
AndroidNetworkInfo.java
package com.exercise.AndroidNetworkInfo;
import java.util.ArrayList;
import java.util.List;
import android.app.ListActivity;
import android.content.Context;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Bundle;
import android.widget.ArrayAdapter;
public class AndroidNetworkInfo extends ListActivity {
    /** Called when the activity is first created. */
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        ConnectivityManager connectivityManager 
      = (ConnectivityManager)getSystemService(Context.CONNECTIVITY_SERVICE);
        NetworkInfo[] networkInfo
      = connectivityManager.getAllNetworkInfo();
        
        List<String> listNetworkInfo = new ArrayList<String>();
        for(int i=0; i<networkInfo.length; i++){
         listNetworkInfo.add(networkInfo[i].toString());
        }
        setListAdapter(new ArrayAdapter<String>(this,
          android.R.layout.simple_list_item_1, 
          listNetworkInfo));
        getListView().setTextFilterEnabled(true);
    }
}
Modify AndroidManifest.xml to grant permission to access network state
<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="com.exercise.AndroidNetworkInfo"
      android:versionCode="1"
      android:versionName="1.0">
    <uses-sdk android:minSdkVersion="4" />
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".AndroidNetworkInfo"
                  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>
    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
</manifest>