android - 空指针列表适配器android

Question

我创建了自己的适配器来将一些音乐会放在列表中。没有日期分隔符，一切正常，但是有了它们，当您向下滚动列表并为将出现在屏幕上的每个新行调用 convertView 函数时，我在 convertView 函数的以下行中得到 NullPointer 异常：

tvNombre.setText(entry.getArtista());

但是我可以在日志中打印艺术家的名字，并且我修改了将正确的列表传递给适配器。有谁能够帮我？

提前致谢。

    listConciertoEvento.add(new ConciertoEvento("dia_0", "", new GregorianCalendar(2012,10,dia,0,0)));

    listConciertoEvento.add(new ConciertoEvento(x++,"Moodyman","Becool","Electrónica",
            new GregorianCalendar(2012,10,dia,23,30),new GregorianCalendar(2012,10,dia+1,5,0),"","",10));
    listConciertoEvento.add(new ConciertoEvento(x++,"Chinese Man","Razzmataz 2","Trip-Hop",
            new GregorianCalendar(2012,10,dia,21,0),new GregorianCalendar(2012,10,dia,23,0),"","", 50));
    listConciertoEvento.add(new ConciertoEvento(x++,"Kreator","Razzmataz","Thrash Metal",
            new GregorianCalendar(2012,10,dia,20,30),new GregorianCalendar(2012,10,dia,23,0),"","",10));
    listConciertoEvento.add(new ConciertoEvento(x++,"Barricada","KGB","Rock",
            new GregorianCalendar(2012,10,dia,22,0),new GregorianCalendar(2012,10,dia+1,0,30),"","", 50));
    listConciertoEvento.add(new ConciertoEvento(x++,"The Buzzcocks","Apolo","Thrash Metal",
            new GregorianCalendar(2012,10,dia,21,30),new GregorianCalendar(2012,10,dia,23,30),"","",10));
    listConciertoEvento.add(new ConciertoEvento(x++,"Mr.Oizo","La 2","Electrónica",
            new GregorianCalendar(2012,10,dia,23,30),new GregorianCalendar(2012,10,dia+1,3,0),"","", 50));



    dia++;
    //listConciertoEvento.add(new ConciertoEvento("dia_1", "", new GregorianCalendar(2012,10,dia,0,0)));

        listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_1","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_2","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_3","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_4","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_5","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_6","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_7","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_8","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_9","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_10","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_11","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_12","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_13","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_14","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));
    listConciertoEvento.add(new ConciertoEvento(x++,"Cannibal Corpse_15","Razzmataz","Death Metal",new GregorianCalendar(2012,10,13,13,30),new GregorianCalendar(2012,10,13,15,0),"","", 15));

这里是适配器上 convertView 的代码：

    public View getView(int position, View convertView, ViewGroup viewGroup) {

    ConciertoEvento entry = listConciertoEvento.get(position);
    if (convertView == null) {

        if (!entry.getArtista().startsWith("dia_")){

            Log.v("lalalala", "XXXX layout concierto");

            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.concierto_evento_row, null);

        }else{

            Log.v("lalalala", "XXXX layout dia");

            LayoutInflater inflater = (LayoutInflater) context.getSystemService(Context.LAYOUT_INFLATER_SERVICE);
            convertView = inflater.inflate(R.layout.dia_row, null);
        }
    }

final int id = entry.getId();
    if (!entry.getArtista().startsWith("dia_")){

        Log.v("lalalala", "XXXX is concert");

        ImageView imSquare = (ImageView) convertView.findViewById(R.id.imSquare);

        TextView tvNombre = (TextView) convertView.findViewById(R.id.tvNombre);

        Log.v("lalalala", entry.getArtista());
        tvNombre.setText(entry.getArtista());
        Log.v("lalalala", "XXXX tvNombre.setText(entry.getArtista()); done");


        TextView tvPath = (TextView) convertView.findViewById(R.id.tvPath);
        tvPath.setText(entry.getPath_imagen());



    }else{
        Log.v("lalalala", "XXXX is day");
        Log.v("lalalala", entry.getArtista());

    }

    return convertView;
}

这里的日志：

10-22 12:23:11.468: V/lalalala(582): XXXXXXXXXXX  xivato en fragment2
10-22 12:23:11.468: V/lalalala(582): dia_0
10-22 12:23:11.468: V/lalalala(582): Kreator
10-22 12:23:11.468: V/lalalala(582): Chinese Man
10-22 12:23:11.468: V/lalalala(582): The Buzzcocks
10-22 12:23:11.468: V/lalalala(582): Barricada
10-22 12:23:11.468: V/lalalala(582): Mr.Oizo
10-22 12:23:11.468: V/lalalala(582): Moodyman
10-22 12:23:11.468: V/lalalala(582): dia_1
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_15
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_14
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_13
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_12
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_11
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_10
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_9
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_8
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_7
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_6
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_5
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_4
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_3
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_2
10-22 12:23:11.468: V/lalalala(582): Cannibal Corpse_1
10-22 12:23:11.619: D/dalvikvm(582): GC_EXTERNAL_ALLOC freed 130K, 51% free 2642K/5379K, external 904K/1038K, paused 48ms
10-22 12:23:11.669: V/lalalala(582): XXXX layout dia
10-22 12:23:11.669: V/lalalala(582): XXXX is day
10-22 12:23:11.669: V/lalalala(582): dia_0
10-22 12:23:11.679: V/lalalala(582): XXXX layout concierto
10-22 12:23:11.739: D/dalvikvm(582): GC_EXTERNAL_ALLOC freed 12K, 51% free 2640K/5379K, external 1058K/1570K, paused 50ms
10-22 12:23:11.779: V/lalalala(582): XXXX is concert
10-22 12:23:11.779: V/lalalala(582): Kreator
10-22 12:23:11.779: V/lalalala(582): XXXX tvNombre.setText(entry.getArtista()); done
10-22 12:23:11.789: V/lalalala(582): XXXX layout concierto
10-22 12:23:11.799: V/lalalala(582): XXXX is concert
10-22 12:23:11.799: V/lalalala(582): Chinese Man
10-22 12:23:11.799: V/lalalala(582): XXXX tvNombre.setText(entry.getArtista()); done
10-22 12:23:11.809: V/lalalala(582): XXXX layout concierto
10-22 12:23:11.819: V/lalalala(582): XXXX is concert
10-22 12:23:11.819: V/lalalala(582): The Buzzcocks
10-22 12:23:11.819: V/lalalala(582): XXXX tvNombre.setText(entry.getArtista()); done
10-22 12:23:11.819: V/lalalala(582): XXXX layout concierto
10-22 12:23:11.839: V/lalalala(582): XXXX is concert
10-22 12:23:11.839: V/lalalala(582): Barricada
10-22 12:23:11.839: V/lalalala(582): XXXX tvNombre.setText(entry.getArtista()); done
10-22 12:23:11.839: V/lalalala(582): XXXX layout concierto
10-22 12:23:11.869: V/lalalala(582): XXXX is concert
10-22 12:23:11.879: V/lalalala(582): Mr.Oizo
10-22 12:23:11.879: V/lalalala(582): XXXX tvNombre.setText(entry.getArtista()); done
10-22 12:23:11.889: V/lalalala(582): XXXX layout concierto
10-22 12:23:11.899: V/lalalala(582): XXXX is concert
10-22 12:23:11.899: V/lalalala(582): Moodyman
10-22 12:23:11.899: V/lalalala(582): XXXX tvNombre.setText(entry.getArtista()); done
10-22 12:23:11.909: V/lalalala(582): XXXX layout dia
10-22 12:23:11.909: V/lalalala(582): XXXX is day
10-22 12:23:11.909: V/lalalala(582): dia_1
10-22 12:23:11.909: V/lalalala(582): XXXX layout concierto
10-22 12:23:11.929: V/lalalala(582): XXXX is concert
10-22 12:23:11.929: V/lalalala(582): Cannibal Corpse_15
10-22 12:23:11.929: V/lalalala(582): XXXX tvNombre.setText(entry.getArtista()); done
10-22 12:23:37.829: W/KeyCharacterMap(582): No keyboard for id 0
10-22 12:23:37.829: W/KeyCharacterMap(582): Using default keymap: /system/usr/keychars/qwerty.kcm.bin
10-22 12:23:39.729: V/lalalala(582): XXXX is concert
10-22 12:23:39.739: V/lalalala(582): Cannibal Corpse_14
10-22 12:23:39.739: D/AndroidRuntime(582): Shutting down VM
10-22 12:23:39.749: W/dalvikvm(582): threadid=1: thread exiting with uncaught exception (group=0x40015560)
10-22 12:23:39.769: E/AndroidRuntime(582): FATAL EXCEPTION: main
10-22 12:23:39.769: E/AndroidRuntime(582): java.lang.NullPointerException
10-22 12:23:39.769: E/AndroidRuntime(582):  at com.u.totsound.AdapterConciertoEvento.getView(AdapterConciertoEvento.java:89)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.AbsListView.obtainView(AbsListView.java:1409)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.ListView.addViewBelow(ListView.java:2914)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.ListView.scrollListItemsBy(ListView.java:2843)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.ListView.arrowScrollImpl(ListView.java:2340)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.ListView.arrowScroll(ListView.java:2287)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.ListView.commonKey(ListView.java:2089)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.ListView.onKeyDown(ListView.java:2036)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.KeyEvent.dispatch(KeyEvent.java:1256)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.View.dispatchKeyEvent(View.java:3855)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:787)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.ListView.dispatchKeyEvent(ListView.java:2021)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.widget.TabHost.dispatchKeyEvent(TabHost.java:278)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewGroup.dispatchKeyEvent(ViewGroup.java:789)
10-22 12:23:39.769: E/AndroidRuntime(582):  at com.android.internal.policy.impl.PhoneWindow$DecorView.superDispatchKeyEvent(PhoneWindow.java:1687)
10-22 12:23:39.769: E/AndroidRuntime(582):  at com.android.internal.policy.impl.PhoneWindow.superDispatchKeyEvent(PhoneWindow.java:1120)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.app.Activity.dispatchKeyEvent(Activity.java:2073)
10-22 12:23:39.769: E/AndroidRuntime(582):  at com.android.internal.policy.impl.PhoneWindow$DecorView.dispatchKeyEvent(PhoneWindow.java:1663)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewRoot.deliverKeyEventToViewHierarchy(ViewRoot.java:2560)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewRoot.handleFinishedEvent(ViewRoot.java:2535)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.view.ViewRoot.handleMessage(ViewRoot.java:1867)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.os.Handler.dispatchMessage(Handler.java:99)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.os.Looper.loop(Looper.java:123)
10-22 12:23:39.769: E/AndroidRuntime(582):  at android.app.ActivityThread.main(ActivityThread.java:3683)
10-22 12:23:39.769: E/AndroidRuntime(582):  at java.lang.reflect.Method.invokeNative(Native Method)
10-22 12:23:39.769: E/AndroidRuntime(582):  at java.lang.reflect.Method.invoke(Method.java:507)
10-22 12:23:39.769: E/AndroidRuntime(582):  at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:839)
10-22 12:23:39.769: E/AndroidRuntime(582):  at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:597)
10-22 12:23:39.769: E/AndroidRuntime(582):  at dalvik.system.NativeStart.main(Native Method)

score 1 · Accepted Answer

are you aware that ListAdapter has its way to manage different kind of row?

You should rely on public int getItemViewType (int position) and public int getViewTypeCount () instead of check if the entry.getArtist() starts with "dia". The issue is surely related to this.

android - 空指针列表适配器android

1 回答 1

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