Ich habe das Problem, dass ich eine NullPointExeption bekomme, wenn ich einen Adapter in meiner ListView setzen möchte. Bevor ich das Fragment mit ListFragment und einem einfachen Adapter erweitert habe, funktioniert das, aber das Problem war, dass ich in dieser Aktivität drei Fragmente mit ListViews habe und Anzeigefehler habe (zeigt die falsche Liste in einem Fragment). Also habe ich beschlossen, für jedes Fragment eigene IDs in der Listenansicht festzulegen, aber jetzt funktioniert es nicht mehr.

Error listview.setAdapter (Adapter):

java.lang.NullPointerException at de.resper.e2cast.MainFragmentLive.onCreateView (MainFragmentLive.java:46)

Fragment

import android.os.Bundle;
import android.util.Log;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ArrayAdapter;
import android.widget.ImageButton;
import android.widget.ListView;

import java.util.ArrayList;
import java.util.List;

import de.resper.e2cast.classes.globalBox;
import de.resper.e2cast.helper.getXml;
import de.resper.e2cast.helper.parseXml;

public class MainFragmentLive extends android.support.v4.app.Fragment {

    private List<String> bouquetListString;
    private ArrayAdapter<String> adapter;
    private globalBox activeBox;
    private ListView listview;

    @Override
    public View onCreateView(LayoutInflater inflater,ViewGroup container, Bundle savedInstanceState) {
        View view = inflater.inflate(R.layout.fragment_main_live, container, false);
        activeBox = ((globalBox) getActivity().getApplicationContext());
        bouquetListString = new ArrayList<String>();
        bouquetListString.add("loading...");
        if(activeBox.isInit()){
            if(activeBox.getBouquets().size() > 0 && activeBox.getBouquets().get(2).size() > 0){
                bouquetListString = activeBox.getBouquets().get(2);
            }else{
                Log.d("Load Bouquet", "XML");
                getBouquetBox();
            }
        }
        listview = (ListView) getActivity().findViewById(R.id.listLive);
        adapter = new ArrayAdapter<String>(getActivity(),android.R.layout.simple_list_item_1, bouquetListString);
        listview.setAdapter(adapter);

        ImageButton reloadBouquet = (ImageButton) view.findViewById(R.id.reloadBouquet);
        reloadBouquet.setOnClickListener(new View.OnClickListener(){
            @Override
            public void onClick(View arg0) {
                getBouquetBox();
            }
        });

        setHasOptionsMenu(true);
        return view;
    }


    public void getBouquetBox(){
        getXml.DownloadCompleteListener dcl = new getXml.DownloadCompleteListener() {
            @Override
            public void onDownloadComplete(String result) {
                bouquetListString.clear();
                String [] tags = {"e2servicereference", "e2servicename"};
                List<List<String>> bouquetsList = parseXml.parseXmlByTag(result, tags);
                activeBox.addBouquets(bouquetsList);
                bouquetListString.addAll(activeBox.getBouquets().get(2));
                adapter.notifyDataSetChanged();
            }
        };
        Log.d("MyLogger", "XML Request GET BOUQUET");
        getXml downloader = new getXml(dcl);
        downloader.execute("http://" + activeBox.getIpPort() + "/web/getservices");
    }
}

Fragment XML:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    android:orientation="vertical"
    android:layout_width="match_parent"
    android:layout_height="match_parent">
    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="horizontal"
        android:layout_margin="8dp">
        <TextView
            android:layout_width="0dip"
            android:layout_height="wrap_content"
            android:layout_weight="0.8"
            android:text="@string/selectBouquet"
            style="@style/header1"/>
        <ImageButton
            android:layout_width="0dip"
            android:layout_height="wrap_content"
            android:id="@+id/reloadBouquet"
            android:src="@drawable/ic_action_refresh"
            android:contentDescription="@string/search"
            android:layout_weight=".20"
            android:layout_gravity="bottom"/>
    </LinearLayout>
    <View
        android:layout_width="fill_parent"
        android:layout_height="1dp"
        android:background="@android:color/darker_gray"/>
    <ListView
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:id="@+id/listLive" />
</LinearLayout>