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I'm having problem while scraping data from this website. My code is below:

I want to fecth the data(Marked in the picture)from this URL using Jsoup that I used in my code below.
But I'm having error while doing this. I don't get any value in my String description.
In the MainActivity I declared and intialized the class's object,
description_webscrape dw = new description_webscrape();
dw.execute();
Here's my code of another class.
public class description_webscrape extends AsyncTask<Void,Void,Void>
{
String url = "https://www.ebay.com/sch/i.html?_from=R40&_nkw=shoes&_sacat=0&rt=nc&LH_Sold=1&LH_Complete=1";
description_webscrape(){};
#Override
protected void onPreExecute() {
super.onPreExecute();
}
#Override
protected Void doInBackground(Void... voids) {
org.jsoup.nodes.Document document = null;
try {
document = Jsoup.connect(url).get();
} catch (IOException e) {
e.printStackTrace();
Log.e(TAG, "doInBackground: errorrr---"+e);
}
org.jsoup.select.Elements elements = document.getElementsByClass("srp-controls__count-
heading");
//description is String type and declared globally
description = elements.text();
return null;
}
#Override
protected void onPostExecute(Void unused) {
textView.setText(description+"");
}
}

Why is my code not working in a AsyncTask using the JSoup library for my Android activity?

public class ConnectionTest extends AsyncTask<Void, Void, Void> {
String connection;
String loginFormUrl = "https://intranet.tam.ch/";
#Override
protected Void doInBackground(Void... voids) {
try{
Connection.Response loginForm = Jsoup.connect(loginFormUrl).method(Connection.Method.GET)
.execute();
connection = loginForm.toString();
System.out.print(title);
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
My Activity should just display the connection in a TextView. I have also tried making a Thread and running it in the new Thread but it also won't work.
Here is my Activity
public class Test extends AppCompatActivity {
TextView textView;
ConnectionTest connectionTest = new ConnectionTest();
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
connectionTest.getWebsite();
textView = findViewById(R.id.sdweedew);
textView.setText(connectionTest.connection);
}
}

Change your activity code like this,
I've used a TextView to display the status of the connection.
public class MainActivity extends AppCompatActivity {
private TextView textView;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_test);
textView = findViewById(R.id.sdweedew);
new ConnectionTest().execute();
}
class ConnectionTest extends AsyncTask<Void, Void, String> {
String loginFormUrl = "https://intranet.tam.ch/";
#Override
protected String doInBackground(Void... voids) {
try {
Connection.Response loginForm = Jsoup.connect(loginFormUrl).method(Connection.Method.GET)
.execute();
return loginForm.statusMessage();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onPostExecute(String s) {
if (textView != null) {
textView.setText(s);
}
super.onPostExecute(s);
}
}
}
And remember to add Internet permission in manifest file.
<uses-permission android:name="android.permission.INTERNET" />

please check this code
private void getWebsite() {
new Thread(new Runnable() {
#Override
public void run() {
final StringBuilder builder = new StringBuilder();
try {
Document doc = Jsoup.connect("https://intranet.tam.ch/").get();
String title = doc.title();
Elements links = doc.select("a[href]");
builder.append(title).append("\n");
for (Element link : links) {
builder.append("\n").append("Link : ").append(link.attr("href"))
.append("\n").append("Text : ").append(link.text());
}
} catch (IOException e) {
builder.append("Error : ").append(e.getMessage()).append("\n");
}
runOnUiThread(new Runnable() {
#Override
public void run() {
textView.setText(builder.toString());
}
});
}
}).start();
}

Problem with accessing the views from exception within asyncTask

I am having a problem which is I think that I can't access th,e ListView from the asyncTask
Actually, I really don't know the real problem here
Let me show you what is happening
I have an activity which is executing AsyncTask and creates HttpURLConnection. Sometimes I get an exception (ProtocolException) because the stream un-expectedly ends.
So, I created a handler for this exception that calls a function or a method inside the class of the activity to display a message to the user
Here is a picture so you understand what is my project.
image
the problem here whenever the exception is thrown, the same function/method that I use to add the text to the listView is called, but after it called the listView disappear, but when I minimize the soft keyboard manually the everything becomes fine.
the structure of my class is
public class MainActivity extends AppCompatActivity
{
protected void onCreate(Bundle savedInstanceState)
{
addMessageToListView()//works fin here
}
protected void addMessage(String message, int userMessage, ListView listView) // the function
{
try
{
messages.add(new Message(message,userMessage));
MessagesAdapter messagesAdapter = new MessagesAdapter(messages, getBaseContext());
messagesAdapter.notifyDataSetChanged();
listView.setAdapter(messagesAdapter);
}
catch (Exception exception)
{
}
}
private class HttpPostAsyncTask extends AsyncTask<String, Void, String>
{
...
#Override
protected void onPostExecute(String result)
{
try
{
addMessageToListView()//works fin here
}
catch (Exception exception)
{
}
}
protected String doInBackground(String... params)
{
String result = "";
for (int i = 0; i <= 0; ++i)
{
result = this.invokePost(params[i], this.postData);
}
return result;
}
private String invokePost(String requestURL, HashMap<String, String> postDataParams)// called from doInBackground
{
try
{
addMessageToListView()//works fin here
}
catch (Exception exception)
{
addMessageToListView()//not orking here
}
}
}
}
I don't know how to explain more actually.

You can change Views only in mainthread of your app. The doInBackground doesn't run in mainthread of your app.

Solved by adding:
new Thread()
{
#Override
public void run()
{
MainActivity.this.runOnUiThread(new Runnable()
{
#Override
public void run()
{
addMessageToListView()//not orking here
}
});
super.run();
}
}.start();
Editing the previous code in my question:
public class MainActivity extends AppCompatActivity
{
protected void onCreate(Bundle savedInstanceState)
{
addMessageToListView()//works fin here
}
protected void addMessage(String message, int userMessage, ListView listView) // the function
{
try
{
messages.add(new Message(message,userMessage));
MessagesAdapter messagesAdapter = new MessagesAdapter(messages, getBaseContext());
messagesAdapter.notifyDataSetChanged();
listView.setAdapter(messagesAdapter);
}
catch (Exception exception)
{
}
}
private class HttpPostAsyncTask extends AsyncTask<String, Void, String>
{
...
#Override
protected void onPostExecute(String result)
{
try
{
addMessageToListView()//works fin here
}
catch (Exception exception)
{
}
}
protected String doInBackground(String... params)
{
String result = "";
for (int i = 0; i <= 0; ++i)
{
result = this.invokePost(params[i], this.postData);
}
return result;
}
private String invokePost(String requestURL, HashMap<String, String> postDataParams)// called from doInBackground
{
try
{
addMessageToListView()//works fin here
}
catch (Exception exception)
{
new Thread()
{
#Override
public void run()
{
MainActivity.this.runOnUiThread(new Runnable()
{
#Override
public void run()
{
addMessageToListView()//not orking here
}
});
super.run();
}
}.start();
}
}
}
}

how to return string from AsyncTask to another activity

I have created a class and extend with AsyncTask , now i want to return me a string to another activity throw this class . its getting jsonstring from mysql mDatabase
enter code here
public class GetJson extends AsyncTask<Void,Void,String> {
String JSON_STRING;
String json_url;
public String pasString;
Activity ab;
#Override
protected void onPreExecute() {
json_url="https://XXXXXXX.000webhostapp.com/Json_getData_Survey.php";
}
public GetJson(Activity b) {
ab=b;
}
#Override
protected String doInBackground(Void... params) {
try {
URL url =new URL(json_url);
HttpURLConnection httpURLConnection =(HttpURLConnection) url.openConnection();
InputStream inputStream =httpURLConnection.getInputStream();
BufferedReader bufferedReader=new BufferedReader(new InputStreamReader(inputStream));
StringBuilder stringBuilder=new StringBuilder();
while ((JSON_STRING=bufferedReader.readLine())!=null)
{
stringBuilder.append(JSON_STRING+"\n");
}
bufferedReader.close();
inputStream.close();
httpURLConnection.disconnect();
String strings =stringBuilder.toString().trim();
return strings;
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
#Override
protected void onProgressUpdate(Void... values) {
super.onProgressUpdate(values);
}
#Override
protected void onPostExecute(String result) {
pasString=result;
// Toast.makeText(ab,pasString,Toast.LENGTH_LONG).show();
// json_string1=result;
}
}
i just need to return string1 to my another Activity , i have creaetd a another mehtod in GetJson class to return this string but when i display this it show nothing in it. please help

its Quite simple
make an interface class as following
public interface ResponseListener() {
void onResponseReceive(String data);
}
and add instance of this class in you GetJson class like this
public class GetJson extends AsyncTask<Void,Void,String> {
String JSON_STRING;
String json_url;
public String pasString;
Activity ab;
// this is new code
ResponseListener listener;
public void setOnResponseListener(ResponseListener listener) {
this.listener = listener;
}
#Override
protected void onPreExecute() {
json_url="https://XXXXXXX.000webhostapp.com/Json_getData_Survey.php";
}
// now add this code in onPost function
#Override
protected void onPostExecute(String result) {
pasString=result;
listener.onResponseReceive(pasString);
// Toast.makeText(ab,pasString,Toast.LENGTH_LONG).show();
// json_string1=result;
}
now when you call GetJson from your activity, just simple do that;
GetJson json = new GetJson(Activity.this);
json.setOnResponseListener(new ResponseListener() {
#Override
public void onResponseReceived(String data) {
// here you will get your response
}
});
hope you will understand. :)

Try using activity results. You can set the return value on the one activity, and get it when that activity terminates.
https://developer.android.com/training/basics/intents/result.html

VISIBLE cannot be resolved to a variable

I'm not sure exactly how this can be corrected but I'm getting an error stating: VISIBLE cannot be resolved to a variable. Any suggestions are greatly appreciated. Thus far I've looked over:
http://developer.android.com/reference/android/view/View.html#setVisibility(int)
but I do not understand exactly how this can be implemented in this case.
SOURCE:
public class MainActivity extends Activity {
private TextView textView;
private String response;
public interface Callback {
void onModifiedTextView(String value);
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
textView = (TextView) findViewById(R.id.TextView01);
textView.setVisibility(VISIBLE);
}
public void onModifiedTextView(final String title) {
runOnUiThread(new Runnable() {
public void run() {
textView.setText(title);
textView.invalidate(); // not even necessary
}
});
}
public class DownloadWebPageTask extends AsyncTask<String, Void, String> {
public DownloadWebPageTask(MainActivity mainActivity) {
this.callback = mainActivity;
}
private MainActivity callback;
private String title;
public DownloadWebPageTask() {
// TODO Auto-generated constructor stub
}
public DownloadWebPageTask(TextView textView) {
// TODO Auto-generated constructor stub
}
#Override
protected String doInBackground(String... urls) {
String response = title;
for (String url : urls) {
DefaultHttpClient client = new DefaultHttpClient();
HttpGet httpGet = new HttpGet(url);
try {
Document doc = Jsoup.connect("http://google.com")
.userAgent("Mozilla")
.get();
// get page title
String title = doc.title();
System.out.println("title : " + title);
// get all links
Elements links = doc.select("a[href]");
for (Element link : links) {
// get the value from href attribute
System.out.println("\nlink : " + link.attr("href"));
System.out.println("text : " + link.text());
}
} catch (IOException e) {
e.printStackTrace();
}
}
// callback.onModifiedTextView(response);
return response;
}
#Override
protected void onPostExecute(final String title) {
callback.onModifiedTextView(title);
callback.onModifiedTextView(response);
}
}
public void onClick(View view) {
DownloadWebPageTask task = new DownloadWebPageTask(this);
task.execute(new String[] { "http://www.google.com" });
}
}

VISIBLE is an integer value in the View class. You should change this to View.VISIBLE instead of just VISIBLE, unless you are inside a custom view.

In addtion to #kcoppock answer. You can use
you can use this import:
import static android.view.View.VISIBLE;
or just
textView.setVisibility(View.VISIBLE);
VISIBLE is defined as static final int in the View class.