CODEWITHSUNDEEP
androidtextsettext
user3234077
user3234077

Reputation:

SetText error Android

public class AddNetActivity extends Activity {

String Url = "https://dl.dropboxusercontent.com/u/103170339/WebStock.xml";
TextView textInfo;
ActionBar actionBar;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    actionBar = getActionBar();
    textInfo = (TextView) findViewById(R.id.text_view_new_info);
    // textInfo.setText("adasd"); <<<<<<<<<<<<
    actionBar.setDisplayHomeAsUpEnabled(true);
    NetworkStatusXmlStart();
    setContentView(R.layout.activity_add_net);
}

@Override
public boolean onCreateOptionsMenu(Menu menu) {
    // Inflate the menu; this adds items to the action bar if it is present.
    getMenuInflater().inflate(R.menu.add_net, menu);
    return true;
}

// Respond to Action Buttons
@Override
public boolean onOptionsItemSelected(MenuItem item) {
    // Handle presses on the action bar items
    switch (item.getItemId()) {
        case R.id.action_accept:
            // openAccept();
            return true;
        default:
            return super.onOptionsItemSelected(item);
    }
}

public void NetworkStatusXmlStart(){
    ConnectivityManager connMgr = (ConnectivityManager) 
            getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo networkInfo = connMgr.getActiveNetworkInfo();
        if (networkInfo != null && networkInfo.isConnected()) {
            new WriteToXml().execute(Url);
        } else {
            // show error
        }
}
private class WriteToXml extends AsyncTask<String, Void, String>{
    @Override
    protected String doInBackground(String... urlS){
        try {
            return downloadUrl(urlS[0]);
        } catch (IOException e) {
            return null;
        } catch (XmlPullParserException e) {
            return null;
        }
    }

    @Override
    protected void onPostExecute(String Result){
        // make resutlts
    }
}

private String downloadUrl(String UrlStr) throws XmlPullParserException, IOException{
    InputStream streamInput = null;
    XmlPullParser parser;
    String writed;
    try{
        streamInput = dowStream(UrlStr);
        parser = downloadParser(streamInput);
        writed = WriteToParserAndShow(parser);
    } finally{
        if (streamInput != null) {
            streamInput.close();
        } 
    }
    return writed;
}

private InputStream dowStream(String Surl) throws IOException{
    URL url = new URL (Surl);
    HttpURLConnection conn = (HttpURLConnection) url.openConnection();
    conn.setReadTimeout(10000 /* milliseconds */);
    conn.setConnectTimeout(15000 /* milliseconds */);
    conn.setRequestMethod("GET");
    conn.setDoInput(true);
    // Starts the query
    conn.connect();
    return conn.getInputStream();
}

private XmlPullParser downloadParser(InputStream impStream) throws XmlPullParserException, IOException{
    XmlPullParser parser = Xml.newPullParser();
    parser.setFeature(XmlPullParser.FEATURE_PROCESS_NAMESPACES, false);
    parser.setInput(impStream, null);
    parser.nextTag();
    return parser;
}

private String WriteToParserAndShow(XmlPullParser pars) throws XmlPullParserException, IOException{
    String Info = null, endTagName;


    return Info;
}
}

Why when I want use setText, Activity crushes? When I put it into comment it works fine. Xml file looks like that:

<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=".AddNetActivity"
android:background="#ccccf9" >

<TextView
    android:id="@+id/text_view_new_info"
    android:layout_width="wrap_content"
    android:layout_height="wrap_content"
    android:layout_alignParentTop="true"
    android:layout_centerHorizontal="true"
    android:layout_marginTop="132dp"
    android:text="Large Text"
    android:textAppearance="?android:attr/textAppearanceLarge" />

Tell me if logcat is needed. How change text in this textView? Where is error? Please help

Upvotes: 1

Views: 4751

Answers (4)

TMan
TMan

Reputation: 39

Could you please verify whether your attribute id provided in setText() is correct?. You might have probably encountered a NullPointerException while setText() is being called since the id of the attribute provided in activity_main.xml may not be matching with the attribute_id provided in MainActivity.java

Upvotes: 0

nicooo
nicooo

Reputation: 1

You forgot to inflate your layout. Insert setContentView(R.layout.mylayoutfile) after the super.onCreate() call.

Upvotes: 0

FD_
FD_

Reputation: 12919

You have to call setContentView() before using findViewById().

findViewById iterates over the content view to find the sub view specified by the id you pass as the first argument. But if the content view has not been set yet, how should it find anything?

This leads to a NullPointerException when you access a function or variable of one of the Views that weren't found.

Upvotes: 0

Nambi
Nambi

Reputation: 12042

you are declaring and setting the text in textview before the setContentView

move the setContentView(R.layout.activity_add_net); below the onCreate();

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

Upvotes: 1

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