简单的jsoup Java HTML解析器将不会更新TextView

Question

I'm attempting to update my textview using web data via JSOUP

http://jsoup.org/

For some reason it never seems to update my TextView with the table data from the URL I'm attempting to gather data from.

Any suggestions?

I've looked over it quite a bit and I cannot seem to spot what I'm doing wrong - but I'm sure it's something simple.

XML:

<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=".MainActivity" >

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
            android:id="@+id/TextView01"
        android:text="@string/hello_world" />

</RelativeLayout>

SOURCE:

public class MainActivity extends Activity {

    TextView tv;
    String url = "http://sheriff.org/apps/arrest/results.cfm?lname=ABBOTT&fname=LAUREA";
    String tr;
    Document doc;

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

        tv = (TextView) findViewById(R.id.TextView01);
        new MyTask().execute(url);
    }

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

        ProgressDialog prog;

        String title = "";

        @Override
        protected void onPreExecute() {
            prog = new ProgressDialog(MainActivity.this);
            prog.setMessage("Loading....");
            prog.show();
        }

        @Override
        protected String doInBackground(String... params) {
            try {
                doc = Jsoup.connect(params[0]).get();
                Element tableElement = doc.select(".datagrid").first();

                Elements tableRows = tableElement.select("tr");
                for (Element row : tableRows) {
                    Elements cells = row.select("td");
                    if (cells.size() > 0) {
                        System.out.println(
                                cells.get(0).text() + "; " + cells.get(1).text() + "; " + cells
                                        .get(2).text() + "; " + cells.get(3).text());
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            return title;
        }


        @Override
        protected void onPostExecute(String result) {
            super.onPostExecute(result);
            prog.dismiss();
            tv.setText(result);
        }
    }
}

EDIT IN RESPONSE TO FIRST ANSWER - STILL NO FIX:

public class MainActivity extends Activity {

    TextView tv;
    String url = "http://sheriff.org/apps/arrest/results.cfm?lname=ABBOTT&fname=LAUREA";
    String tr;
    Document doc;

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

        tv = (TextView) findViewById(R.id.TextView01);
        new MyTask().execute(url);
    }

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

        ProgressDialog prog;

        String title = "";

        @Override
        protected void onPreExecute() {
            prog = new ProgressDialog(MainActivity.this);
            prog.setMessage("Loading....");
            prog.show();
        }

        @Override
        protected String doInBackground(String... params) {
            try {
                doc = Jsoup.connect(params[0]).get();
                Element tableElement = doc.select(".datagrid").first();

                Elements tableRows = tableElement.select("tr");
                for (Element row : tableRows) {
                    Elements cells = row.select("td");
                    if (cells.size() > 0) {
                         title = cells.get(0).text() + "; " + cells.get(1).text() + "; " + 
                                 cells.get(2).text() + "; " + cells.get(3).text();
                    }
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            return title;
        }


        @Override
        protected void onPostExecute(String result) {
            super.onPostExecute(result);
            prog.dismiss();
            tv.setText(result);
        }
    }
}

I also tried:

public class MainActivity extends Activity {

TextView tv;
String url = "http://sheriff.org/apps/arrest/results.cfm?lname=ABBOTT&fname=LAUREA";
String tr;
Document doc;

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

    tv = (TextView) findViewById(R.id.TextView01);
    new MyTask().execute(url);
}

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

    ProgressDialog prog;

    String title = "";

    @Override
    protected void onPreExecute() {
        prog = new ProgressDialog(MainActivity.this);
        prog.setMessage("Loading....");
        prog.show();
    }

    @Override
    protected String doInBackground(String... params) {
        try {
            doc = Jsoup.connect(params[0]).get();
            Element tableElement = doc.select(".datagrid").first();

            Elements tableRows = tableElement.select("tr");
            for (Element row : tableRows) {
                Elements cells = row.select("td");
                if (cells.size() > 0) {
                     title = cells.get(0).text() + "; " + cells.get(1).text() + "; " + 
                             cells.get(2).text() + "; " + cells.get(3).text();
                }
            }
        } catch (IOException e) {
            e.printStackTrace();
        }
        return title;
    }


    @Override
    protected void onPostExecute(String title) {
        super.onPostExecute(title);
        prog.dismiss();
        tv.setText(title);
    }
}
}

Answer 1

1) You don't assign anything to the title variable.

2) Don't use System.out.* . It's for console programs. In Android, use Log

In the doInBackground() change your code to:

 title = cells.get(0).text() + "; " + cells.get(1).text() + "; " + 
 cells.get(2).text() + "; " + cells.get(3).text());