = attendance;
}
}
Adapter class
' adapter class '
public class AttendanceAdapter extends RecyclerView.Adapter<AttendanceAdapter.ViewHolder> implements Filterable
{
// date
SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
String currentDateandTime = sdf.format(new Date());
private static final String TAG = AttendanceAdapter.class.getSimpleName();
public static List<AttendanceModel> listItems;
private List<AttendanceModel> listItemsFiltered;
private Context context;
private ProgressDialog dialog;
private AttendanceAdapter.AttendanceAdapterListner listner;
private ProgressDialog pDialog;
private SQLiteHandler db;
public static JSONObject jo = new JSONObject();
public static JSONArray ja = new JSONArray();
public AttendanceAdapter(List<AttendanceModel> listItems, Context context, AttendanceAdapter.AttendanceAdapterListner listner) {
this.listItems = listItems;
this.listner=listner;
this.context = context;
this.listItemsFiltered =listItems;
// SqLite database handler
db = new SQLiteHandler(context);
// Progress dialog
pDialog = new ProgressDialog(context);
}
#Override
public Filter getFilter() {
return new Filter() {
#Override
protected FilterResults performFiltering(CharSequence charSequence) {
String charString = charSequence.toString();
if (charString.isEmpty()) {
listItemsFiltered = listItems;
} else {
List<AttendanceModel> filteredList = new ArrayList<>();
for (AttendanceModel row : listItems) {
// name match condition. this might differ depending on your requirement
// here we are looking for name or phone number match
if (row.getName().toUpperCase().contains(charSequence.toString().toUpperCase())||row.getName().toLowerCase().contains(charSequence.toString().toLowerCase())) {
filteredList.add(row);
}
}
listItemsFiltered = filteredList;
}
FilterResults filterResults = new FilterResults();
filterResults.values = listItemsFiltered;
return filterResults;
}
#Override
protected void publishResults(CharSequence charSequence, FilterResults filterResults) {
listItemsFiltered = (ArrayList<AttendanceModel>) filterResults.values;
notifyDataSetChanged();
}
};
}
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView name;
public TextView roll;
public TextView previous;
RadioGroup radioAttendance;
RadioButton radioAttendancePresent,radioAttendanceAbsent;
public CardView card_view;
public ViewHolder(View itemView) {
super(itemView);
name= (TextView) itemView.findViewById(R.id.textViewAttendanceStudentName);
roll = (TextView) itemView.findViewById(R.id.textViewAttendanceStudentRoll);
previous = (TextView) itemView.findViewById(R.id.textViewAttendanceStudentPreviousStatus);
radioAttendance = itemView.findViewById(R.id.radioAttendance);
radioAttendancePresent =itemView.findViewById(R.id.radioAttendancePresent);
radioAttendanceAbsent =itemView.findViewById(R.id.radioAttendanceAbsent);
//card_view = (CardView) itemView.findViewById(R.id.class_card_view); // card view for on click method
itemView.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick( View view) {
// send selected contact in callback
listner.onAttendanceAdapterSelected(listItemsFiltered.get(getAdapterPosition())); // selecting cardview and position (model)
}
});
radioAttendance.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
//Toast.makeText(TeacherAttendanceActivity.this, toString(i), Toast.LENGTH_SHORT).show();
// Toast.makeText(context,"clicked at position"+i+" "+id+""+name,Toast.LENGTH_SHORT).show();
if(radioAttendancePresent.isChecked())
{
listItems.get(getAdapterPosition()).setAttendance("present");
}
else {
listItems.get(getAdapterPosition()).setAttendance("absent");
}
}
});
}
}
#Override
public AttendanceAdapter.ViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View v = LayoutInflater.from(parent.getContext()).inflate(R.layout.attendance_list, parent, false);
return new AttendanceAdapter.ViewHolder(v);
}
#Override
public void onBindViewHolder (final AttendanceAdapter.ViewHolder holder, final int position) {
final AttendanceModel listItem = listItemsFiltered.get(position);
holder.name.setText(listItem.getName());
holder.roll.setText(listItem.getRoll());
holder.previous.setText(listItem.getPreviousAttendance());
}
public interface AttendanceAdapterListner {
void onAttendanceAdapterSelected(AttendanceModel model); // sending cardview to say the dialoge and model for sending context
}
#Override
public int getItemCount() {
return listItemsFiltered.size();
}
private void showDialog() {
if (!pDialog.isShowing())
pDialog.show();
}
private void hideDialog() {
if (pDialog.isShowing())
pDialog.dismiss();
}
}

Your problem would be solved by making small changes to your Recycler view adapter, please do not disable recyclable property, this makes your recycler view a glorified list view.
I can see you tried using a sparse boolean array to hold the state of the radio buttons, that is good but you do not need that too. The idea behind using a Sparse boolean array is to keep the state of each item in the recycler view so that when they are recycled you still have a reference to what the state of each item is.
In your adapter you already have something that we can use to know the state, that is the attendance property of your model, in that case, you can set the state of your checkboxes by checking if the attendance property is present or absent.
One more thing about your code is that you are using the onCheckChangedListener as a click event handler for your radio button, you should not use this because it responds to all check changed events, even if it is triggered from code and not from user action, so when you bind your view and you set any of your radio buttons as checked or unchecked, it calls this callback.
Here is a modified version of your ViewHolder class that solves this issue by applying the solution above.
public class ViewHolder extends RecyclerView.ViewHolder {
public TextView name;
public TextView roll;
public TextView previous;
RadioGroup radioAttendance;
RadioButton radioAttendancePresent, radioAttendanceAbsent;
public CardView card_view;
public ViewHolder(View itemView) {
super(itemView);
name = (TextView) itemView.findViewById(R.id.textViewAttendanceStudentName);
roll = (TextView) itemView.findViewById(R.id.textViewAttendanceStudentRoll);
previous = (TextView) itemView.findViewById(R.id.textViewAttendanceStudentPreviousStatus);
radioAttendance = itemView.findViewById(R.id.radioAttendance);
radioAttendancePresent = itemView.findViewById(R.id.radioAttendancePresent);
radioAttendanceAbsent = itemView.findViewById(R.id.radioAttendanceAbsent);
radioAttendancePresent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
radioAttendancePresent.setChecked(true);
listItems.get(getAdapterPosition()).setAttendance("present");
}
});
radioAttendanceAbsent.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
radioAttendanceAbsent.setChecked(true);
listItems.get(getAdapterPosition()).setAttendance("absent");
}
});
}
void bind(int position) {
// use the sparse boolean array to check
if (listItems.get(position).getAttendance() != null) {
if (listItems.get(position).getAttendance().equals("present")) {
radioAttendancePresent.setChecked(true);
} else if (listItems.get(position).getAttendance().equals("absent")) {
radioAttendanceAbsent.setChecked(true);
}
} else {
radioAttendance.clearCheck();
}
name.setText(listItems.get(position).getName());
roll.setText(listItems.get(position).getRoll());
previous.setText(listItems.get(position).getPreviousAttendance());
}
}
Notice that we have separate click listener for each radio button and set the state in the list of items and just check that state when we are binding, also we have removed the onCheckChangedListener and the sparse boolean array, one last thing is that we made sure that when there is not state set for the attendance property, we just clear the radio buttons so that no one is selected the code is much simpler and works correctly now.

You have to initialize your RadioButton based on model state like below:
#Override
public void onBindViewHolder (final AttendanceAdapter.ViewHolder holder, final int position) {
final AttendanceModel listItem = listItemsFiltered.get(position);
holder.name.setText(listItem.getName());
holder.roll.setText(listItem.getRoll());
holder.previous.setText(listItem.getPreviousAttendance());
final String id =listItem.getId();
final String class_id =listItem.getClassId();
holder.radioAttendance.setOnCheckedChangeListener(null);
if(listItem.getAttendance().equalsIgnoreCase("present")) {
radioAttendancePresent.setChecked(true);
} else {
radioAttendancePresent.setChecked(false);
}
//Add listener here and remove from holder
holder.radioAttendance.setOnCheckedChangeListener(new RadioGroup.OnCheckedChangeListener() {
#Override
public void onCheckedChanged(RadioGroup radioGroup, int i) {
if(holder.radioAttendancePresent.isChecked()) {
listItemsFiltered.get(position).setAttendance("present");
} else {
listItemsFiltered.get(position).setAttendance("absent");
}
notifyDataSetChanged();
}
});
}

Android: Save Selected Items from spinner to SharedPreferences

from my question above, I actually want to test the existing codes that I from the Internet. I succesffuly can grab the data from a column in a table and shows back the data. For example, I when i choose person name's "Lim AI Khoon" the it wil display Lim Ai Khoon Names, and also Lim Ai Khoon's badge ID on the same activity. Now, how can I save the data that had being selected to sharedPreferences and display the data at next activity? Below is my code
//MainActivity.java
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
//Initializing the ArrayList
students = new ArrayList<String>();
//Initializing Spinner
spinner = (Spinner) findViewById(R.id.spinner);
//Adding an Item Selected Listener to our Spinner
//As we have implemented the class Spinner.OnItemSelectedListener to this class iteself we are passing this to setOnItemSelectedListener
spinner.setOnItemSelectedListener(this);
//Initializing TextViews
tvName = (TextView) findViewById(R.id.tvName);
tvBadgeID = (TextView) findViewById(R.id.tvBadgeID);
btnNext = findViewById(R.id.btnNext);
//This method will fetch the data from the URL
getData();
btnNext.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, Main2Activity.class);
startActivity(intent);
}
});
}
private void getData(){
//Creating a string request
StringRequest stringRequest = new StringRequest(Config.DATA_URL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
JSONObject j = null;
try {
//Parsing the fetched Json String to JSON Object
j = new JSONObject(response);
//Storing the Array of JSON String to our JSON Array
result = j.getJSONArray(Config.JSON_ARRAY);
//Calling method getStudents to get the students from the JSON Array
getStudents(result);
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
//Creating a request queue
RequestQueue requestQueue = Volley.newRequestQueue(this);
//Adding request to the queue
requestQueue.add(stringRequest);
}
private void getStudents(JSONArray j){
//Traversing through all the items in the json array
for(int i=0;i<j.length();i++){
try {
//Getting json object
JSONObject json = j.getJSONObject(i);
//Adding the name of the student to array list
students.add(json.getString(Config.TAG_NAME));
} catch (JSONException e) {
e.printStackTrace();
}
}
//Setting adapter to show the items in the spinner
spinner.setAdapter(new ArrayAdapter<String>(MainActivity.this, android.R.layout.simple_spinner_dropdown_item, students));
SharedPreferences sharedPref = getSharedPreferences("MyData", MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPref.edit();
editor.putString("reviewer",spinner.getSelectedItem().toString());
}
//Method to get student name of a particular position
private String getName(int position){
String name="";
try {
//Getting object of given index
JSONObject json = result.getJSONObject(position);
//Fetching name from that object
name = json.getString(Config.TAG_NAME);
} catch (JSONException e) {
e.printStackTrace();
}
//Returning the name
return name;
}
//Doing the same with this method as we did with getName()
private String getCourse(int position){
String course="";
try {
JSONObject json = result.getJSONObject(position);
course = json.getString(Config.TAG_BADGEID);
} catch (JSONException e) {
e.printStackTrace();
}
return course;
}
//this method will execute when we pic an item from the spinner
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
//Setting the values to textviews for a selected item
tvName.setText(getName(position));
tvBadgeID.setText(getCourse(position));
}
//When no item is selected this method would execute
#Override
public void onNothingSelected(AdapterView<?> parent) {
tvName.setText("");
tvBadgeID.setText("");
}
//Config.java
public class Config {
//JSON URL
public static final String DATA_URL = "http://10.0.2.2/spinner/getData.php";
//Tags used in the JSON String
public static final String TAG_NAME = "name";
public static final String TAG_BADGEID = "badgeid";
//JSON array name
public static final String JSON_ARRAY = "result";}

You missed one step,after this
editor.putString("reviewer",spinner.getSelectedItem().toString());
you need save the change ,put this line below :
editor.commit();
with that should work.

Android Studio: spinner is not displaying the information from the database

Using Android Studio, I created an activity which consists of a form that allows the user to add items to the database in the table which the user wishes. In terms of design, everything works well so far. I am using spinner in order to retrieve a particular column from a table and display the data in the spinner, however, whenever I run the application on Emulator/smartphone it does not display the data which I retrieved from the database (connection to the database was indeed successful and the data was outputted in json format in web browser). Any suggestions on this? Many thanks.
On a different laptop, a new android studio project was created and the code which I've shown here was run for testing purposes. Apparently, the spinner worked when I tried this, I have no idea why but I suspected different Gradle or Android studio versions?
public class add_activity extends AppCompatActivity {
private int PICK_IMAGE_REQUEST = 1;
private static final String typearray = "type_name";
private static final String type = "type_name";
private static final String JSON_ARRAY ="result";
private JSONArray result;
private Button btn_choose ;
Spinner spinner;
private ArrayList<String> arrayList;
TextView food_type;
String type_name;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_add);
btn_choose = findViewById(R.id.btn_choosedesign);
this.spinner = (Spinner) findViewById(R.id.spinnertype);
food_type = (TextView) findViewById(R.id.hiddentype);
// findViewById(R.id.hiddentype).setVisibility(View.GONE);
arrayList = new ArrayList<String>();
getdata();
spinner.setOnItemSelectedListener(new AdapterView.OnItemSelectedListener() {
#Override
public void onItemSelected(AdapterView<?> parent, View view, int position, long id) {
//Setting the values to textviews for a selected item
food_type.setText(getlocation(position));
}
#Override
public void onNothingSelected(AdapterView<?> parent) {
food_type.setText("");
}
});
btn_choose.setOnClickListener(new View.OnClickListener() {
...
}
});
}
private void showFileChooser() {
...
}
private void getdata() {
StringRequest stringRequest = new StringRequest("http://.../.../gettype.php",
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
JSONObject j = null;
try {
j = new JSONObject(response);
result = j.getJSONArray(JSON_ARRAY);
details(result);
} catch (JSONException e) {
e.printStackTrace();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
}
});
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
private void details(JSONArray j) {
for (int i = 0; i < j.length(); i++) {
try {
JSONObject json = j.getJSONObject(i);
arrayList.add(json.getString(typearray));
} catch (JSONException e) {
e.printStackTrace();
}
}
this.spinner.setAdapter(new ArrayAdapter<>(add_activity.this, android.R.layout.simple_spinner_dropdown_item, arrayList));
}
//Method to get location name which user selects
private String getlocation(int position) { // method is used to post name of marker to database accordingly
String loc = "";
try {
//Getting object of given index
JSONObject json = result.getJSONObject(position);
//Fetching location from that object
loc = json.getString(type);
} catch (JSONException e) {
e.printStackTrace();
}
//Return location
return loc;
}
}

How can I make sharedpreferences in Custom Adapter get the latest values of my ArrayList?

I use Volley in the onCreate of my Activity which gets a string on my server, then I convert this string to an arraylist,checkedContactsAsArrayList, and I pass it over to my custom adapter using sharedpreferences, which does stuff with the arraylist in the listview.
But the custom adapter keeps getting the previous arraylist in sharedpreferences, not the one I've just got from the server. The Volley call is too late or something - I can see in logcat the latest values are put after they are got, if you know what I mean.
For example:
VolleyCall 1 putString: 1,2,3
VolleyCall 2 putString: 4,5,6
VolleyCall 3 putString: 7,8,9
Custom Adapter 1 getString: gets values of the last time app was used
Custom Adapter 2 getString: 1,2,3
Custom Adapter 3 getString: 4,5,6
Any idea how to fix this? I could try doing the Volley call in the getView of my custom adapter but I've read on Stackoverflow that's bad practice.
Here are the relvant parts of my code - I've slimmed it down a bit, as there's a lot of stuff in there irrelevant to this issue.
Here's the code of my activity, ViewContact:
public class ViewContact extends AppCompatActivity implements android.widget.CompoundButton.OnCheckedChangeListener {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(activity_view_contact);
//selectPhoneContacts is an empty array list that will hold our SelectPhoneContact info
selectPhoneContacts = new ArrayList<SelectPhoneContact>();
listView = (ListView) findViewById(R.id.listviewPhoneContacts);
StringRequest stringRequest = new StringRequest(Request.Method.POST, ViewContact_URL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
//toast the response of ViewContact.php, which has been converted to a
//JSON object by the Php file with JSON encode
Toast.makeText(ViewContact.this, "OnResponse is" + response, Toast.LENGTH_LONG).show();
System.out.println("ViewContact: And the response is " + response);
try {
//checkedContacts is a String
String checkedContacts = responseObject.getString("checkedcontacts");
//convert the checkedContacts string to an arraylist
checkedContactsAsArrayList = new ArrayList<String>(Arrays.asList(checkedcontacts.split(",")));
System.out.println("ViewContact: checkedContactsAsArrayList is " + checkedContactsAsArrayList);
//we want to bring the checkedContactsAsArrayList array list to our SelectPhoneContactAdapter.
// It looks like Shared Preferences
//only works easily with strings so best way to bring the array list in Shared Preferences is with
//Gson.
//Here, we PUT the arraylist into the sharedPreferences
SharedPreferences sharedPreferencescheckedContactsAsArrayList = PreferenceManager.getDefaultSharedPreferences(getApplication());
SharedPreferences.Editor editorcheckedContactsAsArrayList = sharedPreferencescheckedContactsAsArrayList.edit();
Gson gsoncheckedContactsAsArrayList = new Gson();
String jsoncheckedContactsAsArrayList = gsoncheckedContactsAsArrayList.toJson(checkedContactsAsArrayList);
editorcheckedContactsAsArrayList.putString("checkedContactsAsArrayList", jsoncheckedContactsAsArrayList);
editorcheckedContactsAsArrayList.commit();
System.out.println("ViewContact: jsoncheckedContactsAsArrayList is " + jsoncheckedContactsAsArrayList);
} catch (JSONException e) {
e.printStackTrace();
Toast.makeText(getApplicationContext(),
"Error: " + e.getMessage(),
Toast.LENGTH_LONG).show();
}
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(ViewContact.this, error.toString(), Toast.LENGTH_LONG).show();
}
}) {
#Override
protected Map<String, String> getParams() {
Map<String, String> params = new HashMap<String, String>();
//we are posting review_id into our ViewContact.php file, which
//we get when a row is clicked in populistolistview
//to get matching details
params.put("review_id", review_id);
return params;
}
};
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
#Override
public void onCheckedChanged(CompoundButton buttonView, boolean isChecked) {
//checkBoxforContact.setChecked(true);
}
//******for the phone contacts in the listview
// Load data in background
class LoadContact extends AsyncTask<Void, Void, Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... voids) {
//we want to delete the old selectContacts from the listview when the Activity loads
//because it may need to be updated and we want the user to see the updated listview,
//like if the user adds new names and numbers to their phone contacts.
selectPhoneContacts.clear();
SelectPhoneContact selectContact = new SelectPhoneContact();
selectContact.setName(phoneNameofContact);
}
return null;
}
#Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
adapter = new SelectPhoneContactAdapter(selectPhoneContacts, ViewContact.this,0);
listView.setAdapter(adapter);
adapter.notifyDataSetChanged();
}
}
#Override
protected void onResume() {
super.onResume();
// getPrefs();
ViewContact.LoadContact loadContact = new ViewContact.LoadContact();
loadContact.execute();
Toast.makeText(ViewContact.this, "resuming!", Toast.LENGTH_SHORT).show();
}
}
And my custom adapter, SelectPhoneContactAdapter :
public class SelectPhoneContactAdapter extends BaseAdapter {
//define a list made out of SelectPhoneContacts and call it theContactsList
public List<SelectPhoneContact> theContactsList;
//define an array list made out of SelectContacts and call it arraylist
private ArrayList<SelectPhoneContact> arraylist;
Context _c;
ArrayList<String> MatchingContactsAsArrayList;
ArrayList<String> checkedContactsAsArrayList;
ArrayList <String> allNamesofContacts;
String contactToCheck;
//we will run through different logic in this custom adapter based on the activity that is passed to it
private int whichactivity;
String phoneNumberofContact;
String[] phoneNumberofContactStringArray;
String ContactsString;
Intent intent;
public SelectPhoneContactAdapter(final List<SelectPhoneContact> selectPhoneContacts, Context context, int activity) {
theContactsList = selectPhoneContacts;
_c = context;
this.arraylist = new ArrayList<SelectPhoneContact>();
this.arraylist.addAll(theContactsList);
whichactivity = activity;
//we are fetching the array list checkedContactsAsArrayList, created in ViewContact.
//with this we will put a tick in the checkboxes of contacts the review is being shared with
SharedPreferences sharedPreferencescheckedContactsAsArrayList = PreferenceManager.getDefaultSharedPreferences(_c);
Gson gsoncheckedContactsAsArrayList = new Gson();
String jsoncheckedContactsAsArrayList = sharedPreferencescheckedContactsAsArrayList.getString("checkedContactsAsArrayList", "");
Type type2 = new TypeToken<ArrayList<String>>() {
}.getType();
checkedContactsAsArrayList = gsoncheckedContactsAsArrayList.fromJson(jsoncheckedContactsAsArrayList, type2);
System.out.println("SelectPhoneContactAdapter checkedContactsAsArrayList :" + checkedContactsAsArrayList);
}
}
#Override
public int getCount() {
return arraylist.size();
}
#Override
public Object getItem(int i) {
return arraylist.get(i);
}
#Override
public long getItemId(int i) {
return i;
}
static class ViewHolder {
//In each cell in the listview show the items you want to have
//Having a ViewHolder caches our ids, instead of having to call and load each one again and again
TextView title, phone;
CheckBox check;
Button invite;
}
#Override
public View getView(final int i, View convertView, ViewGroup viewGroup) {
//this is the SelectPhoneContact object; consists of textboxes, buttons, checkbox
final SelectPhoneContact data = (SelectPhoneContact) arraylist.get(i);
ViewHolder holder = null;
if (convertView == null) {
//if there is nothing there (if it's null) inflate the view with the layout
LayoutInflater li = (LayoutInflater) _c.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
convertView = li.inflate(R.layout.phone_inflate_listview, null);
holder = new ViewHolder();
//So, for example, title is cast to the name id, in phone_inflate_listview,
//phone is cast to the id called no etc
holder.title = (TextView) convertView.findViewById(R.id.name);
holder.phone = (TextView) convertView.findViewById(R.id.no);
holder.invite = (Button) convertView.findViewById(R.id.btnInvite);
holder.check = (CheckBox) convertView.findViewById(R.id.checkBoxContact);
convertView.setTag(holder);
} else {
holder = (ViewHolder) convertView.getTag();
}
//in the listview for contacts, set the name
holder.title.setText(data.getName());
//in the listview for contacts, set the number
holder.phone.setText(data.getPhone());
holder.check.setTag(data);
return convertView;
}
}

Call this: loadContact.execute();
After you call .commit();
ViewContact.LoadContact loadContact = new ViewContact.LoadContact();
loadContact.execute();