Develop Reference

NetworkOnMainThreadException while executing Sql query using JDBC driver

i am executing sql query using JDBC driver but it gives me NetworkOnMainThreadException.i have used a Asyntask for the network operation and mention Internet permission in the menifest file. below is my code for executing query
public class getLedger extends AsyncTask<String, Void, Void> {
private ProgressDialog progressDlg;
private ResultSet rs;
#Override
protected void onPreExecute() {
super.onPreExecute();
progressDlg = new ProgressDialog(LedgerActivity.this);
progressDlg.setMessage("Please wait...");
progressDlg.setIndeterminate(false);
progressDlg.setProgressStyle(android.R.style.Widget_ProgressBar_Small);
progressDlg.setCancelable(false);
progressDlg.show();
}
#Override
protected Void doInBackground(String... strings) {
SharedPreferences pref = getSharedPreferences("Login", Context.MODE_PRIVATE);
String ip = pref.getString("ip", "");
String username = pref.getString("username", "");
String password = pref.getString("password", "");
String dbname = pref.getString("dbname", "");
rs = new ExecuteQuery().selectdata(ip, username, password, strings[0], dbname);
return null;
}
#Override
protected void onPostExecute(Void aVoid) {
super.onPostExecute(aVoid);
try {
if (rs != null) {
ArrayList<Ledger> ledgerlist = new ArrayList<>();
while (rs.next()) {
String accode = rs.getString("AC_CODE");
String acname = rs.getString("AC_NAME");
String acaddr = rs.getString("AC_ADD1");
String acmobile = rs.getString("AC_MOBILE");
String actype = rs.getString("AC_TYPE");
String amount = rs.getString("Amount");
String goldwt = rs.getString("GoldWt");
String silverwt = rs.getString("SilverWt");
ledgerlist.add(new Ledger(accode, acname, acaddr, acmobile, actype, amount, goldwt, silverwt));
}
LedgerAdapter adapter = new LedgerAdapter(LedgerActivity.this, ledgerlist);
rcv_ledger.setAdapter(adapter);
}
} catch (SQLException e) {
e.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
}
}

Looks like call to ResultSet.next() uses InputStream under the hood to load row value or something like that.
So to avoid exception you need to return ArrayList<Ledger> from doInBackground() instead of parsing ResultSet in onPostExecute()

Android application crashes if JSON is empty

I am developing an Application of JSON object Which Returns data into ListView.
if json have data then show data in listview..if dont have date then application is crashes.my application is crashes when json is empty.how to resolve this problem..thanx in advancce
here is android code..
public class EmployeePaymentHistory extends Fragment {
HttpParse httpParse = new HttpParse();
ProgressDialog pDialog;
ListView CategoryListView;
ProgressBar progressBar;
List<String> IdList = new ArrayList<>();
private String TAG = EmployeePaymentHistory.class.getSimpleName();
// Http Url For Filter Student Data from Id Sent from previous activity.
String finalResult ;
HashMap<String,String> hashMap = new HashMap<>();
String ParseResult ;
HashMap<String,String> ResultHash = new HashMap<>();
String FinalJSonObject ;
String TempItem;
ProgressDialog progressDialog2;
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
View view = inflater.inflate(R.layout.activity_employee_payment, container, false);
CategoryListView = (ListView)view.findViewById(R.id.listview1);
progressBar = (ProgressBar)view.findViewById(R.id.progressBar);
//Receiving the ListView Clicked item value send by previous activity.
TempItem = getActivity().getIntent().getExtras().getString("ListViewValue1");
//Calling method to filter Student Record and open selected record.
HttpWebCall(TempItem);
// Add Click listener on Delete button.
return view;
}
// Method to Delete Student Record
//Method to show current record Current Selected Record
public void HttpWebCall(final String PreviousListViewClickedItem){
class HttpWebCallFunction extends AsyncTask<String,Void,String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
pDialog = ProgressDialog.show(getActivity(),"Loading Data",null,true,true);
}
#Override
protected void onPostExecute(String httpResponseMsg) {
super.onPostExecute(httpResponseMsg);
pDialog.dismiss();
//Storing Complete JSon Object into String Variable.
FinalJSonObject = httpResponseMsg ;
//Parsing the Stored JSOn String to GetHttpResponse Method.
new EmployeePaymentHistory.GetHttpResponse(getActivity()).execute();
}
#Override
protected String doInBackground(String... params) {
ResultHash.put("CustomerID",params[0]);
ParseResult = httpParse.postRequest(ResultHash, api.EmployeePayment);
return ParseResult;
}
}
HttpWebCallFunction httpWebCallFunction = new HttpWebCallFunction();
httpWebCallFunction.execute(PreviousListViewClickedItem);
}
// Parsing Complete JSON Object.
private class GetHttpResponse extends AsyncTask<Void, Void, Void>
{
public Context context;
List<Customer> CategoryList;
public GetHttpResponse(Context context)
{
this.context = context;
}
#Override
protected void onPreExecute()
{
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... arg0)
{
try
{
if(FinalJSonObject != null)
{
JSONArray jsonArray = null;
try {
jsonArray = new JSONArray(FinalJSonObject);
JSONObject jsonObject;
Customer category;
CategoryList = new ArrayList<Customer>();
for(int i=0; i<jsonArray.length(); i++)
{
category = new Customer();
jsonObject = jsonArray.getJSONObject(i);
category.CustomerName = jsonObject.getString("date").toString();
category.Customertotal = jsonObject.getString("account").toString();
category.CustomerPaid = jsonObject.getString("total").toString();
category.CustomerUnPaid = jsonObject.getString("status").toString();
CategoryList.add(category);
}
}
catch (JSONException e) {
e.printStackTrace();
}
}
else
{
Toast.makeText(context, "abcc", Toast.LENGTH_SHORT).show();
}
}
catch (Exception e)
{
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(Void result)
{
progressBar.setVisibility(View.GONE);
CategoryListView.setVisibility(View.VISIBLE);
CustomerListAdapterClass adapter = new CustomerListAdapterClass(CategoryList, context);
CategoryListView.setAdapter(adapter);
}
}
}
here is php Api code:
<?php
if($_SERVER['REQUEST_METHOD']=='POST'){
include 'DatabaseConfig.php';
$CustomerID= $_POST['CustomerID'];
// Create connection
$conn = new mysqli($HostName, $HostUser, $HostPass, $DatabaseName);
if ($conn->connect_error) {
die("Connection failed: " . $conn->connect_error);
}
$sql = "sELECT b.payerid,a.account as account,b.date as date,b.status as status,b.type as type,sum(b.amount) as total FROM crm_employees a left JOIN sys_transactions b ON a.id = b.payerid where payerid= '$CustomerID' group by b.date ORDER BY a.id desc" ;
$result = $conn->query($sql);
if ($result->num_rows >0) {
while($row[] = $result->fetch_assoc()) {
$tem = $row;
$json = json_encode($tem);
}
} else {
echo "No Results Found.";
}
echo $json;
$conn->close();
}
?>

You need to give the response output same as you are parsing in android side. If you are trying to find a Json object of key name which is not in response then it will crash.
In this scenario you need to handle manually, the values you think it will be null or empty then handle using normal if statements.
Suppose jsonObject.getString("date") object is not fount then using if statements you can handle.
if(jsonObject.getString("date") != null){
//code here
}

I am trying to parse a data from the following link

"http://soccer.sportsopendata.net/v1/leagues/premier-league/seasons/16-17/standings" - Link Which Iam Trying to parse
public class MainActivity extends AppCompatActivity {
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
final Button GetServerData = (Button) findViewById(R.id.GetServerData);
GetServerData.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
// WebServer Request URL
String serverURL = "http://soccer.sportsopendata.net/v1/leagues/premier-league/seasons/16-17/standings";
// Use AsyncTask execute Method To Prevent ANR Problem
new LongOperation().execute(serverURL);
}
});
}
private class LongOperation extends AsyncTask<String, Void, Void> {
private final HttpClient Client = new DefaultHttpClient();
private String Content;
private String Error = null;
private ProgressDialog Dialog = new ProgressDialog(MainActivity.this);
String data = "";
TextView uiUpdate = (TextView) findViewById(R.id.textView2);
TextView jsonParsed = (TextView) findViewById(R.id.textView3);
int sizeData = 0;
EditText serverText = (EditText) findViewById(R.id.textView);
protected void onPreExecute() {
// NOTE: You can call UI Element here.
//Start Progress Dialog (Message)
Dialog.setMessage("Please wait..");
Dialog.show();
try {
// Set Request parameter
data += "&" + URLEncoder.encode("data", "UTF-8") + "=" + serverText.getText();
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
#Override
protected Void doInBackground(String... urls) {
/************ Make Post Call To Web Server ***********/
BufferedReader reader = null;
// Send data
try {
// Defined URL where to send data
URL url = new URL(urls[0]);
// Send POST data request
URLConnection conn = url.openConnection();
conn.setDoOutput(true);
OutputStreamWriter wr = new OutputStreamWriter(conn.getOutputStream());
wr.write(data);
wr.flush();
// Get the server response
reader = new BufferedReader(new InputStreamReader(conn.getInputStream()));
StringBuilder sb = new StringBuilder();
String line = null;
// Read Server Response
while ((line = reader.readLine()) != null) {
// Append server response in string
sb.append(line + "");
}
// Append Server Response To Content String
Content = sb.toString();
} catch (Exception e) {
Error = e.getMessage();
} finally {
try {
reader.close();
} catch (Exception ex) {
}
}
return null;
}
protected void onPostExecute(Void unused) {
// NOTE: You can call UI Element here.
// Close progress dialog
Dialog.dismiss();
if (Error != null) {
uiUpdate.setText("Output : " + Error);
}else
{
//Show Response Json Onscreen(Activity)
uiUpdate.setText( Content );
/****************** Start Parse Response JSON Data *************/
String OutputData = "";
try {
JSONObject jsono = new JSONObject(Content);
JSONObject mainObject = jsono.getJSONObject("data");
JSONArray jsonArray = mainObject.getJSONArray("standing");
for (int i = 0; i < jsonArray.length(); i++) {
JSONObject object = jsonArray.getJSONObject(i);
// get details2 JSONObject
String position = object.optString("position").toString();
String team = object.optString("team").toString();
OutputData += "Position: " + position + " "
+ "Team Name : " + team + " ";
}
/****************** End Parse Response JSON Data *************/
//Show Parsed Output on screen (activity)
jsonParsed.setText( OutputData );
}catch (JSONException e) {
e.printStackTrace();
}
}
}
}
}
**I am Creating a premier league application which shows all the datas needed for a premier league fan. As Iam new to this I am getting confused over json parsing and getting data from apis. So Can anyone Explain to me how to change my code or Some links which would help me correct it.
Above given is my java code of Main Activity.**

Thank You Everyone for Helping out. But I found my answer from the search over the internet. Here I used VOLLEY to call the link.
JSON PARSER CLASS
public class ParseJSON {
public static String[] position1;
public static String[] team;
public static String[] points;
public static final String JSON_ARRAY = "data";
public static final String CHILD_ARRAY = "standings";
public static final String KEY_ID = "position";
public static final String KEY_NAME = "team";
private JSONObject users = null;
private JSONArray user2=null;
private JSONObject user3=null;
private String json;
public ParseJSON(String json){
this.json = json;
}
protected void parseJSON() {
JSONObject jsonObject = null;
try {
jsonObject = new JSONObject(json);
users = jsonObject.getJSONObject(JSON_ARRAY);
try {
user2=users.getJSONArray(CHILD_ARRAY);
position1 = new String[user2.length()];
team = new String[user2.length()];
points=new String[user2.length()];
for (int i = 0; i < user2.length(); i++) {
JSONObject jo = user2.getJSONObject(i);
try {
user3=jo.getJSONObject("overall");
points[i] = user3.getString("points");
System.out.println("Message me: "+points[i]);
}catch (Exception e)
{
e.printStackTrace();
}
position1[i] = jo.getString(KEY_ID);
team[i] = jo.getString(KEY_NAME);
System.out.println("Message me: "+position1[i]);
System.out.println("Message me: "+team[i]);
}
}catch (Exception e)
{
e.printStackTrace();
}
} catch (JSONException e) {
e.printStackTrace();
}
}
}
Main Activity Class
public class MainActivity extends AppCompatActivity implements View.OnClickListener {
public static final String JSON_URL="http://soccer.sportsopendata.net/v1/leagues/premier-league/seasons/16-17/standings";
private Button buttonGet;
private ListView listView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
buttonGet = (Button) findViewById(R.id.buttonGet);
buttonGet.setOnClickListener(this);
listView = (ListView) findViewById(R.id.listView);
}
#Override
public void onClick(View v) {
sendRequest();
}
private void sendRequest() {
final StringRequest stringRequest = new StringRequest(JSON_URL,
new Response.Listener<String>() {
#Override
public void onResponse(String response) {
showJSON(response);
}
},
new Response.ErrorListener() {
#Override
public void onErrorResponse(VolleyError error) {
Toast.makeText(MainActivity.this, error.getMessage(), Toast.LENGTH_LONG).show();
}
});
RequestQueue requestQueue = Volley.newRequestQueue(this);
requestQueue.add(stringRequest);
}
private void showJSON(String json){
ParseJSON pj = new ParseJSON(json);
pj.parseJSON();
CustomList cl = new CustomList(this, ParseJSON.position1,ParseJSON.team,ParseJSON.points);
listView.setAdapter(cl);
}
}
Custom Class for adding datas to list view
public class CustomList extends ArrayAdapter<String> {
private String[] position1;
private String[] team;
private String[] points;
private Activity context;
public CustomList(Activity context, String[] position1, String[] team, String[] points) {
super(context, R.layout.list_view_layout, position1);
this.context = context;
this.position1 = position1;
this.team = team;
this.points = points;
}
#Override
public View getView(int position, View convertView, ViewGroup parent) {
LayoutInflater inflater = context.getLayoutInflater();
View listViewItem = inflater.inflate(R.layout.list_view_layout, null, true);
TextView pos1 = (TextView) listViewItem.findViewById(R.id.position1);
TextView teamname = (TextView) listViewItem.findViewById(R.id.teamname);
TextView points1 = (TextView) listViewItem.findViewById(R.id.points);
pos1.setText("Position: "+position1[position]);
teamname.setText("Team: "+team[position]);
points1.setText("Points: "+points[position]);
return listViewItem;
}
}

Step 1 : Use Retroft + RxJava for Asynchronous API calls
Step 2 : Use Gson to Serialize and Deserialize.
Step 3 : Use json to POJO to have a Model Class
Simplify the code.

JSON returns data in one code and null in other

I have an app that connects to server sends sql request and get JSON answer as JsonArray.
Its Asynktask in seperate class (HTTPRequest.java is my AsyncTask class, Responce.java its my callback interface class) and it works correct.
when I use it in OrderActivity.java like below
#Override //my interface class function
public void onPostExecute(JSONArray Result) {
load(Result);
}
private void load(JSONArray json) {
for(int i=0;i<json.length();i++){
try {
JSONObject jo = json.getJSONObject(i);
Product p = new Product(
jo.getInt("ID"),
jo.getInt("parent"),
jo.getInt("category"),
jo.getString("Item"),
jo.getDouble("Price")
);
products.add(p);
} catch (JSONException e) {
e.printStackTrace();
}
}
it does work and fills product with data, but when I assign to my class variable JSONArray json
JSONArray json = new JSONArray;
.
.
.
#Override
public void onPostExecute(JSONArray Result) {
json = Result;
}
json is null
//HTTPRequest.java
public class HTTPRequest extends AsyncTask<String, Void, Integer> {
private Context context;
private Responce responce;
JSONArray json;
public HTTPRequest(Context context){
this.context = context;
responce = (Responce)context;
}
#Override
protected Integer doInBackground(String... params) {
OutputStream output;
InputStream inputStream = null;
HttpURLConnection connection = null;
String charset = "UTF-8";
Integer result = 0;
try {
URL uri = new URL(params[0]);
connection = (HttpURLConnection) uri.openConnection();
connection.setDoOutput(true);
connection.setRequestProperty("Accept-Charset", charset);
connection.setRequestProperty("Content-Type", "text/plain; charset=" + charset);
output = connection.getOutputStream();
output.write(params[1].getBytes(charset));
output.close();
int statusCode = connection.getResponseCode();
if (statusCode == 200) {
inputStream = new BufferedInputStream(connection.getInputStream());
json = new JSONArray(getJSON(inputStream));
result = 1;
}
} catch (Exception e) {
e.getLocalizedMessage();
}
return result;
}
#Override
protected void onPostExecute(Integer i) {
super.onPostExecute(i);
if(i == 1) {
responce.onPostExecute(json);
} else {
responce.onPostExecute(null);
}
}
private String getJSON(InputStream inputStream) throws IOException, JSONException {
StringBuffer stringBuffer = new StringBuffer();
BufferedReader bufferedReader = new BufferedReader( new InputStreamReader(inputStream));
String line = "";
String result = null;
while((line = bufferedReader.readLine()) != null) {
stringBuffer.append(line.toString());
}
result = stringBuffer.toString();
if(null!=inputStream){
inputStream.close();
}
return result;
}
}
//Responce.java
public interface Responce {
public void onPostExecute(JSONArray Result);
}
//OrderActivity.java
public class OrderActivity extends Activity implements Responce{
ArrayList<Product> products = new ArrayList<Product>();
ProductAdapter productAdapter;
OrderItemAdapter orderItemAdapter;
ListView orderlist;
JSONArray ja;
Button btnBack;
Button btnTakeOrder;
ListView picklist;
HTTPRequest httpRequest;
String url = "http://192.168.3.125:8888/data/";
String query = "select * from vwitems order by category desc";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_order);
StrictMode.ThreadPolicy policy = new StrictMode.ThreadPolicy.Builder().permitAll().build();
StrictMode.setThreadPolicy(policy);
orderlist =(ListView)findViewById(R.id.orderlist);
orderItemAdapter = new OrderItemAdapter(OrderActivity.this);
btnBack = (Button)findViewById(R.id.btnBack);
btnBack.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
productAdapter.filter(0);
}
});
btnTakeOrder = (Button)findViewById(R.id.btnTakeOrder);
btnTakeOrder.setOnClickListener(new View.OnClickListener() {
#Override
public void onClick(View v) {
Integer oid = 0;
Order order = new Order(OrderActivity.this);
oid = order.NewOrder(1, 2, 3);
Toast.makeText(OrderActivity.this," " + order.getCount(), LENGTH_SHORT).show();
}
});
orderlist.setAdapter(orderItemAdapter);
picklist = (ListView) findViewById(R.id.picklist);
picklist.setOnItemClickListener(new AdapterView.OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view, int position, long id) {
int pid = 0;
if (productAdapter.getItem(position).isCategory()) {
pid = productAdapter.getItem(position).getId();
productAdapter.filter(pid);
} else {
OrderItem oi = new OrderItem();
oi.setItemId(productAdapter.getItem(position).getId());
oi.setItem(productAdapter.getItem(position).getItem());
oi.setPrice(productAdapter.getItem(position).getPrice());
search(oi);
}
}
});
httpRequest = new HTTPRequest(this);
httpRequest.execute(url, query);
}
private boolean search(OrderItem oi){
int size = orderItemAdapter.getCount();
int i = 0;
if(size != 0)
for(OrderItem o : orderItemAdapter.getAll()){
if(o.getItemId() == oi.getItemId()){
orderItemAdapter.getItem(i).setQuantity(orderItemAdapter.getItem(i).getQuantity() + 1);
orderItemAdapter.notifyDataSetChanged();
return true;
}
i++;
}
orderItemAdapter.addItem(oi);
orderItemAdapter.notifyDataSetChanged();
return false;
}
private void load(JSONArray json) {
for(int i=0;i<json.length();i++){
try {
JSONObject jo = json.getJSONObject(i);
Product p = new Product(
jo.getInt("ID"),
jo.getInt("parent"),
jo.getInt("category"),
jo.getString("Item"),
jo.getDouble("Price")
);
products.add(p);
} catch (JSONException e) {
e.printStackTrace();
}
}
productAdapter = new ProductAdapter(OrderActivity.this, products);
picklist.setAdapter(productAdapter);
productAdapter.filter(0);
}
#Override
public void onPostExecute(JSONArray Result) {
load(Result);
}
/*
#Override
public void onPostExecute(JSONArray Result) {
json = Result;
}
**/
}
sorry i forgot include this one
//Order.java
public class Order implements Responce{
private Context context;
private JSONArray json = new JSONArray();
private HTTPRequest httpRequest;
private int OrderID;
private Date OrderDate;
private int OrderTable;
private int Waiter;
private byte OrderStatus;
private List<OrderItem> orderItems;
public Order(Context context){
this.context = context;
}
//some code here...
public Integer NewOrder(Integer guests, Integer waiter, Integer ordertable){
String query = "insert into orders(orderdate, guests, waiter, ordertable) VALUES(NOW()," + guests + ", " + waiter + ", " + ordertable + "); SELECT LAST_INSERT_ID() as ID;";
Integer result = 0;
Connect(query);
try {
JSONObject jo = json.getJSONObject(0);
result = jo.getInt("ID");
} catch (JSONException e) {
e.printStackTrace();
}
return result; //here i got 0 if i init result to 0, null or what ever i init my
}
#Override
public void onPostExecute(JSONArray Result) {
json = Result;
}
private void Connect (String query){
httpRequest = new HTTPRequest(context);
httpRequest.execute("http://192.168.3.125:8888/data/", query);
}
}

Multiple Async Tasks one after another Android

I'm trying to fetch data from server in saving in SQLite database through Async task on Splash. i have multiple tables on server and need to fetch one after another. I'm trying this way
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.splash);
StrictMode.setThreadPolicy(new StrictMode.ThreadPolicy.Builder().detectDiskReads().detectDiskWrites().detectNetwork()
.penaltyLog().build());
url = getResources().getString(R.string.url);
db = new SQLCont(context);
new asyn_Task1(Splash.this).execute();
}
public class asyn_Task1 extends AsyncTask<String, Void, Boolean> {
public asyn_Task1(Splash activiy) {
context = activiy;
}
#Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
new asyn_Task2(Splash.this).execute();
}
#Override
protected void onPreExecute() {
super.onPreExecute();
progressdialog = new ProgressDialog(Splash.this);
progressdialog.setTitle("Processing....");
progressdialog.setMessage("Please Wait.....1 /10");
progressdialog.setCancelable(false);
progressdialog.show();
}
#Override
protected Boolean doInBackground(String... params) {
postParameters.add(new BasicNameValuePair("001", data));
try {
CustomHttpClient.executeHttpGet("001");
} catch (Exception e1) {
e1.printStackTrace();
}
String response = null;
// call executeHttpPost method passing necessary parameters
try {
response = CustomHttpClient.executeHttpPost(
url,
postParameters);
// store the result returned by PHP script that runs
// MySQL query
String result = response.toString();
// parse json data
try {
JSONArray jArray = new JSONArray(result);
for (int i = 0; i < jArray.length(); i++) {
JSONObject json_data = jArray.getJSONObject(i);
id = json_data.getString("id");
st_name = " " + json_data.getString("name");
st_contact = json_data.getString("contact");
st_category = json_data.getString("Category");
st_address = json_data.getString("address");
Log.d("favourite_data", "" + id + st_name + st_contact
+ st_category + st_address);
db.adddata_hospital(context, st_name,st_contact,
st_category, st_address);
}
} catch (JSONException e) {
Log.e("log_tag", "Error parsing data " + e.toString());
}
} catch (Exception e) {
Log.e("log_tag", "Error in http connection!!" + e.toString());
}
return null;
}
}
public class asyn_Task2 extends AsyncTask<String, Void, Boolean> {
public asyn_Task2(Splash activiy) {
context = activiy;
}
#Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
new asyn_Task3(Splash.this).execute();
}
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Boolean doInBackground(String... params) {
// some stuff here
}
return null;
}
}
public class asyn_Task3 extends AsyncTask<String, Void, Boolean> {
public asyn_blood_Group(Splash activiy) {
context = activiy;
}
#Override
protected void onPostExecute(Boolean result) {
super.onPostExecute(result);
progressdialog.dismiss();
}
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Boolean doInBackground(String... params) {
// some stuff here
}
return null;
}
}
problem is that data is added for asyn_Task1 it repeated every time
expected out put
abc def ghi
jkl mno pqr
mno pqr stu
But getting output
abc def ghi
abc def ghi
abc def ghi

You will get your data based on your query. If you always execute same query then you will always get same data.
And from my point of view if possible single AsyncTask for that purpose. when all the query is completed then onpostExecute() callback will fired.