Nsryjdtyk

I have two class : MainActivity and Quake.

package com.example.ex24;



import java.io.IOException;

import java.io.InputStream;

import java.net.HttpURLConnection;

import java.net.URL;

import java.net.URLConnection;

import java.util.ArrayList;



import javax.xml.parsers.DocumentBuilder;

import javax.xml.parsers.DocumentBuilderFactory;

import javax.xml.parsers.ParserConfigurationException;



import org.w3c.dom.Document;

import org.w3c.dom.NodeList;

import org.xml.sax.SAXException;

import org.w3c.dom.Element;



import android.app.ListFragment;

import android.os.Bundle;

import android.os.Handler;

import android.widget.ArrayAdapter;



public class MainActivity extends ListFragment {

ArrayAdapter<Quake> aa ;

ArrayList<Quake> earthquake  = new ArrayList<Quake>();

private Handler handler = new Handler();

@Override

public void onActivityCreated(Bundle savedInstanceState) {

    // TODO Auto-generated method stub

    super.onActivityCreated(savedInstanceState);

    int layoutid = android.R.layout.simple_expandable_list_item_1 ;

    aa = new ArrayAdapter<Quake>(getActivity(), layoutid, earthquake);

    setListAdapter(aa);



    Thread t = new Thread(new Runnable() {



        @Override

        public void run() {

            // TODO Auto-generated method stub

            refreshQ();

        }

    });t.start();

}



public void refreshQ(){

    URL url ;



    try{

    String quakefeed = getString(R.string.quake_feed);

    url = new URL(quakefeed);

    URLConnection connection ;

    connection = url.openConnection();

    HttpURLConnection httpconnection = (HttpURLConnection)connection;

    int responsecode = httpconnection.getResponseCode();



    if(responsecode == HttpURLConnection.HTTP_OK){



        InputStream in = httpconnection.getInputStream();

        DocumentBuilderFactory dbf =DocumentBuilderFactory.newInstance();

        DocumentBuilder db = dbf.newDocumentBuilder() ;



        Document dom = db.parse(in);

        Element docelm = dom.getDocumentElement();

        earthquake.clear();

        NodeList nl = docelm.getElementsByTagName("entry");

        if(nl != null && nl.getLength() > 0 ){



            for(int i = 0 ; i < nl.getLength() ; ++i ){



                Element entry = (Element)nl.item(i);

                Element title =    (Element)entry.getElementsByTagName("title").item(0);



                String title_str =    title.getFirstChild().getNodeValue();

                final Quake quake = new Quake(title_str);

                handler.post(new Runnable() {



                    @Override

                    public void run() {

                        // TODO Auto-generated method stub

                        addNewQ(quake);

                    }

                });

            }



        }









    }





    } catch (SAXException e) {

        // TODO: handle exception

    } catch (IOException e) {

        // TODO Auto-generated catch block

        e.printStackTrace();

    } catch (ParserConfigurationException e) {

        // TODO Auto-generated catch block

        e.printStackTrace();

    }

}



private void addNewQ(Quake _quake){

    earthquake.add(_quake);

    aa.notifyDataSetChanged();

}



}

package com.example.ex24;



public class Quake {



String detalis ;



public String getDetalis(){return detalis ;}



public Quake( String _str ) {

    // TODO Auto-generated constructor stub

    detalis = _str ;

}

@Override

public String toString() {

    // TODO Auto-generated method stub

    return "Detalis :" + detalis ;

}



}

XML

<LinearLayout 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:orientation="vertical"

tools:context=".MainActivity" >



<fragment 

    android:name="com.example.ex24.MainActivity"

    android:id="@+id/EarthquakeListFragment"

    android:layout_width="fill_parent"

    android:layout_height="fill_parent"

    />

<?xml version="1.0" encoding="utf-8"?>

<resources>



<string name="app_name">ex24</string>

<string name="hello_world">Hello world!</string>

<string name="menu_settings">Settings</string>

<string name="quake_feed">http://earthquake.usgs.gov/eqcenter/catalogs/1day-M2.5.xml</string>

now, Why do I get this error?

Unfortunately, ex24 has stopped.

12-24 16:49:02.751: W/Trace(1187): Unexpected value from nativeGetEnabledTags: 0

12-24 16:49:02.751: W/Trace(1187): Unexpected value from nativeGetEnabledTags: 0

12-24 16:49:02.751: W/Trace(1187): Unexpected value from nativeGetEnabledTags: 0

12-24 16:49:02.951: W/Trace(1187): Unexpected value from nativeGetEnabledTags: 0

12-24 16:49:02.951: W/Trace(1187): Unexpected value from nativeGetEnabledTags: 0

12-24 16:49:03.011: D/AndroidRuntime(1187): Shutting down VM

12-24 16:49:03.011: W/dalvikvm(1187): threadid=1: thread exiting with uncaught exception (group=0x40a70930)

12-24 16:49:03.091: E/AndroidRuntime(1187): FATAL EXCEPTION: main

12-24 16:49:03.091: E/AndroidRuntime(1187): java.lang.RuntimeException: Unable to instantiate activity ComponentInfo{com.example.ex24/com.example.ex24.MainActivity}: java.lang.ClassCastException: com.example.ex24.MainActivity cannot be cast to android.app.Activity

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2106)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2230)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.app.ActivityThread.access$600(ActivityThread.java:141)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1234)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.os.Handler.dispatchMessage(Handler.java:99)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.os.Looper.loop(Looper.java:137)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.app.ActivityThread.main(ActivityThread.java:5039)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at java.lang.reflect.Method.invokeNative(Native Method)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at java.lang.reflect.Method.invoke(Method.java:511)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:793)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:560)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at dalvik.system.NativeStart.main(Native Method)

12-24 16:49:03.091: E/AndroidRuntime(1187): Caused by: java.lang.ClassCastException: com.example.ex24.MainActivity cannot be cast to android.app.Activity

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.app.Instrumentation.newActivity(Instrumentation.java:1054)

12-24 16:49:03.091: E/AndroidRuntime(1187):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2097)

12-24 16:49:03.091: E/AndroidRuntime(1187):     ... 11 more

Is this true?

This is My Manifest :

<?xml version="1.0" encoding="utf-8"?>

<manifest xmlns:android="http://schemas.android.com/apk/res/android"

package="com.example.ex24"

android:versionCode="1"

android:versionName="1.0" >



<uses-sdk

    android:minSdkVersion="11"

    android:targetSdkVersion="16" />

<uses-permission android:name="android.permission.INTERNET"/>

<application

    android:allowBackup="true"

    android:icon="@drawable/ic_launcher"

    android:label="@string/app_name"

    android:theme="@style/AppTheme" >

    <activity

        android:name="com.example.ex24.MainActivity"

        android:label="@string/app_name" >

        <intent-filter>

            <action android:name="android.intent.action.MAIN" />



            <category android:name="android.intent.category.LAUNCHER" />

        </intent-filter>

    </activity>

</application>



</manifest>

I guess you have this 'Activity' declared in the manifest as an activity. However, it's a fragment. The system tries to start it, casting it to an Activity in the process, but that is obviously not possible because it's a fragment.

You should change your "class MainActivity extends ListFragment"
into

class MainActivity extends ListActivity

as currently your MainActivity isn't an Activity but a Fragment.

But in your case what you really want is an Activity

You will also get some other errors as Activity has different methods than Fragment

Notes:

Fragment do not need to be in the manifest.