What is wrong in this jsoup code? (Android)

Question

This is the code:

public class MainActivity extends Activity {

private TextView textView2;

private Button button2;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    textView2=(TextView)findViewById(R.id.textView1);
    button2=(Button)findViewById(R.id.button1);
    button2.setOnClickListener(new OnClickListener() {

        @Override
        public void onClick(View v) {
            String url="http://stackoverflow.com/";
                try{
                Document doc=Jsoup.connect(url).get();
                Elements elem=doc.select("meta[name=twitter:domain]");
                        String title1=elem.attr("content");
                        textView2.setText(title1);
            }
            catch(Exception e){

            }
        }
    });
}}

This is the xml code:

<RelativeLayout xmlns:android="http://schemas.android.com/apk/res/android"
xmlns:tools="http://schemas.android.com/tools"
android:layout_width="match_parent"
android:layout_height="match_parent"
android:paddingBottom="@dimen/activity_vertical_margin"
android:paddingLeft="@dimen/activity_horizontal_margin"
android:paddingRight="@dimen/activity_horizontal_margin"
android:paddingTop="@dimen/activity_vertical_margin"
tools:context="com.example.jsouptest.MainActivity" >

<TextView
    android:id="@+id/textView1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentLeft="true"
    android:layout_alignParentTop="true"
    android:layout_marginTop="111dp"
    android:text="TextView"
    android:textSize="100dp" />

<Button
    android:id="@+id/button1"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignLeft="@+id/textView1"
    android:layout_alignParentTop="true"
    android:layout_marginLeft="22dp"
    android:layout_marginTop="34dp"
    android:text="Display" />

It isn't displaying the content in the textview on clicking the button. I have added permission for internet in the manifest file.

Answer 1

You can not call Network on main thread. You must call async task to make network calls. When you click on button execute a async task and then do your stuff there.

Below Code will Help:

public class MainActivity extends Activity {

    TextView textView1;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        textView1 = (TextView) findViewById(R.id.textView1);

        Button b1 = (Button) findViewById(R.id.button1);
        b1.setOnClickListener(new OnClickListener() {

            @Override
            public void onClick(View v) {
                new GetStringTask().execute();
            }
        });
    }

    private class GetStringTask extends AsyncTask<String, Void, String> {

        @Override
        protected String doInBackground(String... params) {
            String url = "http://stackoverflow.com/";
            Document doc = null;
            try {
                doc = Jsoup.connect(url).get();
                Elements elem = doc.getElementsByTag("title");
                String title1 = elem.html();
                return title1;
            } catch (IOException e) {
                e.printStackTrace();
                return "Exception";
            }
        }

        @Override
        protected void onPostExecute(String title) {
            textView1.setText(title);
        }

    }

    @Override
    public boolean onCreateOptionsMenu(Menu menu) {
        getMenuInflater().inflate(R.menu.main, menu);
        return true;
    }

    @Override
    public boolean onOptionsItemSelected(MenuItem item) {
        int id = item.getItemId();
        if (id == R.id.action_settings) {
            return true;
        }
        return super.onOptionsItemSelected(item);
    }
}

the code above sets the TextView label to "Stack Overflow".