Develop Reference

How to fix AsyncTask params error?

I am working on a registration based project that uses asyncTask. But I am getting errors on its params and the background usage tasks.
Snippet -
public class signupActivity extends AppCompatActivity {
EditText edit_name;
EditText edit_usn;
EditText edit_addnum;
EditText edit_pass;
EditText edit_repass;
Button btn_sign;
private static final String REGISTER_URL="http://abcd.000webhostapp.com/signup.php";
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_signup);
edit_name=(EditText)findViewById(R.id.id_name);
edit_usn=(EditText)findViewById(R.id.id_usn);
edit_addnum=(EditText)findViewById(R.id.id_add);
edit_pass=(EditText)findViewById(R.id.id_pass);
edit_repass=(EditText)findViewById(R.id.id_repass);
btn_sign=(Button)findViewById(R.id.btn_signup);
btn_sign.setOnClickListener(new View.OnClickListener(){
#Override
public void onClick(View v) {
registerUser();
}
});
}
private void registerUser() {
String name=edit_name.getText().toString().trim().toLowerCase();
String usn=edit_usn.getText().toString().trim().toLowerCase();
String addnum=edit_addnum.getText().toString();
String pass=edit_pass.getText().toString().trim().toLowerCase();
String repass=edit_repass.getText().toString().trim().toLowerCase();
register(name, usn, addnum, pass, repass);
}
private void register(String name,String usn,String addnum,String pass,String repass) {
String urlsuffix = "?name=" + name + "&usn=" + usn + "&ddnum=" + addnum + "&pass=" + pass + "&repass=" + repass;
//Getting **illegal start of type** for void keyword here
class RegisterUser extends AsyncTask <String, void, String> implements abcd.project2.RegisterUser {
ProgressDialog loading;
#Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(signupActivity.this, "please wait", null, true, true);
}
//Getting **method does not override or implement a method from a supertype** for override here
#Override
protected void onPostExecute() {
super.onPreExecute();
Toast.makeText(getApplicationContext(), "Internet not found", Toast.LENGTH_SHORT).show();
}
#Override
protected String doInBackground(String... params) {
String s = params[0];
BufferedReader bufferReader = null;
try {
URL url = new URL(REGISTER_URL + s);
HttpURLConnection con = (HttpURLConnection) url.openConnection();
bufferReader = new BufferedReader(new InputStreamReader(con.getInputStream()));
String result;
result = bufferReader.readLine();
return result;
} catch (Exception e) {
return null;
}
}
}
RegisterUser ur = new RegisterUser();
ur.execute(urlsuffix);
}
public void openCreateList(View view) {
Intent i = new Intent(this, createActivity.class);
startActivity(i);
}}
Error messages -
Error:(56, 50) error: illegal start of type Error:(65, 9) error:
method does not override or implement a method from a supertype
How do I solve these?
I tried changing the return type in params but still I am unable to solve the error.

Try this
Its Void not void in parameter of AsyncTask
You need to change your onPostExecute() method just pass String parameter in onPostExecute() method
Change your code like below code
SAMPLE CODE
private void register(String name,String usn,String addnum,String pass,String repass) {
String urlsuffix = "?name=" + name + "&usn=" + usn + "&ddnum=" + addnum + "&pass=" + pass + "&repass=" + repass;
//Getting **illegal start of type** for void keyword here
class RegisterUser extends AsyncTask<String, Void, String> implements abcd.project2.RegisterUser {
ProgressDialog loading;
#Override
protected void onPreExecute() {
super.onPreExecute();
loading = ProgressDialog.show(signupActivity.this, "please wait", null, true, true);
}
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
}
#Override
protected String doInBackground(String... params) {
String s = params[0];
BufferedReader bufferReader = null;
try {
URL url = new URL(REGISTER_URL + s);
HttpURLConnection con = (HttpURLConnection) url.openConnection();
bufferReader = new BufferedReader(new InputStreamReader(con.getInputStream()));
String result;
result = bufferReader.readLine();
return result;
} catch (Exception e) {
return null;
}
}
}
RegisterUser ur = new RegisterUser();
ur.execute(urlsuffix);
}
You can read more about AsyncTask

change word "void" to Void in the line of class RegisterUser extends AsyncTask <String, void, String> implements abcd.project2.RegisterUser
The three types used by an asynchronous task are the following:
Params, the type of the parameters sent to the task upon execution.
Progress, the type of the progress units published during the background computation.
Result, the type of the result of the background computation.
Not all types are always used by an asynchronous task. To mark a type as unused, simply use the type Void:
private class MyTask extends AsyncTask { ... }
refer this Official document site :

1.Change void to Void
2.change your onPostExecute()
#Override
protected void onPostExecute(String s) {
super.onPostExecute(s);
Toast.makeText(getApplicationContext(), "Internet not found", Toast.LENGTH_SHORT).show();
}

AsyncTask not working inside ViewPager

I am having problem with AsyncTask class inside ViewPager's Fragment.
I have added code like below inside ViewPager's 3rd Fragment:
private View.OnClickListener finishClickListener = new View.OnClickListener() {
#Override
public void onClick(View v) {
UserIdAsyncTask userIdAsyncTask = new UserIdAsyncTask( getActivity(), "URL", "Test", "Value" );
userIdAsyncTask.execute();
Her is my UserIdAsyncTask class:
private class UserIdAsyncTask extends AsyncTask<Void, Void, String> {
String url = "";
String oldpass = "";
String newpass = "";
private Context mContext = null;
private ProgressDialog dialog;
public UserIdAsyncTask( Context context, String url, String oldPass, String newPass ) {
this.mContext = context;
this.url = url;
this.oldpass = oldPass;
this.newpass = newPass;
}
#Override
protected void onPreExecute() {
dialog = ProgressDialog.show(this.mContext, "", "Please wait...");
dialog.setCanceledOnTouchOutside(false);
dialog.show();
}
#Override
protected String doInBackground(Void... params) {
String str = "";
try {
return str;
} catch (Exception e) {
Log.e(ThirdFrag.class.toString(), e.getMessage(), e);
}
return str;
}
#Override
protected void onPostExecute(String response) {
dialog.dismiss();
Intent i = new Intent(getActivity(), ABC.class);
startActivity(i);
getActivity().finish();
}
}
In the given code, onPreExecute() called but doInBackground() never called.
Any ideas anyone? I'm really struggling with this one.

Android AsyncTask Dialog fast close

My code:
private class selectBookInAutor extends AsyncTask<String, Void, String> {
#Override
protected void onPreExecute() {
super.onPreExecute();
arr_book_title.clear();
arr_book_href.clear();
mProgressDialog = new ProgressDialog(_context);
mProgressDialog.setMessage("Loading...");
mProgressDialog.setIndeterminate(false);
mProgressDialog.show();
}
#Override
protected String doInBackground(String... params) {
Document doc = null;
StringBuilder sb = new StringBuilder();
try {
doc = Jsoup.connect(params[0]).userAgent("Mozilla").get();
Elements links = doc.select("li>a");
for (Element link : links) {
sb.append(link.text());
arr_book_title.add(link.text());
arr_book_href.add(Jsoup.clean(link.attr("abs:href"), Whitelist.basic()));
}
} catch (IOException e) {
e.printStackTrace();
}
return sb.toString();
}
#Override
protected void onPostExecute(String result) {
if (result != ""){
final CharSequence[] items = arr_book_title.toArray(new CharSequence[arr_book_title.size()]);
final ArrayList seletedItems = new ArrayList();
AlertDialog.Builder builder = new AlertDialog.Builder(_context);
builder.setTitle("Select The Difficulty Level");
builder.setMultiChoiceItems(items, null, new DialogInterface.OnMultiChoiceClickListener() {
#Override
public void onClick(DialogInterface dialog, int indexSelected, boolean isChecked) {
if (isChecked) {
seletedItems.add(indexSelected);
}else if(seletedItems.contains(indexSelected)){
seletedItems.remove(Integer.valueOf(indexSelected));
}
}
}).setPositiveButton(R.string.button_ok, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int id) {
for (Object s : seletedItems){
String[] separated = selGroupParam.split(";");
String _idautor = separated[0].toString();
long id_book = db.insertBOOK(_idautor, arr_book_href.get(Integer.valueOf(s.toString())).toString(), "", arr_book_title.get(Integer.valueOf(s.toString())).toString());
new **saveBookInAutor().execute(arr_book_href.get(Integer.valueOf(s.toString())).toString(), _idautor, String.valueOf(id_book));**
}
refreshList();
}
}).setNegativeButton(R.string.button_cancel, new DialogInterface.OnClickListener() {
#Override
public void onClick(DialogInterface dialog, int id) {
}
}).create().show();
}else{
Toast.makeText(_context, "Error", Toast.LENGTH_SHORT).show();
}
mProgressDialog.dismiss();
}
}
private class saveBookInAutor extends AsyncTask<String, Void, String> {
String _idautor, _idbook;
#Override
protected void onPreExecute() {
super.onPreExecute();
mProgressDialog2 = new ProgressDialog(_context);
mProgressDialog2.setMessage("Save to file");
mProgressDialog2.setIndeterminate(false);
mProgressDialog2.show();
}
#Override
protected String doInBackground(String... params) {
Document doc = null;
String _html = "";
_idautor = params[1];
_idbook = params[2];
try {
doc = Jsoup.connect(params[0]).userAgent("Mozilla").get();
_html = doc.select("dd").outerHtml();
} catch (IOException e) {
e.printStackTrace();
}
return Jsoup.clean(_html, Whitelist.basic());
}
#Override
protected void onPostExecute(String result) {
if (result != ""){
Toast.makeText(_context, "Save file", Toast.LENGTH_SHORT).show();
String html = "<html lang='ru'><head><meta http-equiv='Content-Type' content='text/html; charset=UTF-8'/></head><body>"+result+"</body></html>";
//String html = result;
**savePageToFile(_idautor + "_" + String.valueOf(_idbook), html);**
}else{
Toast.makeText(_context, "Error", Toast.LENGTH_SHORT).show();
}
mProgressDialog2.dismiss();
}
}
public void refreshList() {
Intent intent = new Intent(_context, MainActivity.class);
intent.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP);
_context.startActivity(intent);
}
public void savePageToFile(String filename, String html) {
try {
OutputStreamWriter outputStreamWriter = new OutputStreamWriter(_context.openFileOutput(filename, Context.MODE_PRIVATE));
outputStreamWriter.write(html);
outputStreamWriter.close();
}
catch (IOException e) {
//Log.e("Exception", "File write failed: " + e.toString());
}
}
When you select a page and clicking "Ok" ProgressDialog mProgressDialog2 opens and displays just a 1 second. Because of this, I do not see the download Page or not.
How to make mProgressDialog2 displayed all the while to save the page as a file?
Thank you!
UPD
What i want is :
Start mProgressDialog.
After downloading the page disappears and AlertDialog comes with the question what to choose.
After choosing, mProgressDialog2 should be displayed as long as it downloads and saves the file in the webpage.
However mProgressDialog2 disappears in 1 second, and process of saving the file goes on in silence.

In your onPostExecute method, you unconditionally call
mProgressDialog2.dismiss();
This is closing the dialog immediately after it is displayed. That call should be moved to the handler code for each of the buttons. (i.e.the onClick method for the positive and negative buttons)

in onPostExecute(), compare Strings like
if(!result.equals(""))
and try once.
use equals() method for String comparisons.

ProgressDialog Android

I am trying to use ProgressDialog. when i run my app the Progress Dialog box show and disappear after 1 second. I want to show it on completion of my process.. Here is my code:
public class MainActivity extends Activity {
android.view.View.OnClickListener mSearchListenerListener;
private ProgressDialog dialog;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
new YourCustomAsyncTask().execute(new String[] {null, null});
}
private class YourCustomAsyncTask extends AsyncTask <String, Void, Void> {
protected void onPreExecute() {
dialog = new ProgressDialog(MainActivity.this);
dialog.setMessage("Loading....");
dialog.setIndeterminate(true);
dialog.setCancelable(true);
dialog.show(); //Maybe you should call it in ruinOnUIThread in doInBackGround as suggested from a previous answer
}
protected void doInBackground(String strings) {
try {
// search(strings[0], string[1]);
runOnUiThread(new Runnable() {
public void run() {
// updateMapWithResult(); //Or call it onPostExecute before progressDialog's dismiss. I believe this method updates the UI so it should run on UI thread
}
});
} catch(Exception e) {
}
}
#Override
protected void onPostExecute(Void params) {
dialog.dismiss();
//result
}
#Override
protected Void doInBackground(String... params) {
// TODO Auto-generated method stub
return null;
}
}
}
Updated Question:
#Override
public void onCreate(SQLiteDatabase db) {
mDatabase = db;
Log.i("PATH",""+mDatabase.getPath());
mDatabase.execSQL(FTS_TABLE_CREATE);
loadDictionary();
}
/**
* Starts a thread to load the database table with words
*/
private void loadDictionary() {
new Thread(new Runnable() {
public void run() {
try {
loadWords();
} catch (IOException e) {
throw new RuntimeException(e);
}
}
}).start();
}
private void loadWords() throws IOException {
Log.d(TAG, "Loading words...");
for(int i=0;i<=25;i++)
{ //***//
final Resources resources = mHelperContext.getResources();
InputStream inputStream = resources.openRawResource(raw_textFiles[i]);
//InputStream inputStream = resources.openRawResource(R.raw.definitions);
BufferedReader reader = new BufferedReader(new InputStreamReader(inputStream));
try {
StringBuilder sb = new StringBuilder();
while ((word = reader.readLine()) != null)
{
sb.append(word);
// Log.i("WORD in Parser", ""+word);
}
String contents = sb.toString();
StringTokenizer st = new StringTokenizer(contents, "||");
while (st.hasMoreElements()) {
String row = st.nextElement().toString();
String title = row.substring(0, row.indexOf("$$$"));
String desc = row.substring(row.indexOf("$$$") + 3);
// Log.i("Strings in Database",""+title+""+desc);
long id = addWord(title,desc);
if (id < 0) {
Log.e(TAG, "unable to add word: " + title);
}
}
} finally {
reader.close();
}
}
Log.d(TAG, "DONE loading words.");
}
I want to show ProgressDialogue box untill all words are not entered in the database. This code is in inner calss which extends SQLITEHELPER. so how to can i use ProgressDialogue in that inner class and run my addWords() method in background.

You cannot have this
runOnUiThread(new Runnable() {
public void run() {
// updateMapWithResult(); //Or call it onPostExecute before progressDialog's dismiss. I believe this method updates the UI so it should run on UI thread
}
});
in your doInBackground().
Progress dialog doesn't take priority when there is some other action being performed on the main UI thread. They are intended only when the actions are done in the background. runonUIthread inside doInBackground will not help you. And this is normal behavior for the progressdialog to be visible only for few seconds.

You have two doInBackground() methods inside your AsyncTask Class. Remove the runOnUiThread() from First doInBackground() and move it to second doInBackground() which has #Override annotation.
I don't know whether you wantedly written two doInBackground() methods or by mistake but it is not good to have such confusion between the Method. Your AsyncTask is not calling the first doInBackground() and it will call doInBackground() which has #Override annotation. So your ProgressDialog is dismissed in 1 second of time as it returns null immediately.

Progress Dialog only shows up when the job is already done

I have a problem which I don't understand. I want to show a simple Progress Dialog in Android. So I created an AsyncTask and create the dialog in the constructor. I use the methods onPreExceution to initialise the dialog and the onPostExecute method I destory the dialog. So until now this looks total correct for me. But when I start the App on my Nexus 7 the dialog doesn't show up till the job is done. So it shows up for a half of a second at the end of the job... What am I doing wrong?
Thank you for your help ;)
public class ParseHTMLCodeNew extends AsyncTask<String, Void, String> {
ProgressDialog dialog;
public ParseHTMLCodeNew(Context context) {
dialog = new ProgressDialog(context);
}
#Override
protected void onPreExecute() {
//einrichten des Wartedialogs
dialog.setTitle("Bitte warten!");
dialog.setMessage("Die Kommentare werden vom Server geladen.");
dialog.show();
}
#Override
protected String doInBackground(String params) {
InputStream is = null;
String data = "";
try
{
URL url = new URL( params[0] );
is = url.openStream();
data = new Scanner(is).useDelimiter("//html//").next();
}
catch ( Exception e ) {
e.printStackTrace();
}
return data;
}
#Override
protected void onPostExecute(String result) {
//Dialog beenden RSS Feed ist fertig geparst
if (dialog != null && dialog.isShowing()) {
dialog.dismiss();
}
}
}
UPDATE
This is my new AsyncTask:
public class ParseHTMLCodeNew extends AsyncTask<String, String, String> {
ProgressDialog dialog;
private final OnCompleteTaskListener onCompleteTaskListener;
public interface OnCompleteTaskListener {
void onComplete(String data);
}
public ParseHTMLCodeNew(Context context, OnCompleteTaskListener taskListener) {
onCompleteTaskListener = taskListener;
dialog = new ProgressDialog(context);
}
#Override
protected void onPreExecute() {
//einrichten des Wartedialogs
dialog.setTitle("Bitte warten!");
dialog.setMessage("Die Kommentare werden vom Server geladen.");
dialog.show();
}
#Override
protected String doInBackground(String... params) {
InputStream is = null;
String data = "";
try
{
URL url = new URL( params[0] );
is = url.openStream();
data = new Scanner(is).useDelimiter("//html//").next();
}
catch ( Exception e ) {
e.printStackTrace();
}
return data;
}
#Override
protected void onPostExecute(String result){
onCompleteTaskListener.onComplete(result);
//Dialog beenden RSS Feed ist fertig geparst
if (dialog != null && dialog.isShowing()) {
dialog.dismiss();
}
}
}
And i am calling it this way:
new ParseHTMLCodeNew(this,new OnCompleteTaskListener() {
#Override
public void onComplete(String data) {
gData = data;
}
}).execute(url);
As i commented on your post, data has no value.

If you calling this code so:
String data = new ParseHTMLCodeNew(CommentActivity.this).execute(url).get();
Then you do not really see your dialogue because there is a blocking UI.
Method get() waits if necessary for the computation to complete, and then retrieves its result.
Call so:
new ParseHTMLCodeNew(CommentActivity.this).execute(url);
and the result of the work is handled directly in the AsyncTask.
If you need to transfer the data to the main thread, you should tell him that the task was completed.
Wat is the simple code, I just added OnCompleteTaskListener interface
public class ParseHTMLCodeNew extends AsyncTask<String, Void, String> {
private final OnCompleteTaskListener onCompleteTaskListener;
private ProgressDialog dialog;
public interface OnCompleteTaskListener {
void onComplete(String data);
}
public ParseHTMLCodeNew(Context context, OnCompleteTaskListener taskListener) {
onCompleteTaskListener = taskListener;
dialog = new ProgressDialog(context);
}
#Override
protected void onPreExecute() {
// einrichten des Wartedialogs
dialog.setTitle("Bitte warten!");
dialog.setMessage("Die Kommentare werden vom Server geladen.");
dialog.show();
}
#Override
protected String doInBackground(String... params) {
StringBuilder sb = new StringBuilder();
// your code here
try {
for (int i = 0; i < 100; i++) {
Thread.sleep(100);
sb.append(i);
}
} catch (InterruptedException e) {
e.printStackTrace();
}
return sb.toString();
}
#Override
protected void onPostExecute(String result) {
// Dialog beenden RSS Feed ist fertig geparst
if (dialog != null && dialog.isShowing()) {
dialog.dismiss();
}
onCompleteTaskListener.onComplete(result);
}
}
And the example of a call
new ParseHTMLCodeNew(this,new OnCompleteTaskListener() {
#Override
public void onComplete(String data) {
Toast.makeText(CommentActivity.this, data, Toast.LENGTH_LONG).show();
}
}).execute("your_url");
Be careful, this code can produce errors when you rotate your Phone.
When Activity destroyed but task is performed:
- progress dialog will close and will not open again
- local variable to dialog or context is incorrect.
If the operation is performed for a long time can make it through the of the services?

I've wrote a code that get data from online database and populate that data in lisview here is the part of my code hope that help !
class LoadMyData extends AsyncTask<String, String, String> {
//Before starting background thread Show Progress Dialog
protected void onPreExecute() {
super.onPreExecute();
pDialog = new ProgressDialog(getParent());
pDialog.setMessage("Loading. Please wait...");
pDialog.setIndeterminate(false);
pDialog.setCancelable(false);
pDialog.show();
}
protected String doInBackground(String... args) {
//Your code here
return null;
}
/**
* After completing background task Dismiss the progress dialog
* **/
protected void onPostExecute(String file_url) {
// dismiss the dialog after getting the data
pDialog.dismiss();
// updating UI from Background Thread
runOnUiThread(new Runnable() {
public void run() {
// In my case use my adapter to display the data in a listview
adapter = new MyAdaper();
list.setAdapter(adapter);
}
});
}
}

Progress dialog should be shown from UI thread
runOnUiThread(new Runnable() {
public void run() {
dialog.setTitle("Bitte warten!");
dialog.setMessage("Die Kommentare werden vom Server geladen.");
dialog.show();
}});