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Android studio onItemClick displaying grey

I have a project, controlling a jetski from a far with a android application using Bluetooth.
I have made 2 files:
Here is the "Peripherique.java" (the Bluetooth thing):
package com.example.btjetski;
import androidx.appcompat.app.AppCompatActivity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothDevice;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import java.util.ArrayList;
import java.util.Set;
public class Peripherique extends AppCompatActivity {
Button btnPaired;
ListView devicelist;
private BluetoothAdapter myBluetooth;
private Set<BluetoothDevice> pairedDevices;
public static String EXTRA_ADDRESS = "device_address";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
btnPaired = findViewById(R.id.button);
devicelist = findViewById(R.id.listView);
myBluetooth = BluetoothAdapter.getDefaultAdapter();
if (myBluetooth == null) {
Toast.makeText(getApplicationContext(), "Périphérique Bluetooth non disponible", Toast.LENGTH_LONG).show();
finish();
} else if (!myBluetooth.isEnabled()) {
Intent turnBTon = new
Intent(BluetoothAdapter.ACTION_REQUEST_ENABLE);
startActivityForResult(turnBTon, 1);
}
btnPaired.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
list();
}
});
}
private void list() { // écouter les périphériques BT
pairedDevices = myBluetooth.getBondedDevices();
ArrayList list = new ArrayList();
if (pairedDevices.size() > 0) {
for (BluetoothDevice bt : pairedDevices) {
list.add(bt.getName() + "\n" + bt.getAddress());
}
} else {
Toast.makeText(getApplicationContext(), "Aucun des appareils trouvés", Toast.LENGTH_LONG).show();
}
ArrayAdapter adapter = new ArrayAdapter(this, android.R.layout.simple_list_item_1, list);
devicelist.setAdapter(adapter);
}
public void onItemClick(AdapterView<?> av, View v, int arg2, long arg3)
{
String info = ((TextView) v).getText().toString();
String address = info.substring(info.length() - 17);
Intent i = new Intent(Peripherique.this, jetControl.class);
i.putExtra(EXTRA_ADDRESS, address);
startActivity(i);
}
}
Here is jetControl.java
package com.example.btjetski;
import android.app.ProgressDialog;
import android.os.Bundle;
import androidx.appcompat.app.AppCompatActivity;
import android.bluetooth.BluetoothAdapter;
import android.bluetooth.BluetoothSocket;
import android.content.Intent;
import android.view.View;
import android.widget.Button;
import java.io.IOException;
import java.util.UUID;
public class jetControl extends AppCompatActivity {
Button buttonON1, buttonOFF1;
String address = null;
private ProgressDialog progress;
BluetoothAdapter myBluetooth = null;
BluetoothSocket btSocket = null;
private boolean isBtConnected = false;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
Intent newint = getIntent();
address = newint.getStringExtra(Peripherique.EXTRA_ADDRESS); //recevoir l'adresse du périphérique BT
setContentView(R.layout.activity_jet_control);
//WIDGETS
Button buttonON1 = findViewById(R.id.buttonON1);
Button buttonOFF1 = findViewById(R.id.buttonOFF1);
setOnClickListener();
}
private void setOnClickListener() {
buttonON1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
AllumerJetski1();
}
});
buttonOFF1.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
EteindreJetski1();
}
});
}
private void AllumerJetski1() {
if (btSocket != null) {
try {
btSocket.getOutputStream().write("A".toString().getBytes());
} catch (IOException e) {
}
}
}
private void EteindreJetski1() {
if (btSocket != null) {
try {
btSocket.getOutputStream().write("a".toString().getBytes());
} catch (IOException e) {
}
}
}
}
When the app starts, i can connect to my ESP32 but nothing happens, i should have an overlay that shows up with two buttons "ON/OFF" but nothing seems to work properly.
I thank you so much for your help.

(Android) When Back pressed, Attempt to invoke virtual method 'int java.lang.String.hashCode()' on a null object reference

I've been working on a Android Project (A Basic College Information App), I have three main activities, the user goes in like, Goal/Course Select activity-> CollegeList activity-> College Details Activity. Now When I press back on College Details Activity it crashes with this Error:
Attempt to invoke virtual method 'int java.lang.String.hashCode()' on a null object reference
Below are the files/code which I think might be responsible for this.....
CollegeListActivity.java file
package com.anurag.college_information.activities;
import static com.anurag.college_information.activities.CareerGoalActivity.GOAL;
import static com.anurag.college_information.activities.CareerGoalActivity.SHARED_PREFS;
import android.app.AlertDialog;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.TextView;
import androidx.appcompat.app.AppCompatActivity;
import androidx.recyclerview.widget.LinearLayoutManager;
import androidx.recyclerview.widget.RecyclerView;
import com.anurag.college_information.R;
import com.anurag.college_information.adapters.RecyclerAdapter;
import com.anurag.college_information.models.ModelClass;
import java.util.ArrayList;
import java.util.List;
public class CollegeListActivity extends AppCompatActivity {
private RecyclerAdapter.RecyclerViewClickListener listener;
//ListView collegeList;
TextView collegeListTitle;
Button courseChange;
RecyclerView recyclerView;
LinearLayoutManager LayoutManager;
RecyclerAdapter recyclerAdapter;
List<ModelClass> cList;
String courseName;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_college_list);
collegeListTitle = findViewById(R.id.college_list_title);
courseChange = findViewById(R.id.btn_change_course);
//collegeListTitle.setText(goal + "Colleges");
collegeListTitle.setText(getIntent().getStringExtra("Title") + " Colleges");
initData();
initRecyclerView();
//collegeList = findViewById(R.id.lv_college_list);
courseChange.setTransformationMethod(null);
courseChange.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
SharedPreferences sharedPreferences = getSharedPreferences(SHARED_PREFS, MODE_PRIVATE);
SharedPreferences.Editor editor = sharedPreferences.edit();
editor.clear();
editor.apply();
Intent i = new Intent(CollegeListActivity.this, CareerGoalActivity.class);
startActivity(i);
//finish();
}
});
}
private void initData() {
cList = new ArrayList<>();
courseName = getIntent().getStringExtra("Title");
switch (courseName) {
case "BE/BTech":
cList.add(new ModelClass("https://images.static-collegedunia.com/public/college_data/images/campusimage/1479294300b-5.jpg", "A.P. Shah College of Engineering", "Thane", "8.0"));
break;
case "Pharmacy":
cList.add(new ModelClass("https://images.static-collegedunia.com/public/college_data/images/campusimage/14382400753.jpg", "Bombay College Of Pharmacy", "Mumbai", "9.0"));
break;
}
}
private void initRecyclerView() {
setOnClickListener();
recyclerView = findViewById(R.id.recycler_view);
LayoutManager = new LinearLayoutManager(this);
LayoutManager.setOrientation(RecyclerView.VERTICAL);
recyclerView.setLayoutManager(LayoutManager);
recyclerAdapter = new RecyclerAdapter(cList, listener);
recyclerView.setAdapter(recyclerAdapter);
}
private void setOnClickListener() {
listener = new RecyclerAdapter.RecyclerViewClickListener() {
#Override
public void onClick(View v, int position) {
Intent i = new Intent(CollegeListActivity.this, CollegeDetailsActivity.class);
startActivity(i);
}
};
}
#Override
public void onBackPressed() {
new AlertDialog.Builder(this)
.setMessage("Are you sure you want to exit?")
.setPositiveButton("Yes", new DialogInterface.OnClickListener() {
public void onClick(DialogInterface dialog, int id) {
finish();
}
})
.setNegativeButton("No", null)
.show();
}
}
RecyclerAdapter.java
package com.anurag.college_information.adapters;
import android.content.Context;
import android.content.Intent;
import android.telecom.Call;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ImageView;
import android.widget.TextView;
import androidx.annotation.NonNull;
import androidx.recyclerview.widget.RecyclerView;
import com.anurag.college_information.activities.CollegeDetailsActivity;
import com.anurag.college_information.models.ModelClass;
import com.anurag.college_information.R;
import com.squareup.picasso.Picasso;
import java.util.List;
public class RecyclerAdapter extends RecyclerView.Adapter<RecyclerAdapter.ViewHolder> {
private List<ModelClass> collegeList ;
private RecyclerViewClickListener listener;
List<String> imageUrl, collegeName, collegeLocation, collegeRating;
public RecyclerAdapter(List<ModelClass> collegeList, RecyclerViewClickListener listener){
this.collegeList=collegeList;
this.listener = listener;
}
#NonNull
#Override
public RecyclerAdapter.ViewHolder onCreateViewHolder(#NonNull ViewGroup parent, int viewType) {
View view = LayoutInflater.from(parent.getContext()).inflate(R.layout.college_list_single_row, parent, false);
return new ViewHolder(view);
}
#Override
public void onBindViewHolder(#NonNull RecyclerAdapter.ViewHolder holder, int position) {
String imageLink = collegeList.get(position).getImageLink();
//int img = collegeList.get(position).getCollegeImage();
String cName = collegeList.get(position).getCollegeName();
String cRating = collegeList.get(position).getCollegeRating();
String cLocation = collegeList.get(position).getLocation();
Picasso.get().load(imageLink).into(holder.imageView);
//holder.setData(img, cName, cRating);
holder.setData(imageLink, cName, cLocation ,cRating);
}
#Override
public int getItemCount() {
return collegeList.size();
}
public class ViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener {
private ImageView imageView;
private TextView collegeName, collegeRating, collegeLocation;
public ViewHolder(#NonNull View itemView) {
super(itemView);
imageView = itemView.findViewById(R.id.college_image);
collegeName = itemView.findViewById(R.id.college_name);
collegeRating = itemView.findViewById(R.id.college_rating);
collegeLocation = itemView.findViewById(R.id.college_location);
itemView.setOnClickListener(this);
}
public void setData(String imageLink, String cName, String cLocation, String cRating) {
//imageView.setImageResource(img);
Picasso.get().load(imageLink).error(R.drawable.error).into(imageView);
collegeName.setText(cName);
collegeRating.setText(cRating);
collegeLocation.setText(cLocation);
}
#Override
public void onClick(View v) {
listener.onClick(v, getAdapterPosition());
Intent i = new Intent(v.getContext(), CollegeDetailsActivity.class);
i.putExtra("collegeImage", collegeList.get(getAdapterPosition()).getImageLink());
i.putExtra("collegeName", collegeList.get(getAdapterPosition()).getCollegeName());
i.putExtra("collegeRating", collegeList.get(getAdapterPosition()).getCollegeRating());
i.putExtra("collegeLocation", collegeList.get(getAdapterPosition()).getLocation());
v.getContext().startActivity(i);
}
}
public interface RecyclerViewClickListener{
void onClick(View v, int position);
}
}
CollegeDetailsActivity.java
package com.anurag.college_information.activities;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.widget.Button;
import android.widget.ImageView;
import android.widget.TextView;
import android.widget.Toast;
import androidx.appcompat.app.AppCompatActivity;
import com.anurag.college_information.R;
import com.squareup.picasso.Picasso;
public class CollegeDetailsActivity extends AppCompatActivity {
Button btnApply;
ImageView dCollegeImage;
TextView dCollegeName, dCollegeRating, dCollegeLocation;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_college_details);
dCollegeImage = findViewById(R.id.details_college_image);
dCollegeName = findViewById(R.id.details_college_name);
dCollegeRating = findViewById(R.id.details_college_rating);
dCollegeLocation = findViewById(R.id.details_college_location);
btnApply = findViewById(R.id.btn_apply);
Intent i = getIntent();
String cn = i.getStringExtra("collegeName");
String cr = i.getStringExtra("collegeRating");
String ci = i.getStringExtra("collegeImage");
String cl = i.getStringExtra("collegeLocation");
Picasso.get().load(ci).error(R.drawable.error).into(dCollegeImage);
dCollegeName.setText(cn);
dCollegeRating.setText(cr);
dCollegeLocation.setText(cl);
btnApply.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Toast.makeText(getApplicationContext(), "The institute will be notified, of your application", Toast.LENGTH_LONG).show();
Toast.makeText(getApplicationContext(), "The college will contact you, Thank you", Toast.LENGTH_LONG).show();
}
});
}
#Override
public void onBackPressed() {
Intent i = new Intent(CollegeDetailsActivity.this, CollegeListActivity.class);
startActivity(i);
}
}
This is the Error Screenshot:
I'm pretty new to android I've just worked on just 4 to 5 projects,
Any Assistance will be appreciated, Thank You
The commented Out code, is just a normal listview I implemented just In Case, I have to remove the recycler view.

This will probably go away if you don't override onBackPressed in CollegeDetailsActivity. Instead of going back to an activity that had a valid "Title" string extra, the code you posted will go to a new activity where "Title" isn't defined, then get a NullPointerException since courseName will be null in initData (which the error message tells you results in an error on line 81 in that method). Using a null string in a switch results in that type of error
Just remove your onBackPressed entirely in CollegeDetailsActivity.

Testing android in app billing doesn't show any products when bebugging

I have a simple app that has an unlock feature in it. When a user purchases this they can unlock more content in the app.
When I debug the app I don't get any errors, but I am unable to retrieve a list of products using the google billing services.
On my main activity I would like to check if the user has all ready purchased the "upgrade" if they have do something with that information.
I have been following the api documentation but its not really helping.
In App Billing Reference
Implementation
Testing
I have 1 item in my In-app products, I have followed the testing document and added an apk to my Alpha testing. The problem here is that apk cant have debugging enabled, so when I use the debugger in android studio the app may perform differently??
I think my code is OK,but any help or guidance in how to test this would be great.
MainActivity.java
import android.app.Activity;
import android.content.ComponentName;
import android.content.Context;
import android.content.Intent;
import android.content.ServiceConnection;
import android.os.IBinder;
import android.os.RemoteException;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.util.Log;
import android.view.Menu;
import android.view.MenuItem;
import android.view.MotionEvent;
import android.view.View;
import android.widget.Button;
import com.android.vending.billing.IInAppBillingService;
import org.json.JSONException;
import org.json.JSONObject;
import java.util.ArrayList;
import java.util.List;
public class MainActivity extends Activity {
IInAppBillingService mService;
ServiceConnection connection;
Intent serviceIntent;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.home);
Button start = (Button) findViewById(R.id.startgame);
Button settings = (Button) findViewById(R.id.about);
start.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(getApplicationContext(), StartGame.class);
startActivity(i);
overridePendingTransition(R.anim.slide_in, R.anim.slide_out);
}
});
settings.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent i = new Intent(getApplicationContext(), Settings.class);
startActivity(i);
overridePendingTransition(R.anim.slide_in, R.anim.slide_out);
}
});
/// check for pro unlock
serviceIntent = new Intent("com.android.vending.billing.InAppBillingService.BIND");
serviceIntent.setPackage("com.android.vending");
// first this
connection = new ServiceConnection() {
#Override
public void onServiceDisconnected(ComponentName name) {
mService = null;
}
#Override
public void onServiceConnected(ComponentName name, IBinder service) {
Log.d("BILLING", "Connected");
//purchse info
mService = IInAppBillingService.Stub.asInterface(service);
checkPurchaseInfo();
}
};
bindService(serviceIntent, connection, Context.BIND_AUTO_CREATE);
}
private void checkPurchaseInfo() {
try {
Bundle ownedItems = mService.getPurchases(3, getPackageName(), "inapp", null);
int responseCode = ownedItems.getInt("RESPONSE_CODE");
Log.d("BILLING","Request Code: " + responseCode);
if(responseCode == 0){
ArrayList<String> ownedSkus = ownedItems.getStringArrayList("INAPP_PURCHASE_ITEM_LIST");
ArrayList<String> purchaseDataList = ownedItems.getStringArrayList("INAPP_PURCHASE_DATA_LIST");
ArrayList<String> signatureList = ownedItems.getStringArrayList("INAPP_DATA_SIGNATURE_LIST");
String continuationToken = ownedItems.getString("INAPP_CONTINUATION_TOKEN");
Log.d("OWNED",ownedSkus.toString());
Log.d("purcahseList",purchaseDataList.toString());
Log.d("SIGNLIST",signatureList.toString());
/////////
//all of these arrays come back as empty []
////////
}
} catch (RemoteException e) {
e.printStackTrace();
}
}
#Override
public void onDestroy() {
super.onDestroy();
if (connection != null) {
unbindService(connection);
}
}
}

I have two activity.When i was click on first activity list view,second activity open. number of count in first activity also increase

I have two activities. When I clicked on first activity in list view, second activity opened .Second activity have one button number of item. when I clicked on second activity number of count goes to first activity. It is repeated process but number of count in first activity also gets increased.
My first activity..
package com.firstchoicefood.phpexpertgroup.firstchoicefoodin;
import android.app.ActionBar;
import android.app.ProgressDialog;
import android.content.Intent;
import android.content.res.Resources;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.os.AsyncTask;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.MenuInflater;
import android.view.View;
import android.view.ViewGroup;
import android.view.Window;
import android.widget.AbsListView;
import android.os.Bundle;
import android.util.Log;
import android.view.ActionMode;
import android.view.Menu;
import android.view.MenuItem;
import android.widget.AdapterView;
import android.widget.ArrayAdapter;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import android.app.Activity;
import com.firstchoicefood.phpexpertgroup.firstchoicefoodin.adapter.ListAdapterAddItems;
import com.firstchoicefood.phpexpertgroup.firstchoicefoodin.bean.ListModel;
import com.firstchoicefood.phpexpertgroup.firstchoicefoodin.json.JSONfunctions;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.net.URLEncoder;
import java.util.ArrayList;
import android.support.v7.app.ActionBarActivity;
import android.os.Bundle;
import android.view.Menu;
import android.view.MenuItem;
public class DetaisRESTActivity extends Activity {
String messagevaluename,totalamount,valueid,valueid1,valuename,pos;
public String countString=null;
public int count=0;
public String message=null;
public static String message1=null;
JSONObject jsonobject;
JSONArray jsonarray;
ListView listview;
ArrayList aa;
public TextView mTitleTextView;
public ImageButton imageButton;
ListAdapterAddItems adapter;
public TextView restaurantname = null;
public TextView ruppees = null;
String restaurantmenuname,rastaurantname;
ProgressDialog mProgressDialog;
ArrayList<ListModel> arraylist;
public static String RASTAURANTNAMEDETAILS = "RestaurantPizzaItemName";
public static String RASTAURANTRUPPEES = "RestaurantPizzaItemPrice";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// requestWindowFeature(Window.FEATURE_CUSTOM_TITLE);
setContentView(R.layout.activity_detais_rest);
// getWindow().setFeatureInt(Window.FEATURE_CUSTOM_TITLE,R.layout.titlebar);
ActionBar actionBar = getActionBar();
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setBackgroundDrawable(new ColorDrawable(Color.parseColor("#ff0000")));
LayoutInflater mInflater = LayoutInflater.from(this);
View mCustomView = mInflater.inflate(R.layout.titlebar, null);
mTitleTextView = (TextView) mCustomView.findViewById(R.id.textView123456789);
imageButton = (ImageButton) mCustomView
.findViewById(R.id.imageButton2);
imageButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Toast.makeText(getApplicationContext(), "Refresh Clicked!",
Toast.LENGTH_LONG).show();
Intent i=new Intent(DetaisRESTActivity.this,TotalPriceActivity.class);
startActivity(i);
}
});
actionBar.setCustomView(mCustomView);
actionBar.setDisplayShowCustomEnabled(true);
Intent intent = getIntent();
// get the extra value
valuename = intent.getStringExtra("restaurantmenuname");
valueid = intent.getStringExtra("restaurantmenunameid");
valueid1 = intent.getStringExtra("idsrestaurantMenuId5");
//totalamount = intent.getStringExtra("ruppees");
Log.i("valueid",valueid);
Log.i("valuename",valuename);
Log.i("valueid1",valueid1);
// Log.i("totalamount",totalamount);
new DownloadJSON().execute();
}
// DownloadJSON AsyncTask
private class DownloadJSON extends AsyncTask<Void,Void,Void> {
#Override
protected void onPreExecute() {
super.onPreExecute();
// Create a progressdialog
mProgressDialog = new ProgressDialog(DetaisRESTActivity.this);
// Set progressdialog title
mProgressDialog.setTitle("Android JSON Parse Tutorial");
// Set progressdialog message
mProgressDialog.setMessage("Loading...");
mProgressDialog.setIndeterminate(false);
// Show progressdialog
mProgressDialog.show();
Toast.makeText(DetaisRESTActivity.this, "Successs", Toast.LENGTH_LONG).show();
}
#Override
protected Void doInBackground(Void... params) {
// Create an array
arraylist = new ArrayList<ListModel>();
// Retrieve JSON Objects from the given URL address
// Log.i("123",value1);
jsonobject = JSONfunctions.getJSONfromURL("http://firstchoicefood.in/fcfapiphpexpert/phpexpert_restaurantMenuItem.php?r=" + URLEncoder.encode(valuename) + "&resid=" + URLEncoder.encode(valueid1) + "&RestaurantCategoryID=" + URLEncoder.encode(valueid) + "");
try {
// Locate the array name in JSON
jsonarray = jsonobject.getJSONArray("RestaurantMenItems");
Log.i("1234",""+jsonarray);
for (int i = 0; i < jsonarray.length(); i++) {
jsonobject = jsonarray.getJSONObject(i);
ListModel sched = new ListModel();
sched.setId(jsonobject.getString("id"));
sched.setProductName(jsonobject.getString("RestaurantPizzaItemName"));
sched.setPrice(jsonobject.getString("RestaurantPizzaItemPrice"));
arraylist.add(sched);
}
} catch (JSONException e) {
Log.e("Error", e.getMessage());
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void args) {
// Locate the listview in listview_main.xml
listview = (ListView) findViewById(R.id.listViewdetails);
adapter = new ListAdapterAddItems();
listview.setAdapter(adapter);
// Close the progressdialog
mProgressDialog.dismiss();
//listview.invalidateViews();
adapter.notifyDataSetChanged();
// listview.notifyAll();
listview.setOnItemClickListener(new AdapterView.OnItemClickListener()
{
#Override
public void onItemClick(AdapterView<?> arg0, View arg1, int position, long arg3)
{
// Get Person "behind" the clicked item
ListModel p =(ListModel)listview.getItemAtPosition(position);
// Log the fields to check if we got the info we want
Log.i("SomeTag",""+p.getId());
//String itemvalue=(String)listview.getItemAtPosition(position);
Log.i("SomeTag", "Persons name: " + p.getProductName());
Log.i("SomeTag", "Ruppees: " + p.getPrice());
//count++;
//countString=String.valueOf(count);
Toast toast = Toast.makeText(getApplicationContext(),
"Item " + (position + 1),
Toast.LENGTH_SHORT);
toast.setGravity(Gravity.BOTTOM|Gravity.CENTER_HORIZONTAL, 0, 0);
toast.show();
//Toast.makeText(getBaseContext(),
// countString, Toast.LENGTH_LONG).show();
Log.i("postititi",""+position);
// mTitleTextView.setText(countString);
Intent intent=new Intent(DetaisRESTActivity.this,QuentityActivity.class);
intent.putExtra("quentity",countString);
intent.putExtra("valueid",valueid);
intent.putExtra("valuename",valuename);
intent.putExtra("valueid1",valueid1);
intent.putExtra("id",p.getId());
intent.putExtra("name",p.getProductName());
intent.putExtra("price",p.getPrice());
startActivityForResult(intent,2);
// startActivity(intent);
}
});
}
}
// Call Back method to get the Message form other Activity
#Override
protected void onActivityResult(int requestCode, int resultCode, Intent data)
{
super.onActivityResult(requestCode, resultCode, data);
// check if the request code is same as what is passed here it is 2
if(requestCode==2)
{
// aa=new ArrayList();
pos=data.getStringExtra("POSITION");
message=data.getStringExtra("MESSAGE");
message1=data.getStringExtra("COUNTSTRING");
messagevaluename=data.getStringExtra("VALUENAME");
Log.i("xxxxxxxxxxx",message);
Log.i("xxxxxxxxxxx1234",pos);
Log.i("xxxxxxxxxxx5678count",message1);
Log.i("messagevaluename",messagevaluename);
//ruppees.setText(message);
mTitleTextView.setText(message1);
imageButton.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View view) {
Toast.makeText(getApplicationContext(), message,
Toast.LENGTH_LONG).show();
Intent i=new Intent(DetaisRESTActivity.this,TotalPriceActivity.class);
i.putExtra("ruppees",message);
i.putExtra("id",pos);
i.putExtra("messagevaluename",messagevaluename);
startActivity(i);
}
});
}
}
//==========================
class ListAdapterAddItems extends ArrayAdapter<ListModel>
{
ListAdapterAddItems(){
super(DetaisRESTActivity.this,android.R.layout.simple_list_item_1,arraylist);
//imageLoader = new ImageLoader(MainActivity.this);
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
final ViewHolder holder;
if(convertView == null){
LayoutInflater inflater = getLayoutInflater();
convertView = inflater.inflate(R.layout.cartlistitem, null);
holder = new ViewHolder(convertView);
convertView.setTag(holder);
}else{
holder = (ViewHolder)convertView.getTag();
}
holder.populateFrom(arraylist.get(position));
// arraylist.get(position).getPrice();
return convertView;
}
}
class ViewHolder {
ViewHolder(View row) {
restaurantname = (TextView) row.findViewById(R.id.rastaurantnamedetailsrestaurant);
ruppees = (TextView) row.findViewById(R.id.rastaurantcuisinedetalsrestaurant);
}
// Notice we have to change our populateFrom() to take an argument of type "Person"
void populateFrom(ListModel r) {
restaurantname.setText(r.getProductName());
ruppees.setText(r.getPrice());
}
}
//=============================================================
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_detais_rest, menu);
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.
return super.onOptionsItemSelected(item);
}
}
Second activity....
package com.firstchoicefood.phpexpertgroup.firstchoicefoodin;
import android.app.ActionBar;
import android.app.Activity;
import android.app.ProgressDialog;
import android.content.Intent;
import android.graphics.Color;
import android.graphics.drawable.ColorDrawable;
import android.os.AsyncTask;
import android.os.Bundle;
import android.support.v4.app.FragmentManager;
import android.util.Log;
import android.view.Gravity;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.widget.AdapterView;
import android.widget.ImageButton;
import android.widget.ListView;
import android.widget.TextView;
import android.widget.Toast;
import com.firstchoicefood.phpexpertgroup.firstchoicefoodin.bean.ListModel;
import com.firstchoicefood.phpexpertgroup.firstchoicefoodin.json.JSONfunctions;
import org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import java.net.URLEncoder;
import java.util.ArrayList;
public class QuentityActivity extends Activity {
String value=null;
public String TotAmt=null;
String Name;
ImageButton positive,negative;
String position;
int count = 1;
int tot_amt = 0;
public String countString=null;
String Rs,name,price;
String valueid,valueid1,valuename;
JSONObject jsonobject;
JSONArray jsonarray;
ListView listview;
public TextView ruppees,submenuname,totalruppees,quantity,addtocart;
ProgressDialog mProgressDialog;
ArrayList<ListModel> arraylist;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_quentity);
ActionBar actionBar = getActionBar();
// Enabling Up / Back navigation
actionBar.setDisplayHomeAsUpEnabled(true);
actionBar.setBackgroundDrawable(new ColorDrawable(Color.parseColor("#ff0000")));
Intent intent = getIntent();
// get the extra value
value = intent.getStringExtra("quentity");
valuename = intent.getStringExtra("valuename");
valueid = intent.getStringExtra("valueid");
valueid1 = intent.getStringExtra("valueid1");
name=intent.getStringExtra("name");
price=intent.getStringExtra("price");
position=intent.getStringExtra("id");
Log.i("valueid",valueid);
Log.i("valuename",valuename);
Log.i("valueid1",valueid1);
Log.i("name",name);
Log.i("price",price);
Log.i("id1",position);
quantity=(TextView)findViewById(R.id.rastaurantcuisinedetalsrestaurantquantity);
totalruppees=(TextView)findViewById(R.id.rastaurantnamequentitytotal1);
submenuname=(TextView)findViewById(R.id.rastaurantnamesubmenuquentity);
ruppees=(TextView)findViewById(R.id.rastaurantnamequentity1);
positive=(ImageButton)findViewById(R.id.imageButtonpositive);
negative=(ImageButton)findViewById(R.id.imageButtonnegative);
addtocart=(TextView)findViewById(R.id.textViewaddtocart);
buttonclick();
addtocart();
// value1 = intent.getStringExtra("numericitem");
// int numericvalue = intent.getIntExtra("numericitem", 11);
submenuname.setText(name);
ruppees.setText(price);
totalruppees.setText(price);
// new DownloadJSON().execute();
}
public void buttonclick(){
positive.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String getString =quantity.getText().toString();
String totalAmtString = ruppees.getText().toString();
int totAmount = Integer.parseInt(totalAmtString);
//count = Integer.parseInt(getString);
count++;
countString = String.valueOf(count);
tot_amt = totAmount * count;
TotAmt = String.valueOf(tot_amt);
totalruppees.setText(TotAmt);
quantity.setText(countString);
}
});
negative.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
String getString =quantity.getText().toString();
String totalAmtString = ruppees.getText().toString();
int totAmount = Integer.parseInt(totalAmtString);
//count = Integer.parseInt(getString);
if (count > 1)
count--;
countString = String.valueOf(count);
tot_amt = totAmount * count;
TotAmt = String.valueOf(tot_amt);
totalruppees.setText(TotAmt);
quantity.setText(countString);
}
});
}
public void addtocart(){
addtocart.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Intent intent=new Intent();
intent.putExtra("MESSAGE",TotAmt);
intent.putExtra("POSITION",position);
intent.putExtra("COUNTSTRING",countString);
intent.putExtra("VALUENAME",valuename);
setResult(2,intent);
finish();//finishing activity
}
});
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.menu_quentity, menu);
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_settings) {
return true;
}
return super.onOptionsItemSelected(item);
}
}

How do I use setResult when returning from an activity?

I need help, I am making a simple application, and I don´t know how to return to the MainActivity the string from the spinner and the name of the person when i click in the "Aceptar" button.
MainActivity.java
package com.example.holaamigos;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.Menu;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.CheckBox;
import android.widget.CompoundButton;
import android.widget.CompoundButton.OnCheckedChangeListener;
import android.widget.EditText;
import android.widget.Toast;
public class MainActivity extends Activity {
public final static String EXTRA_SALUDO = "com.example.holaamigos.SALUDO";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final EditText txtNombre = (EditText)findViewById(R.id.TxtNombre);
final Button btnHola = (Button)findViewById(R.id.BtnHola);
final CheckBox checkbox1 =(CheckBox)findViewById(R.id.checkBox1);
checkbox1.setOnCheckedChangeListener(new OnCheckedChangeListener(){
#Override
public void onCheckedChanged(CompoundButton arg0,
boolean checked) {
if (checked)
{
Toast.makeText(checkbox1.getContext(), "Activo", Toast.LENGTH_LONG).show();
btnHola.setVisibility(0);
btnHola.setOnClickListener(new OnClickListener() {
#Override
public void onClick(View v) {
Intent intent = new Intent(MainActivity.this, ActivitySaludo.class);
String saludo = txtNombre.getText().toString();
intent.putExtra(EXTRA_SALUDO, saludo);
startActivity(intent);
}
});
}
else
{
Toast.makeText(checkbox1.getContext(), "Inactivo", Toast.LENGTH_SHORT).show();
btnHola.setVisibility(View.INVISIBLE);
}
}
});
}
public void HobbyReturn(int requestcode, int resultadocode, Intent data) {
if (resultadocode == ActivitySaludo.ACEPTAR_OK); {
String string = data.getStringExtra(ActivitySaludo.ACEPTAR_OK);
}
}
#Override
public boolean onCreateOptionsMenu(Menu menu) {
// Inflate the menu; this adds items to the action bar if it is present.
getMenuInflater().inflate(R.menu.main, menu);
return true;
}
}
ActivitySaludo
package com.example.holaamigos;
import com.example.holaamigos.R.string;
import android.app.Activity;
import android.content.Intent;
import android.os.Bundle;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.AdapterView;
import android.widget.AdapterView.OnItemSelectedListener;
import android.widget.ArrayAdapter;
import android.widget.Button;
import android.widget.Spinner;
import android.widget.TextView;
public class ActivitySaludo extends Activity {
public static final String ACEPTAR_OK = "com.example.holaamigos.ACEPTAR_OK";
String myspinner;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_saludo);
Intent intent = getIntent();
String saludo = intent.getStringExtra(MainActivity.EXTRA_SALUDO);
TextView txtCambiado = (TextView) findViewById(R.id.TxtSaludo);
txtCambiado.setText(getString(R.string.hola_saludo) + " " + saludo);
final Spinner spinner = (Spinner)findViewById(R.id.SpinnerSaludo);
ArrayAdapter<CharSequence> adapter = ArrayAdapter.createFromResource(this, R.array.hobby, android.R.layout.simple_spinner_item);
adapter.setDropDownViewResource(android.R.layout.simple_spinner_item);
spinner.setAdapter(adapter);
spinner.setOnItemSelectedListener(new OnItemSelectedListener () {
#Override
public void onItemSelected(AdapterView<?> parent, View view,
int pos, long id) {
parent.getItemAtPosition(pos);
myspinner = spinner.getItemAtPosition(pos).toString();
}
#Override
public void onNothingSelected(AdapterView<?> arg0) {
//another call
}
});
final Button BtnAceptar=(Button) findViewById(R.id.buttonAceptar);
BtnAceptar.setOnClickListener(new OnClickListener (){
#Override
public void onClick(View v) {
Intent iboton = new Intent();
iboton.putExtra("HOBBY", myspinner);
setResult(ACEPTAR_OK, iboton);
finish();
}
});
}
}

You need to start your second activity with the flag that you are waiting for a result, so instead of startActivity you need to make use of startActivityForResult.
If you need a little bit more information take a look at this tutorial it should cover all you need to get things working.